Episode #387: The Valsalva Maneuver- Blood Pressure & Safety in Lifting

0:01 [SPEAKER_01]: In 1704, an Italian anatomist named Antonio Maria Valsava, published a paper called The Treatise on the Human Year. [SPEAKER_01]: In this paper, he wasn't looking for a way to squat 500 pounds. [SPEAKER_01]: He wasn't interested in core stability. [SPEAKER_01]: Instead, he was looking at gross, infected, middle ear pus.

0:16 [SPEAKER_01]: He told his patients to plug their noses, close their mouths, and blow as hard as they could. [SPEAKER_01]: The goal literally squeeze the infection out through a perforated ear drum. [SPEAKER_01]: And so, for the next 150 years, the most famous maneuver in lifting history was just a dirty ear trick.

0:31 [SPEAKER_01]: But then, the 1850s happened. [SPEAKER_01]: Two German physiologists, the Weber Brothers, decided to see what happened if you kept blowing. [SPEAKER_01]: They did it to themselves until they induced Bratocardia, low heart rate, and they fainted. [SPEAKER_01]: Suddenly, the ear trick became the Weber experiment.

0:46 [SPEAKER_01]: It was no longer a way to clear an infection, it was a way to stop your heart. [SPEAKER_01]: By the 1960s, the medical literature was filled with reports of sudden death and ventricular arrest associated with the strain. [SPEAKER_01]: In 1985, a study by McDougall changed everything. [SPEAKER_01]: He used catheters inside arteries of people who were maxing out on the leg press, and he recorded blood pressures up to 480 over 350mm of mercury.

1:09 [SPEAKER_01]: A to cardiologist, that's a crime scene waiting to happen. [SPEAKER_01]: and the origin of the boogie man. [SPEAKER_01]: It's why your doctor, your trainer, and every safety first influencer tells you that you shouldn't hold your breath when you lift. [SPEAKER_01]: Assuming that the human body is a fragile tube waiting to pop.

1:22 [SPEAKER_01]: But what if they're wrong? [SPEAKER_01]: Today, we're taking apart decades of Valsalva phobia and not just in lifters on the platform, but also in pregnant women and people with the history of heart disease. [SPEAKER_01]: And help me cut through the BS, it's the second most handsome doctor in North America.

1:37 [SPEAKER_01]: A man who never lets the pressure get to him, mostly because he knows exactly how to brace for it. [SPEAKER_01]: He's also the subject of the most famous Valsava meme to date. [SPEAKER_01]: Dr. Austin Baraki, what's going on man? [SPEAKER_00]: Man, what an honor. [SPEAKER_00]: It's been some time, I think, since I've seen that meme making the rounds, but it certainly still is out there and still from time to time, people send me versions, and I believe I received it in a handful of different languages and across various contexts of business and crypto, and I don't know how much other things it's been ported into, but yeah.

2:10 [SPEAKER_01]: Yeah, you know, if, [SPEAKER_01]: There's a Mr. Worldwide, are you, are you Dr. Worldwide? [SPEAKER_00]: When I come to the polls, maybe I'll end up in a card deck of what do you mean one day? [SPEAKER_00]: Honestly, that would be awesome. [SPEAKER_01]: That would be amazing. [SPEAKER_01]: Yes.

2:25 [SPEAKER_01]: Yeah, the real, the real, the real blow up. [SPEAKER_01]: All right. [SPEAKER_01]: Well, we're talking about the Valsalva maneuver, and so I guess this is a good time as any, is to define what is the Valsalva maneuver. [SPEAKER_01]: So this sounds kind of like a high end Italian soup or some sort of a pulsarmic vinaigrette, but if you're listening to this and you aren't currently driving or operating heavy machinery, actually even if you are, you've probably already done one today without thinking about it.

2:50 [SPEAKER_01]: Perhaps this morning after a cup of coffee, if you catch my drift, [SPEAKER_01]: But to do this, I want you to take a breath in, not a maximal lungs are about to burst type of breath, just a normal breath. [SPEAKER_01]: Now, close your throat, keep your mouth shut, and try to exhale. [SPEAKER_01]: Heart, you feel that immediate tightening of your gut in your abdomen that's pressure, building in your chest, and maybe little thumping in your ears.

3:14 [SPEAKER_01]: Congratulations, you've just successfully performed of Al-Savam Nover. [SPEAKER_01]: You closed your glottis, you contracted your expireatory muscles, and you've turned your torso into a pressurized [SPEAKER_01]: Now, if you're a doctor, you're probably taught that what you just did is a good way to get rid of an regular heartbeat.

3:30 [SPEAKER_01]: And if you're a lifter, you call it bracing. [SPEAKER_01]: But to the man who actually gave this thing a name, Antonio Maria Valsava, it was just a way to deal with some really gross ears. [SPEAKER_01]: I said, I don't know if you actually are familiar with the history of the Valsava maneuver.

3:45 [SPEAKER_00]: I don't, my main experience is either in the lifting context or yet to terminate certain forms of rapid heart rhythms. [SPEAKER_01]: Yeah, well, so it was named after an Italian anatomist in Surgeon from the 1700s, Antonio Maria Valsalva, actually wrote a paper called the Treatis on Human Ear.

4:03 [SPEAKER_01]: And it wasn't for squats, it was for middle-ear insulation, plugging the nose to blow out stuff inside your ears in this case, plus from a perforated ear drum, and in a twist of irony, he described them maneuver for ears and never mentioned its effects on the harder cardiovascular system, yet he eventually died of a stroke.

4:21 [SPEAKER_01]: Medicine, do you be like that sometimes? [SPEAKER_01]: So at that point, this was just like a trick to get rid of against some pests in the middle of the year. [SPEAKER_01]: And that was in the 1700s, but the history is pretty interesting, as far as how maybe some Valsalva phobia developed.

4:36 [SPEAKER_01]: So you fast forward about 150 years to 1850, and these two German physiologists Edward and Ernst Weber, [SPEAKER_01]: First, link this maneuver to the heart. [SPEAKER_01]: They performed it until they induced Bray to Cardio, which is a slow heart rate, and then they fainted, passed out.

4:52 [SPEAKER_01]: Technically, instead of it calling the Balsal maneuver, you could have called it the Weber maneuver, perhaps. [SPEAKER_01]: Uh, so that's 1850s go forward another 100 years now in the 1960s and 70s, a few case reports started popping up about sudden death and ventricular arrest with the Valsava maneuver.

5:10 [SPEAKER_01]: Uh, these were again case reports, not like, you know, large studies, but then things changed in the 80s. [SPEAKER_01]: 1985, there's this famous McDougall study. [SPEAKER_01]: Uh, [SPEAKER_01]: This research group put intra-artarial cathars, so basically pressure sensors inside the arteries of people lifting weights They're doing leg press near maximal weights and the average blood pressure that was directly monitored was 320 over 250 Now just to you know, give you an anchor normal blood pressure resting blood pressure is usually less than 120 over 80 So they were 320 over 250 with a one individual achieving a blood pressure of 480 over 350 [SPEAKER_01]: Uh, I don't know if this was the origin story, the villain arc for this Valsava phobia in modern medicine, but it certainly could be.

5:56 [SPEAKER_01]: I mean, if you're a doctor in the mid 80s, you see a study like this coming up that bullet blood pressure effectively looks like a typo, uh, like our hypertensive emergency and any other setting. [SPEAKER_01]: It makes total sense to me why some in the medical community kind of panicked.

6:10 [SPEAKER_01]: They thought, uh, oh, look at that 480 over 350. [SPEAKER_01]: But Austin, when we look at the anatomy of a Valsauva maneuver, it's not just one big spike, there's sort of a sequence of events here. [SPEAKER_01]: Can you walk us through the four phases of the Valsauva maneuver because how long you hold that breath seems to make a difference?

6:26 [SPEAKER_00]: Yeah, it's super interesting, especially for physiology nerds like myself, and it is illustrative of a handful of different really important concepts between pressure and volume, [SPEAKER_00]: neurological and cardiovascular reflex arcs that try to maintain certain parameters in like a reasonable range, whatever, whatever reasonable ends up being, but really like to support life essentially.

6:52 [SPEAKER_00]: So the first phase when you close that glottis or close off your throat and you're trying to exhale against it, that's when the muscles that facilitate exhalation are contracting, squeezing down around your ribcage, and essentially raising the pressure inside your [SPEAKER_00]: But this has two different implications.

7:15 [SPEAKER_00]: The first of that increased in intraturacic pressure is essentially forcing blood out of your of the vessels that are in your thorax, while also preventing blood from the rest of your body from being able to effectively return to your thorax and eventually your heart. [SPEAKER_00]: And so that's the initial phase when there's an immediate transience increase in blood pressure as that blood is forced out.

7:38 [SPEAKER_00]: And then because the blood pressure has rapidly gone up, some of that homeostasis comes into play, and your heart rate reflexively goes down. [SPEAKER_00]: And because cardiac output relates to the balance, so to speak, between your heart is beating, and then how much blood is being pumped out per beat.

7:57 [SPEAKER_00]: The next phase as you kind of sustain your breath hold has some more interesting sorts of consequences. [SPEAKER_00]: As I mentioned, when the pressure in your thorax is really high, that prevents blood from returning to your heart from the rest of your body. [SPEAKER_00]: This is why, for example, if you watch somebody from the moment they hold their breath at the start of a Valsalva and you watch the veins in their neck, they will gradually become more and more engaged at that is like a traffic jam.

8:23 [SPEAKER_00]: As blood is building up in those veins, trying to make its way back down to your heart, but there's a blockage in that blockage is essentially that really high pressure. [SPEAKER_00]: And so suddenly, because there's not enough blood coming back to the heart, well, the heart doesn't have what it needs to pump out new blood to the rest of your body.

8:40 [SPEAKER_00]: And so with that, some more sustained Valsalva, that sustained breath hold preventing the heart from refilling and pumping out fresh blood. [SPEAKER_00]: Your blood pressure gradually starts to decrease. [SPEAKER_00]: as the blood pressure gradually decreases, your heart rate now goes in the other direction to compensate.

8:56 [SPEAKER_00]: It has to pick back up to try to maintain your blood pressure because you don't have the volume of blood, so you have to pump faster to try to get a similar enough amount of blood out to keep things flowing and to keep blood going to your brain and to keep you conscious. [SPEAKER_00]: The next phase, if you were to release the breath hold or kind of allow air to come into your lungs, then suddenly all of that increase in introtheresic pressure has dissipated.

9:21 [SPEAKER_00]: Now, you have low introtheresic pressure because that's how we actually take air in is by lowering the pressure in our chest, so we physically suck air into our lungs. [SPEAKER_00]: There's a few kind of instantaneous changes that happen in that situation. [SPEAKER_00]: Suddenly, we're not squeezing blood out of our chest anymore, and also the blood vessels in our lungs are able to expand.

9:45 [SPEAKER_00]: So there's this kind of momentary pooling of blood in the lungs and kind of more on the right side of the heart with not quite as much yet filling the left side of the heart that's ready to pump it out to the body. [SPEAKER_00]: And so when you're in that in between state, not pumping a ton of blood out to the body just yet because it hasn't had time to equilibrate, you might have a little bit of that dizziness that's seeing stars.

10:06 [SPEAKER_00]: The blood pressure is not making its way up to your brain and you might have a brown out or even borderline approach losing consciousness potentially. [SPEAKER_00]: So this is actually when we see a fair amount of those types of passing out episodes is later. [SPEAKER_00]: So if you've seen a lot of these like lifting videos have [SPEAKER_00]: So it made their way around the internet where somebody actually often will complete the lift and it's then after they set the weight down, for example, a re-rack the weight and then it's a couple seconds later after they have released their breath hold and things are trying to re-equilibrate that you start to see, it's like they have that, you know, glazed over a look in their eyes and maybe they start to have to brace themselves or they might actually collapse.

10:41 [SPEAKER_00]: And then the last period is when recovery happens and this can be a period where there's actually some overshooting of the kind of the response physiology here. [SPEAKER_00]: So the blood now that was previously kind of backed up in the venous system is rushing back to fill to fill the heart both sides.

10:59 [SPEAKER_00]: But our heart had been compensating for that low blood volume by beating away at a faster heart rate. [SPEAKER_00]: And so now we have to kind of re-address re-equilibrate. [SPEAKER_00]: return to homeostasis because now we have all this blood coming back that's ready to get pumped out and our heart rate is still high And so that's when blood pressure actually goes back up again because we have a lot of volume and a fast heart rate that's pumping So sometimes people in myself, I know I've experienced this in this phase [SPEAKER_00]: Where you start to hear your heartbeat in your ears, that like wishing noise and things like that until it gradually kind of settles back down all of that is because of these hemodynamic changes that are happening during recovery until your neurological reflex arcs and cardiovascular reflex arcs kind of resettle back into the to their normal state.

11:43 [SPEAKER_00]: So, really interesting physiology that has to try to keep you conscious and equilibrated and maintain blood pressure because blood pressure is life and a lot of it comes down to understanding what is the impact of pressure in your thorax on forcing blood out of your heart preventing blood from coming back to your heart and then what's the reverse sequence of that once you actually are allowing those pressure changes to reverse.

12:04 [SPEAKER_01]: Yeah, there's a great explanation, and I think one take away from that, despite all of the interesting quirks and features of the Balsalv maneuver is that all of this stuff is reflexive. [SPEAKER_01]: You're not consciously raising your heart rate, you know, lower-insert pressures that here or there, and you like that.

12:24 [SPEAKER_01]: It's all reflexive, which actually kind of leads into the next section perfectly. [SPEAKER_01]: we do on a regular basis, perform Valsalvemenover's reflexively, all the time. [SPEAKER_01]: And in addition, you can do them intentionally, but I think it's important to discuss when we do these things reflexively, because that bears some importance when we discuss the idea of not doing of Valsalvemenover when you lift.

12:47 [SPEAKER_01]: So, some real world examples of this reflexive or involuntary ball-solva, every time you cough, or you sneeze, these generate transient pressure spikes often higher than a sub-maximal squat, you're doing a ball-solva maneuver. [SPEAKER_01]: If you've ever tried to catch something falling off the counter, particularly if it's heavy, anytime you've gone to the bathroom, number two in particular, [SPEAKER_01]: You're doing a Valsalva maneuver, uh, reflexively.

13:12 [SPEAKER_01]: You don't, again, usually have to think about it for most folks. [SPEAKER_01]: Basically, when the body needs to produce and transmit muscular force efficiently, it wants to make your midsection rigid. [SPEAKER_01]: And to do so, it increases the pressure inside your abdomen and your chest, which we call intra-abdominal and intra-therasic pressure, respectively.

13:30 [SPEAKER_01]: So there's a long mechanism here that I talked about on our podcast about belts, but Austin already described this when he was discussing the physiology, which I called the anatomy of the Valsov maneuver in Ointour, our preferences, but I want to put some numbers on the pressure actually inside your abdomen.

13:49 [SPEAKER_01]: So he focused on the intro thoracic pressure like in your chest, but underneath the diaphragm, you have your abdomen and you've got organs inside there and that pressure bubble gets kind of transmitted to the abdomen and then you have muscles all around there which you can also contract to increase that pressure and also the rigidity of the segment.

14:08 [SPEAKER_01]: Now, if you're just baseline, standing up right, not doing of all solvent over the pressure inside your abdomen is about 20 millimeters of mercury. [SPEAKER_01]: Now, if you're standing and you're doing a Valsava, it's about 65 millimeters of mercury. [SPEAKER_01]: If you were to jump, for example, your intra-dominal pressure goes up to about 170 millimeters of mercury.

14:31 [SPEAKER_01]: So about three times, just standing and performing a Valsava. [SPEAKER_01]: And a resistance training, research shows that when you hit approximately 80 percent of a maximal voluntary contraction, not necessarily a 1-ret max, but you could use that sort of proxy. [SPEAKER_01]: your body will reflexively do of all solvemenover, again, to not only produce force and transmit force more rigidly, but perhaps as a sort of protective mechanism against a moving under load.

14:56 [SPEAKER_01]: And again, this happens in day to day tasks, not just in the gym. [SPEAKER_01]: This has been directly studied in a variety of very interesting ways where they place catheters in all sorts of places that you wouldn't want them otherwise. [SPEAKER_01]: I'll let you guys figure that out. [SPEAKER_01]: But when subjects were told to lift, maximum load's not necessarily in the gym, but, you know, whether it's a box or create something like that.

15:15 [SPEAKER_01]: And even when they weren't given any breathing instructions, they instinctively performed a Valsava maneuver. [SPEAKER_01]: And also, in studies, where they actually coach people to breathe in during one part of the lift and breathe out during another part of the lift, you know, breathe in on the way down, out on the way up.

15:32 [SPEAKER_01]: People still do this [SPEAKER_01]: And again, this bears some importance when we discuss, like, advice to the contrary to not perform of all solvva maneuver. [SPEAKER_01]: So given the reflexive nature of the Valsava maneuver, when humans exert themselves, Austin, where do you think the advice to breathe in on the way down and out on the way up even come from?

15:53 [SPEAKER_00]: I think a combination of a lack of understanding of some of this kind of subconscious reflexive element of this, but there's some extent to which there is a degree of control, you know, I think that becomes less and less controllable with higher and higher intensity demands, right? [SPEAKER_00]: And so it almost ends up being like a way to lease yourself for it's like pull the reins back on like how hard you can actually exert yourself out of just fear of, [SPEAKER_00]: You know, people see what your face looks like when you're bracing really hard And potentially some concern over blood pressure increases even though again as we've talked about before like all exercise Increase your blood pressure while you're doing it

16:29 [SPEAKER_00]: They're, to the, whatever extent, there's a matter of degree. [SPEAKER_00]: And somebody might perceive or believe that less of a blood pressure excursion may be safer than a greater blood pressure excursion. [SPEAKER_00]: Again, not saying that's necessarily the case, but if that's somebody's belief system, then they might say, well, if I have you do this, it'll limit how hard you can go, limit your intensity, limit the intensity of al salva, maybe limit this blood pressure excursion.

16:51 [SPEAKER_00]: Maybe it's like a chain of reasoning based on maybe a premise where they think that that'll lead to, you know, a safer experience down the line. [SPEAKER_01]: Yeah, there was some interesting studies where they were looking at people again, just what they would do habitually when they were asked to do a some sort of lifting task.

17:06 [SPEAKER_01]: And even when they were coached to, you know, breathe in on the way down, breathe out on the way up. [SPEAKER_01]: There'd be like a pause in the exhalation, almost like they're doing like a miniature mini vowel vowel on the way up. [SPEAKER_01]: Again, it's just reflexive and you can't really undo the reflex.

17:20 [SPEAKER_01]: But yeah, to your point, if you were trying to put like a, you know, [SPEAKER_01]: a barrier against a can't lift above a certain point where you do an of all saw for whatever reason. [SPEAKER_01]: Yeah, I suppose that's reasonable, but you better not take that weight anywhere in your failure.

17:33 [SPEAKER_00]: Totally. [SPEAKER_00]: I mean, it's like in in certain rehab context, for example, where I might say you're going to do a set of 12 with a 530 tempo or something. [SPEAKER_00]: It's like, try to go heavy on this. [SPEAKER_00]: Like, I don't see that happening, right? [SPEAKER_00]: It's another way to do that.

17:45 [SPEAKER_00]: If we [SPEAKER_00]: I could just as easily an rehab context. [SPEAKER_00]: I don't want you to squat a set of 10 where you can like breathe continuously throughout the entire rep or something. [SPEAKER_00]: That would just be another way that I could like put reins on somebody and pull back on them so they can't go too hard to soon.

17:58 [SPEAKER_01]: Yeah. [SPEAKER_01]: So that's the story with reflexive all-solves, but what about an intentional or consciously performed ball-solvo maneuver? [SPEAKER_01]: The intentional Valsalmanover does tend to create higher interabdominal pressures than normal breathing or reflexive bracing at sub-maximal loads.

18:13 [SPEAKER_01]: So if you're squatting 70% or lifting 70% for example, doing this consciously is going to produce a higher interabdominal pressure than what you would do reflexively. [SPEAKER_01]: But once the weight gets heavy enough, [SPEAKER_01]: The differences are not substantial. [SPEAKER_01]: So we think around 90% of a one-ret max, the difference between intentional and reflexive ball-solve maneuvers, effect on the intro abdominal pressure kind of shrinks.

18:37 [SPEAKER_01]: Basically, by the time you're maxing out, the reflex is so robust that it's going to happen regardless of what you're telling your glottis to do in the back your throat. [SPEAKER_01]: In sport, the Valsov maneuvers often use to anticipate the load rather than react to it. [SPEAKER_01]: So, has to do with the sort of timing, the pressure, with the initiation of the lift, or the effort, something like that, mainly to improve efficiency and coordination.

18:59 [SPEAKER_01]: So, if you train yourself to do it, it tends to be a result in a more efficient movement pattern, more efficient performance. [SPEAKER_01]: And adding a belt, [SPEAKER_01]: On top of that, also seems to increase intrabidominal pressure. [SPEAKER_01]: We said that baseline just standing up right, the intrabidominal pressure is about 20 millimeters of mercury.

19:16 [SPEAKER_01]: If you just do a Valsava while you're standing up right, it's about 65 millimeters of mercury. [SPEAKER_01]: If you were to jump, it's about 170 millimeters of mercury. [SPEAKER_01]: Doing 90% of your one-right max deadlift, when this has been tested directly, with no belt, the intrabidominal pressure is about 156.

19:34 [SPEAKER_01]: millimeters of mercury in this particular study. [SPEAKER_01]: And then with a belt, it was 175. [SPEAKER_01]: And so it's not that much different than jumping or sneezing or coughing, you know, for example, but the duration is obviously going to be a little bit longer. [SPEAKER_01]: And again, these are intentional ball-solving maneuvers, not reflexive.

19:51 [SPEAKER_01]: So Austin, you know, if doctors are worried about doing of al-Sava while lifting, how do they justify a patient's sneezing or jumping in an unrestricted manner which generally generates a similar if not greater increase in intrapetimal pressure? [SPEAKER_00]: Yeah, I mean, I think it's a combination of like, how much do they know about this?

20:08 [SPEAKER_00]: But also the fact that one is volitional or by choice the other's not. [SPEAKER_00]: And then, yeah, to your point, duration, usually the lifting one is going to be longer and duration, especially. [SPEAKER_00]: cumulative exposure, if you're doing more than one effort or multiple reps sets or something like that, compared with us needs or two, or maybe three, or a jump that might be brief, very transient and self resolving if they're thinking about this in terms of like a cumulative exposure or a dose response type thing, a lot of this is kind of physiologic hypothetical reasoning compared with anything that has like direct outcome evidence to support it for sure though.

20:41 [SPEAKER_01]: Yeah, let's get into it and I think to truly understand why your doctor, your trainer, and maybe even your mom tell you not to hold your breath when you live, we have to look at the evidence through their eyes. [SPEAKER_01]: To me, the primary concern is usually blood pressure, and if I'm the prosecution, the primary piece of evidence is that 1985 McDougall study, again, they used intra-artorial catheters to measure the blood pressure people doing near [SPEAKER_01]: which, again, if I ever saw that on a blood pressure cuff, I would like, firstly wouldn't believe it.

21:16 [SPEAKER_00]: I think I broke the need confirmation for sure, but yeah, I would certainly get your attention. [SPEAKER_01]: Yeah, for sure. [SPEAKER_01]: So that's like the primary concern and then there's a secondary concern where the thought is like there's some inconsistent pressure because some argue that the high pressure that we create in our chest and in our abdomen that intro, the rassic and intro abdominal pressure, [SPEAKER_01]: Some people argue that's like a pressurized suit that supports the blood vessels and their increased blood pressure during a valsal manure from the outside, but people will say that's inconsistent support.

21:49 [SPEAKER_01]: They believe that while the pressure inside your arteries is going up, the external pressure, the squeeze from your lungs, your gut, with the fluid in your brain, might not rise perfectly in lockstep with it or fast enough to match it. [SPEAKER_01]: and this creates a high-transmural pressure gradient, essentially a massive pressure gap between the inside and the outside of the vessel, which could cause the vessel to rupture.

22:11 [SPEAKER_01]: And on top of that, exercise guidelines are generally geared towards the general population, and it's estimated that like one in 50 people have an undiagnosed [SPEAKER_01]: And for these individuals, the concern is that a max effort Val-Sauve maneuver sends a high velocity pressure wave directly to a potentially weak point in the brain's vasculature right to the circle of willis, right?

22:35 [SPEAKER_01]: And then there's an additional concern that involves the release of the Val-Sauve maneuver just as much as the actual hold. [SPEAKER_01]: Moving from this extreme pressure of the lift with the Valsalva maneuver to a sudden vacuum where you exhale creates this vascular shear stress and if someone had a subclinical plaque, perhaps that turbulence could theoretically dislodge a plaque that could lead to an eschemic stroke for example.

22:58 [SPEAKER_01]: And then lastly, there's the risk of fainting by severely impeding blood return to the heart cardiac output can drop solo that the brain shuts down as a survival mechanism. [SPEAKER_01]: Passing out while supporting a heavy barbell introduces a high risk of secondary traumatic injury. [SPEAKER_01]: For example, there's other concerns around the heart.

23:15 [SPEAKER_01]: Oh, it's just bad for your heart. [SPEAKER_01]: It's got to be bad for you. [SPEAKER_01]: But Austin, when you weigh these potential outcomes against the relatively minor gain and trunk stiffness with the intentional Valsava, it could be viewed as this unjustified risk. [SPEAKER_01]: Am I missing anything?

23:29 [SPEAKER_01]: If you were talking to another doctor, how would you go about determining whether or not the Valsava maneuver is worthwhile or not? [SPEAKER_00]: Yeah, I don't find myself having this conversation as often with other doctors and more often with patients and in that context, it comes down to like, well, what is the goal?

23:44 [SPEAKER_00]: What's important to you? [SPEAKER_00]: What are we trying to accomplish? [SPEAKER_00]: Because if the question was, like, go back to the meme photo of myself pulling a fourth, I think that was like a set of six, twenty deadlifts for a set of four, and that was like the final rep that was like pretty difficult.

23:58 [SPEAKER_00]: Is that necessary for health outcomes, certainly not, right? [SPEAKER_00]: And that's not something that, you know, is you're ever going to see in like general population physical activity guidelines of you need to reach that level of exertion to improve health outcomes because that's just not going to be something that's necessary.

24:17 [SPEAKER_00]: On the other hand, if these risks were manifesting at the rate that might be expected based on this line of reasoning, just based on the prevalence of some of those things that you describe, the baseline prevalence population prevalence of undiagnosed aneurysms of atherosclerotic plaque, things like that, we should actually see a much higher amount of, [SPEAKER_00]: Injuries, incidences of these things, of cardiovascular events, of non-traumatic, subaract noise, hemorrhages in the brain, as a result of people doing, Valsalva is not just in the gym, but from just routine exposure in day-to-day life.

24:53 [SPEAKER_00]: Now certainly these things can happen from time to time, but there has to be more to this if the prevalence of the kind of dreaded outcome that we're fearful of that we're advising people to avoid this as a result of that fear. [SPEAKER_00]: If it were really as likely as the kind of that recommendation would presuppose we should be seeing a lot more of it and we don't and I'm not saying that I have all the answers or all the perfect explanation for why maybe it doesn't You know, linearly pan out in the sense in the way that might be predicted from like baseline physiologic principles of like what is blood pressure due to wall stress and things like that.

25:27 [SPEAKER_00]: but just there clearly is something there and then some of it just might be like stochastic, probabilistic, going to sort of things. [SPEAKER_00]: But that's why I'm less apprehensive about these things in terms of their trade-offs, especially if Davos Alva is kind of in keeping with the person's goals.

25:45 [SPEAKER_00]: So meaning that somebody's like really values performance and I don't assess them to be at some catastrophically high cardiovascular risk otherwise that they have like, you know, [SPEAKER_00]: a five plus centimeter, you know, thoracic aneurism that's like, you know, needing to potentially get impending, you know, repair or something like that.

26:02 [SPEAKER_00]: Yeah, we're going to have a little bit of a different conversation that's in that context. [SPEAKER_00]: Mainly because I'm not the person that they should be talking to, but you know, they should be getting, you know, expert advice from the person who would be offering that procedure to them.

26:13 [SPEAKER_00]: So that's kind of some of my thoughts on this topic. [SPEAKER_00]: It's a complicated one, not one that I have a clip would claim to have all the answers to, but [SPEAKER_00]: Gosh, if it were as simple as a lot of that kind of logic would presuppose, we should be seeing way more of these things happening in the real world.

26:26 [SPEAKER_01]: Yeah, and again, I always come back to this idea, like, okay, well, if we do suppose that there's some non-zero risk, right, and it is definitely not in keeping with the person's goals to expose them to that risk. [SPEAKER_01]: Mainly, they're like, I'm just doing this for health, performances as, you know, [SPEAKER_01]: secondary goal, like I like it, but you know, I just, I'm really just doing this for health.

26:46 [SPEAKER_01]: And so then you'd say, oh, I will look. [SPEAKER_01]: We're not willing to accept any risk from this. [SPEAKER_01]: It's kind of like the mixed grip use in the desert. [SPEAKER_01]: You're like, okay, just use straps. [SPEAKER_01]: Because this is reflexive. [SPEAKER_01]: Then you're also signing this person up to use lighter weights, not-go closer to failure, and perhaps now you're compromising the actual benefits of the exercise intervention itself because it's going to be underdosed.

27:12 [SPEAKER_01]: It's going to be very challenging to make up for that if possible at all. [SPEAKER_01]: I just don't think there's a way to train productively for most folks that completely remove the volume over because, again, it's reflexive. [SPEAKER_01]: It's just not going to be hard enough. [SPEAKER_00]: No, yeah, a great, completely removing it is not really a realistic thing to recommend for like life in somebody.

27:30 [SPEAKER_00]: If in compatible life, yeah, as you've said before, if there's a situation where truly performing any degree of bracing Valsalva, even instantaneously, is a threat to your life like you ought to be probably in a cardiovascular ICU. [SPEAKER_01]: Yeah, yeah. [SPEAKER_01]: If you were like, what are the pre-exercise screening criteria?

27:48 [SPEAKER_01]: I really need to meet. [SPEAKER_01]: So I know that I can exercise safely. [SPEAKER_01]: I'm like, all right, look, if you can ambulate, move about your environment without much assistance. [SPEAKER_01]: If you can go to the bathroom without much assistance, [SPEAKER_01]: Right, and you're able to consciously make your own decisions.

28:04 [SPEAKER_01]: I think you can exercise. [SPEAKER_01]: There's probably way for you to exercise. [SPEAKER_01]: Yeah. [SPEAKER_01]: If any of those things are compromised, you probably need to be in a, you know, in some sort of observatory unit in a medical facility because you're impending surgery, if you have some sort of emergent condition.

28:17 [SPEAKER_01]: Agreed. [SPEAKER_01]: All right. [SPEAKER_01]: Well, let's look at the opposite side. [SPEAKER_01]: That was looking at this issue through the lens of somebody's very concerned about risks. [SPEAKER_01]: So what does the science say? [SPEAKER_01]: Because easy to look at the blood pressure numbers, like 480 over 350 in a soon, a blowout is imminent.

28:33 [SPEAKER_01]: But focusing solely on the internal blood pressure ignores the most important variable in vascular safety, trans mural pressure. [SPEAKER_01]: A blood vessel doesn't fail just because the pressure inside of it is high, it tends to fail when the pressure inside significantly exceeds the pressure on the outside of the vessel.

28:51 [SPEAKER_01]: So if you have 400 millimeters of mercury pushing out, but 390 millimeters of mercury pushing back in, the actual stress on the arterial wall is pretty much negligible at that point. [SPEAKER_01]: And in the gym, we do, in fact, create a high pressure environment that surrounds and supports maybe even cradles the vascular system.

29:10 [SPEAKER_01]: Austin, this concept of a pressure gradient, the trans mural pressure across the blood vessel wall or any space in the body really, that's very important. [SPEAKER_01]: Can you break that down for our listeners? [SPEAKER_00]: Yeah, I think you actually did a perfectly fine job of describing it already.

29:25 [SPEAKER_00]: Pressure gradients are how things move that, you know, that's the same way as I described of how we breathe, for example, which generated pressure gradient between the outside environment and our lungs and so air rushes in and then when we're ready to breathe out, we increase pressure in our chest and air goes back out.

29:41 [SPEAKER_00]: the same way our heart generates blood flow increases the pressure squeezes down blood flows out lowers the pressure by relaxing blood fills it back up again so pressure gradients is a a very important part of life and so trans mural is just a fancy way of saying [SPEAKER_00]: across the wall.

29:58 [SPEAKER_00]: And so the pressure difference across the wall of a blood vessel is the physiologic parameter that we're talking about here that is of interest when having this type of conversation doesn't need to be too much more complicated than that, at least for our purposes here today. [SPEAKER_01]: Yeah.

30:12 [SPEAKER_01]: All right. [SPEAKER_01]: So let's look at some evidence on this trans mural pressure gradient. [SPEAKER_01]: So one study had dudes do leg presses again. [SPEAKER_01]: It seems to be a very common exercise amongst the exercise scientists. [SPEAKER_01]: It was pretty heavy too. [SPEAKER_01]: 80% and 100% of their one rep max while using an ultrasound to watch their heart during the Valsov maneuver while they were exercising.

30:32 [SPEAKER_01]: And while blood pressure skyrocketed, distress on the heart walls remain stable or decreased if they measured it by ultrasound. [SPEAKER_01]: Why did this happen? [SPEAKER_01]: Well, the high pressure inside of the chest actually pushes back against the walls of the heart. [SPEAKER_01]: So it's the walls of the heart wall is contracting are trying to, you know, go outward outwardly, but you've got this high pressure system on the other side that prevents that from becoming too great.

30:57 [SPEAKER_01]: There's also direct measurements that show the intra-therasic pressure surrounding the Aorta. [SPEAKER_01]: That's the major blood vessel coming off of your heart. [SPEAKER_01]: That increases one to one with its internal pressure, preventing the vessel from overexpanding. [SPEAKER_01]: In the brain, we talk about external pressure, protecting the brain, we're really talking about cerebral spinal fluid or CSF.

31:17 [SPEAKER_01]: You can think of your brain as an object, kind of floating in a bath of clear fluid, and this fluid surrounds the brain and every single blood vessel inside your head. [SPEAKER_01]: On the other side, you have your skull. [SPEAKER_01]: This is rigid, boney box. [SPEAKER_01]: It doesn't expand, at least we hope not.

31:31 [SPEAKER_01]: And the volume inside of your skull is, therefore, fixed. [SPEAKER_01]: If you try to cram more stuff or more anything into that box, the pressure of the fluid has to go up. [SPEAKER_01]: So when you perform a Valsava, the high pressure in your chest acts like a dam. [SPEAKER_01]: It makes it harder for the blood to drain out of your head through your jugular veins.

31:50 [SPEAKER_01]: And this causes a momentary resistance to flow of the blood that's inside your skull. [SPEAKER_01]: Because that fluid has nowhere to go, the pressure inside the skull, the intracranial pressure goes up. [SPEAKER_01]: which gets passed on to the cerebral spinal fluid, again, that's the fluids around your brain and blood vessels.

32:06 [SPEAKER_01]: And this is the pushback. [SPEAKER_01]: You have blood pressure pushing out from the inside of the artery, but you have an equal spike in the fluid pressure pushing back from the outside. [SPEAKER_01]: And the result, when it's measured, [SPEAKER_01]: is that your cerebral perfusion pressure remains remarkably stable with the Valsal maneuver which has been directly investigated.

32:24 [SPEAKER_01]: Also using some fancy technology called Transcranial Doppler, this looks at blood flow. [SPEAKER_01]: Researchers observed that cerebral blood flow is well maintained during the initial phases of a Valsal maneuver. [SPEAKER_01]: A significant drop in flow only occurs if the strain has held long enough to reach this late phase 2 effectively.

32:42 [SPEAKER_01]: You're holding it all solve them over for like 15 seconds, 20 seconds, something like that. [SPEAKER_01]: Where cardiac output finally begins to fall. [SPEAKER_01]: And this is really where we see some of that syncopy risk. [SPEAKER_01]: Start to come up. [SPEAKER_01]: There is some nuance here when you release the air, particularly if it's done quickly, intercranial pressure and entertherasic pressure dropped to zero or very low almost instantly.

33:05 [SPEAKER_01]: And so there can be an overshoot, which Austin talked about earlier, your systemic blood pressure stays high because the heart is suddenly pumping a huge volume of blood into that still constricted blood vessels. [SPEAKER_01]: So you have this high internal pressure and low external support.

33:19 [SPEAKER_01]: Theoretically, that would be the highest risk of something bad happening because that transmiral pressure could be higher. [SPEAKER_01]: But again, where are the bodies? [SPEAKER_01]: I Austin, most people have seen the meme of you deadlifting with your eyes popping out. [SPEAKER_01]: Can you explain this based on the mechanisms that we've talked about so far?

33:37 [SPEAKER_00]: Yeah, I mean, that's kind of the image that I had in my mind when you're describing increases in intracranial pressure and obviously it's very fortunate that we have this kind of balancing mechanism to maintain relatively stable cerebral profusion pressure as a very important variable that is basically a fancy physiologic term that describes the ability of blood flow to get into your brain and keep you awake and conscious.

34:00 [SPEAKER_00]: And this is why during those very high intensity efforts is not when we tend to see quite [SPEAKER_00]: single episodes and things like that. [SPEAKER_00]: But also the eyes and everything there are all kind of in very close neighborly proximity to these other structures and pressure can get transmitted in all sorts of different ways.

34:17 [SPEAKER_00]: And so yeah, I think that I might have a little bit of an above average tendency to have some of that proptosis as a way we can describe it as my eyes bulging out a little bit more when under that degree of pressure. [SPEAKER_00]: And fortunately, they go back in afterwards. [SPEAKER_01]: I seem to recall an episode of you, I believe you were dead lifting, but you might have been squatting.

34:35 [SPEAKER_01]: I don't know if this is revisionist history, and you had contacts in, you actually like jettisoned a contact from your eyeball. [SPEAKER_00]: Yeah, that's happened to handful of times actually over the years. [SPEAKER_00]: And I remember one of my earlier powerlifting meets that I did. [SPEAKER_00]: I think it was after the first time I moved to San Antonio for residency training now over a decade ago at this point that I actually did the whole meat wearing regular like eyeglasses instead of contacts because I was worried that in the middle of the meat I was going to pop a contact out and that was in a powerlifting gym not going to be a contact that I chose to pick up off the ground and put back into my eyes.

35:09 [SPEAKER_00]: So I just wore eyeglasses for the whole meat. [SPEAKER_01]: But I've been a great case study, you know, what weird infection do you get in your eye? [SPEAKER_01]: Well, probably microbial is what I would say, 100%. [SPEAKER_01]: Yeah, so that's the sort of pressurized suit defense that we're going to keep referencing, but there's also some thought that doing the Valsalva is bad for your heart.

35:28 [SPEAKER_01]: Can't be good for you. [SPEAKER_01]: You know, due to the increase in blood pressure that occurs with all exercise, but markedly with resistance training, and then it's even higher with the Valsalva number. [SPEAKER_01]: Perhaps this causes left ventricular hypertrophy or LVH. [SPEAKER_01]: and that theoretically could be avoided if you didn't do the Valsal maneuver when you lifted weights.

35:49 [SPEAKER_01]: So, left and trickle are hyperch fees that thickening and stiffening of the heart's main pumping chamber, your left ventricle, which would reduce its efficiency and can lead to heart failure or with me as heart attack or stroke. [SPEAKER_01]: Now, the heart does change relatively quickly in response to training.

36:06 [SPEAKER_01]: That's been well-characterized for years. [SPEAKER_01]: However, historically there's been some weird data around this. [SPEAKER_01]: We covered this in our extreme exercise hypothesis podcast. [SPEAKER_01]: I think it was episode 215. [SPEAKER_01]: I'll link that in the show notes. [SPEAKER_01]: But there's a thought that [SPEAKER_01]: the changes at the level of the heart were markedly different between endurance training and resistance training, endurance training caused all four chambers of the heart to grow kind of equally, and resistance training only caused a handful of the chambers to get thicker and not necessarily grow in size.

36:36 [SPEAKER_01]: This eccentric versus concentric hypertrophy difference. [SPEAKER_01]: Yeah, that was just based on faulty analyses and not as sophisticated imaging techniques. [SPEAKER_01]: And so what we see now in high quality studies, they don't really support the idea that lifting alone causes this pathological thick walled, small chamber, left ventricle or left ventricular hypertrophy that you see, most commonly in folks with chronic undertreated or untreated hypertension.

37:04 [SPEAKER_01]: That's like the biggest risk factor here. [SPEAKER_01]: Instead, what you see is a similar level of remodeling, and similar style of remodeling that happens with endurance training, unless the individual happens to be using antigenic anabolic steroids, which there are a number of not only small case studies, case control studies, but also case reports.

37:26 [SPEAKER_01]: individuals using anabolic steroids at high doses, in particular, that should be stated where they end up developing this left ventricular hypertrophy and potentially heart failure from that. [SPEAKER_01]: It's not from the Valsalva. [SPEAKER_01]: It's not from resistance training and it just seems to be an effective taking anabolic steroids at high doses.

37:46 [SPEAKER_01]: So Austin, we have extreme blood pressure numbers, wind lifting, and using the Valsal maneuver, but we don't have a trail of dead lifters. [SPEAKER_01]: We also have good data that lifting heavy, which requires the use of a Valsal maneuver, even if it's reflexive. [SPEAKER_01]: We have good data that that reduces resting blood pressure, which suggests against some sort of mechanism of developing left ventricular hypertrophy.

38:07 [SPEAKER_01]: And we also know that the body's vascular system is highly adaptable, like other biological systems. [SPEAKER_01]: So if you were having a peer-to-peer conversation with another physician, who thought the Vosalva maneuver was dangerous during exercise and was telling their patients as much, how would you approach that conversation?

38:22 [SPEAKER_00]: as I do with many conversations, try to figure out where their belief is coming from and assess their epistemology around it. [SPEAKER_00]: What's their level of confidence in that claim? [SPEAKER_00]: And kind of, what is it coming from? [SPEAKER_00]: What are they most afraid of, right?

38:35 [SPEAKER_00]: And then just kind of gently poke at that if there is willingness to engage on the topic. [SPEAKER_00]: I find it super plausible and reasonable to think that high-intensity chronic resistance exercise versus cardiovascular respiratory aerobic endurance exercise will lead to divergent cardiovascular adaptations, and that is related to them having somewhat unique and divergent cardiovascular demands.

39:02 [SPEAKER_00]: So that is very plausible to me. [SPEAKER_00]: But as we've talked about before, one of our favorite phrases is it matters how you got there. [SPEAKER_00]: In the sense that somebody with chronic resting hypertension pathologic hypertension by whatever underlying mechanism, the heart is having a very different experience in working against that chronic high resting blood pressure compared with somebody who might not have hypertension who has a healthy resting blood pressure or maybe who is even training as a part of a way to improve their resting blood pressure, who lowers it yet it's only having [SPEAKER_00]: a handful of brief periodic increases fluctuations in their blood pressure during the course of routine resistance training.

39:41 [SPEAKER_00]: And then for the remaining 23 hours of the day and 365 days of the year, they are not experiencing that same level of thing. [SPEAKER_00]: Those are different ways and different demands and different adaptations that should result. [SPEAKER_00]: And so yeah, I see a lot of heart failure that is [SPEAKER_00]: I have seen precisely zero cases of somebody who squatted bench pressed and deadlifted themselves into heart failure, you know, as an end state.

40:13 [SPEAKER_00]: So similar to the question of where the where the bodies. [SPEAKER_00]: So I remain very open and it actually in support of the idea that there are different adaptations that you can get from these things as a justification in fact in our mind to like people ought to do both this is why we recommend both strength and conditioning if health is the primary goal right doesn't need to be all of one or all of the other.

40:33 [SPEAKER_00]: But if I was talking to a clinician who's deliberately telling people that the vals album universe dangerous and they they should never do it. [SPEAKER_00]: It's just like what are you afraid of and what's at based on and how confident are you. [SPEAKER_00]: Are you open to like reconsidering this and things like that because I think that your patients might do better if we can get them to do more things?

40:48 [SPEAKER_00]: Some of which may actually involve doing this type of maneuver. [SPEAKER_01]: Yeah, and you can slide into Austin's DMs if you are a healthcare professional and he will go through this with you. [SPEAKER_01]: Probably not, but oh yeah, good luck. [SPEAKER_01]: All right, let's pivot here after the break.

41:03 [SPEAKER_01]: We're going to come back and talk about special populations, specifically our individuals at an increased risk of stroke or a ruptured aneurysm and what about individuals during pregnancy? [SPEAKER_01]: Can they do the valsal maneuver? [SPEAKER_01]: All that and more after the break. [SPEAKER_01]: quick break from our podcast, because I want to mention today's sponsor, Caraway.

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42:55 [SPEAKER_01]: We're talking about the Valsalvo maneuver. [SPEAKER_01]: Now, there's this concern that there's an increased risk of stroke and aneurysm when you do the Valsalvo maneuver and you're lifting. [SPEAKER_01]: It's a major concern in healthcare professionals and the public alike. [SPEAKER_01]: We can think of a blood vessel like a high pressure garden hose in that context and aneurysm is essentially like a blister or a thin spot in the wall of that hose.

43:17 [SPEAKER_01]: And over time, we're due to genetics, that specific section of the wall becomes stretched out and weak. [SPEAKER_01]: In the brain, these are often called berry aneurysms because they look like a small fruit hanging off the vessel. [SPEAKER_01]: The fear is that, with the Valsalva, if you suddenly crank the pressure up inside that host, a 400mm mercury that thin, weak, blister will finally give way and burst.

43:38 [SPEAKER_01]: This is the pop that everyone is afraid of. [SPEAKER_01]: This is called a hemorrhagic stroke, where blood escapes the vessel and enters the brain tissue or the space surrounding it, it's a plumbing failure, where the pipe bursts under pressure. [SPEAKER_01]: There's another type of stroke called an ischemic stroke, which is from a blockage.

43:54 [SPEAKER_01]: This is much more common in daily life about 87% strokes are ischemic, and this is when our clog or a piece of debris like a plaque breaks loose and blocks the flow of the blood to the brain. [SPEAKER_01]: The concern here is that the turbulence of the breath hold and release might shake a piece of plaque loose.

44:11 [SPEAKER_01]: The link between Valsovmanover and Stroke is largely based on theoretical speculation, mostly mechanistic type reasoning. [SPEAKER_01]: When we look at actual outcomes, the incidence of cerebral vascular accidents in lifters is exceedingly low. [SPEAKER_01]: Most evidence here comes from isolated case reports, and these almost exclusively involve people with undiagnosed vascular malformations, like bury aneurysms.

44:34 [SPEAKER_01]: And again, we had that transmurral protection. [SPEAKER_01]: the fear of having a pop assumes that the high internal pressure against low external pressure. [SPEAKER_01]: But in reality, the cerebral spinal fluid pressure rises nearly instantly to offset that internal spike in pressure.

44:50 [SPEAKER_01]: So, Austin, based on the available data regarding strokes occurring during exercise and maybe more generally, it seems like a focus on acute changes in blood pressure, misses the force for the trees. [SPEAKER_01]: Instead, people should focus on chronic risk factors, right? [SPEAKER_00]: compelling risk factor data for the incidence of stroke, chronic hypertension is number one, two, three, four, five on that list of risk factors as the thing that we need to spend the most time addressing.

45:19 [SPEAKER_00]: It's interesting, you know, for all the kind of biohacker optimization space and how much interest there is for them, for example, in like, [SPEAKER_00]: wearing continuous glucose monitors and minimizing glucose spikes how wearing a continuous ambulatory blood pressure monitoring or something like that has not taken off in that space and keeping their blood pressure as low as possible for as long as possible.

45:41 [SPEAKER_00]: I think that people, you know, obviously there's the visual evidence when you're doing a hardvel salva against a heavy load, like seeing the face, the contortions, the discomfort. [SPEAKER_00]: I think people would be very surprised if they were to learn the degree of fluctuations that can be physiologic, normal, or sometimes abnormal, that they experience, but never know about just in their day-to-day life.

46:02 [SPEAKER_00]: You know, blood pressure spike that happens while you are maybe you're in traffic and you have a near-miss or a near-accident, or somebody passes you and pisses you off while you're on the road, or other forms of life stress, work stress, all sorts of other things. [SPEAKER_00]: surprised and to know that their blood pressure fluctuates minute to minute throughout the day a lot more than they probably think and yet focusing on this as a unique risk factor mainly based on fear and like facial evidence of strain.

46:38 [SPEAKER_00]: It is an interesting phenomenon. [SPEAKER_00]: I understand how we got here. [SPEAKER_00]: I understand how this happens. [SPEAKER_00]: But recognizing the bigger picture here of chronic resting hypertension is the thing that we ought to spend probably the most time worrying about. [SPEAKER_00]: The situations where these acute fluctuations become more concerning are the situations that we alluded to earlier where it's like, you probably ought to be in an ICU and like, impending surgery or something like that, right?

47:05 [SPEAKER_00]: And that's just so uncommon compared with the proportion of people out there who stand to benefit from doing these types of activities that Yep, it's going to require a bit of blood pressure increase if you want to support some exercise and to whatever extent their may or may not be some risk associated with that.

47:19 [SPEAKER_00]: Again, we're not seeing the trails of bodies and instead we see a very ample evidence of benefit from people being able to participate in these things over a long periods of time. [SPEAKER_01]: Yeah, in fact, it could be a huge red flag if you were to initiate exercise and your blood pressure couldn't go up.

47:33 [SPEAKER_01]: You know, like the same thing as if your heart rate can't go up. [SPEAKER_01]: You know, this sort of a relationship is a huge red flag in practice. [SPEAKER_01]: So yeah, again, I get why how we got here and I get the theoretical concerns, but then immediately we should look at, all right, what does the outcome data?

47:51 [SPEAKER_01]: It's like, oh, I guess I just have to reject that hypothesis. [SPEAKER_01]: And perhaps it was incomplete logic. [SPEAKER_01]: Yeah, I think that's the the story on strokes and aneurysms. [SPEAKER_01]: What about the pelvic floor? [SPEAKER_01]: Get this thought out there that look if you do a valsal maneuver, particularly if you're a woman, that's going to cause stress urinary incontinence.

48:08 [SPEAKER_01]: You know, it's going to wreck your pelvic floor. [SPEAKER_01]: Obviously, there's some stuff on social media. [SPEAKER_01]: You can see this happening, right? [SPEAKER_01]: Women who have leakage during a lift, usually a heavy lift for the most part. [SPEAKER_01]: And usually that's co-occurring with those sort of distorted faces as you were talking about.

48:24 [SPEAKER_01]: So there's just a assumption. [SPEAKER_01]: All right, they're doing a ball-solve. [SPEAKER_01]: They're lifting heavy. [SPEAKER_01]: Stressier and air and continents. [SPEAKER_01]: It's causal, right? [SPEAKER_01]: The rooster crow sun comes up. [SPEAKER_01]: Rooster causes sun to grow to come up.

48:35 [SPEAKER_01]: It's missing a few important things that happen. [SPEAKER_01]: One is a reflexive co-activation. [SPEAKER_01]: pelvic floor muscles contract prior to and during the rise of intra-abdominal pressure. [SPEAKER_01]: It's this sort of feed-forward mechanism designed to counteract the downward force of the Valsov maneuver on the pelvic organs.

48:56 [SPEAKER_01]: There's also a weight lifters paradox, power lifters, this has been studied, often have lower rates of incontinence than high impact athletes like gymnasts and runners, suggesting that the impact of landing, or that sort of impulse, is a bigger driver of dysfunction than the pressure of a three second brace.

49:13 [SPEAKER_01]: Also, there's chronic straining when you're on the toilet, particularly for long durations, as much more strongly linked with like something like a pro-lapse than intentional straining during a heavy squat. [SPEAKER_01]: You don't really see pelvic organ pro-lapse there because the Valsalv maneuver is wrecking your pelvic floor musculature, and also by the way, the pelvic floor is adaptable.

49:31 [SPEAKER_01]: Just like other muscle tissue, other tissues in the body, and it does adapt. [SPEAKER_01]: High intributal pressure is a stimulus for adaptation, not just a risk of breaking the floor. [SPEAKER_01]: Again, we're not really like cars. [SPEAKER_01]: We do adapt to what we're exposed to or not exposed to.

49:48 [SPEAKER_01]: There's no real evidence here of al-Sauve maneuver during exercise worsening pelvic floor dysfunction, but it may be provocative. [SPEAKER_01]: I think that's what people are mostly noticing. [SPEAKER_01]: Individuals who are susceptible to whether it's stress engineering, continents, or some sort of pelvic floor dysfunction that may crop up when they're lifting heavier and again, since the of al-Sauve maneuver is reflexive anyway, like this may all kind of go together in their sort of lived experience, but saying that it's causal.

50:13 [SPEAKER_01]: And then further, you should avoid it. [SPEAKER_01]: Again, I think that's really just incompatible with exercise. [SPEAKER_01]: What do you think about that? [SPEAKER_00]: Yeah. [SPEAKER_00]: I mean, it's a fair take. [SPEAKER_00]: This is fortunately something that I think that... [SPEAKER_00]: is not something that I am encountering routinely in day-to-day medical practice.

50:28 [SPEAKER_00]: I think we probably encounter a bit more in coaching practice, but there are folks who can help in these situations whether through coaching, kind of cues and programming methods with some deliberate guidance on that front as well as things like public floor physical therapy. [SPEAKER_00]: Yeah, yep.

50:44 [SPEAKER_01]: We also have a podcast that I will link in the show notes on stress engineering continents. [SPEAKER_01]: You can hear that if you are so inclined. [SPEAKER_01]: All right, this was my most fun part of the podcast for me when I was doing the research because this is near and dear to my heart, not because I am an individual experiencing pregnancy.

51:01 [SPEAKER_01]: But just because I feel charged to take this up. [SPEAKER_01]: Okay. [SPEAKER_01]: Well, I think that, you know, pregnancy is one of those periods of time that women have the most interaction with health care professionals, right? [SPEAKER_01]: And so to me, there's like a lot of, you know, opportunity to do good.

51:18 [SPEAKER_01]: there. [SPEAKER_01]: And exercise is underdosed, under delivered, under utilized in pregnancy. [SPEAKER_01]: And I'm just like, why? [SPEAKER_01]: You know, and I think it just comes back to fears surrounding many different aspects of exercise with respect to not only baby, but also mom.

51:32 [SPEAKER_01]: And that extends to the Valsalva maneuver. [SPEAKER_01]: Look, there's going to be harm to baby by compromising blood flow. [SPEAKER_01]: If you use the Valsalva maneuver when you exercise during pregnancy. [SPEAKER_01]: And if you combine that with the knowledge that this is really an unavoidable reflex at heavier loads then if you were to attempt to avoid it, that might actually, you know, decrease the utility or the efficacy of the training stimulus, which there are known benefits to exercise to mom and baby during exercise and known risks of insufficient activity and so for people to avoid that.

52:07 [SPEAKER_01]: That would be problematic because we know exercise works better for health if it actually works to make you fitter. [SPEAKER_01]: So when we look at actual evidence on things like uterine blood flow, for example, the maternal presser response, that's a fancy way of saying the rise in blood pressure during exercise actually helps maintain the pressure gradient needed to keep blood moving through the placenta.

52:28 [SPEAKER_01]: There's actually a study monitoring individuals who were pregnant lifting up to 90% of their [SPEAKER_01]: There was no evidence, a fetal distress, fetal heart rates, stayed stable, and umbilical blood flow metrics remain normal, another study involving 48 pregnant athletes performing heavy barbell training like sumo deadlifts, for example, at about 76% of their one rat max.

52:53 [SPEAKER_01]: There was only one transient case of fetal rate of cardio, which is a reduction in heart rate, but it resolved quickly and did not meet clinical criteria of concern. [SPEAKER_01]: The study concluded that heavy resistance training is generally well tolerated, although the study did not explicitly record breathing techniques.

53:10 [SPEAKER_01]: The researchers noted that given the heavy loads, many participants likely use the Valsal maneuver instinctively. [SPEAKER_01]: And then there's survey data that indicates that women who maintained their high-intensity training levels, including the use of the Valsal maneuver. [SPEAKER_01]: Until delivery, well, they had reduced odds of pregnancy and delivery related complications [SPEAKER_01]: This is all captured by Acog, the American College of Obstetrics and Gynecology, who they've moved away from like her rate limits on exercise towards RPE rate of perceived exertion and they support strength training, although they don't explicitly say, and you can hold your breath when you do it.

53:48 [SPEAKER_01]: That would be the, that's their final form, right? [SPEAKER_01]: I just think that the historical recommendation for pregnant individuals to avoid the Valsov maneuver and straining, it's largely based on, again, vibes. [SPEAKER_01]: Theoretical concerns regarding uterine blood flow, pelvic floor integrity, fetal heart rates, stuff like that.

54:06 [SPEAKER_01]: The clinical data just doesn't seem to support that. [SPEAKER_01]: Instead, current evidence seems to suggest that for healthy, uncomplicated pregnancies, brief bouts of increased introbdomal pressure during resistance training, during resistance training with the Valsov maneuver is well tolerated, and hasn't been shown to be the primary driver of dysfunction compared to the cumulative load of pregnancy, and the motive delivery, especially with respect to like the pelvic floor.

54:31 [SPEAKER_01]: Does that all make sense to you? [SPEAKER_00]: Do you feel like I'm overthinking on this? [SPEAKER_00]: I think you did a fine job putting that together. [SPEAKER_00]: And I think the wrong message to take away would be to say, ah, well, nothing about training fundamental needs to change when somebody is proceeding through pregnancy.

54:46 [SPEAKER_00]: Of course, the nature of the training, the programming, perhaps the exercise selection, just based on how people feel, maybe the intensity, proximity to failure, may need to change, but that's much more [SPEAKER_00]: based on an individual level, not just based on the binary of pregnant versus non-pregnant.

55:02 [SPEAKER_00]: The training will necessarily need to evolve, but that's more with the person rather than just that binary of the pregnant state. [SPEAKER_01]: Yeah, I think this goes back to just exercise prescription and kind of our view on this in general. [SPEAKER_01]: It's not that the person is pregnant, that connotes, you know, necessitates a change prophylactically.

55:20 [SPEAKER_01]: It's like, okay, now they are preferring different exercises. [SPEAKER_01]: These certain exercises are uncomfortable. [SPEAKER_01]: They don't want to do whatever. [SPEAKER_01]: It's, again, based on the individual, which is independent of pregnancy by and large, because this can happen outside of pregnancy, obviously.

55:33 [SPEAKER_01]: So if we were coming up with a pregnancy template, like how would it look different than our beginner prescription, for example, beginner template? [SPEAKER_01]: It would just have more options, probably, you know, that's what I'm thinking about just more options for people to pick and choose from, rather than like, you can't squat.

55:50 [SPEAKER_01]: You can't hold your breath. [SPEAKER_01]: You can't lift. [SPEAKER_01]: Yeah, and it's like, that doesn't seem to be an evidence-based position to hold. [SPEAKER_01]: The last thing I wanted to talk about is, you know, for performance, as a part of a medicine podcast, we got to talk about lifting, so Austin and your view, we think about the Valsov maneuver, particularly doing an intentional Valsov maneuver.

56:08 [SPEAKER_01]: Do you think there's like a performance benefit, compared to just the reflexive component or reflexive part of a Valsov maneuver? [SPEAKER_00]: I think so. [SPEAKER_00]: You know, there's, I think ample just personal experience are our own experience as athletes, as lifters, as well as as coaches that sometimes even just observing a lifter when they're moving through these exercises, particularly at higher intensities.

56:31 [SPEAKER_00]: There are times when we actually will coach or cue the way that they are bracing in a more deliberate fashion. [SPEAKER_00]: If it was purely the reflex, then it would never be something [SPEAKER_00]: Trust that the reflex is going to do its thing and that it would always lead to kind of like a quote unquote optimal brace and maximum performance, but that doesn't actually seem to be the case.

56:54 [SPEAKER_00]: Yes, it is reflexive, it is automatic to some degree, but that doesn't mean that there isn't room for doing it in certain different ways that might lead to better or worse performance outcomes and so that's something that we've owned probably experimented with our own bracing strategy. [SPEAKER_00]: coaching other people.

57:08 [SPEAKER_00]: Sometimes we watch people and it's like, oh, when they embrace, it seems like they look like they're like holding all this pressure in their face. [SPEAKER_00]: Instead of in their thorac, or their trunk, or their abdomen, it's like, and it's also subtly different compared with how you might do a Valsava to like have a bowel movement.

57:22 [SPEAKER_00]: Like that's not actually what you want to be doing when you're trying to lift a heavy load, the nature of the brace and kind of like, [SPEAKER_00]: I know this is going to be an atomic heresy, but it's kind of like wearing your body you feel it. [SPEAKER_00]: It's a little bit different when you're doing it with her a heavy lift compared to a bowel movement, compared with delivering a baby, compared with a sneeze, compared with a cough.

57:40 [SPEAKER_00]: You know, these things are subtly different. [SPEAKER_00]: And sometimes require some degree of like volitional or conscious kind of queuing coaching modification. [SPEAKER_01]: Yeah, yeah, I don't view this like, oh, we got to fix your brace or we got to, you know, optimize your ball solvenver to be like the key to unlocking somebody's performance, but I do think there's an efficiency bump that's possible there.

57:58 [SPEAKER_01]: Yeah, especially if someone is doing it like really wrong, you know, or really in an inefficient manner, it's just an opportunity to improve performance. [SPEAKER_01]: Yep. [SPEAKER_01]: I agree. [SPEAKER_01]: All right, perhaps a more medically interesting part of this podcast for you, Dr. Baraki, the contraindications to the Valsov manover.

58:15 [SPEAKER_01]: You imagine if I just put 60 seconds on the clock, what are all the absolute contraindications to Valsov manover? [SPEAKER_01]: Let's see how many of them I got and then you can see if there's any more. [SPEAKER_01]: Most medical contradictions for the Valsov maneuver are rooted in mechanistic theory, the fear of the spike in pressure, rather than actual clinical outcome data.

58:35 [SPEAKER_01]: And so absolute contradictions are rare. [SPEAKER_01]: They almost exclusively involve short-term unstable conditions where a sudden pressure spike or the overshoot at the end of a Valsov maneuver poses an immediate threat to some sort of compromise anatomical structure, for example. [SPEAKER_01]: So these would be things like an aortic aneurysm or dissection that is like large or newly discovered, typically greater than like five centimeters, for example.

59:03 [SPEAKER_01]: I think, again, at that point, if you've been recently diagnosed with that, again, unlikely, you just casually go into the gym and wondering, should I do a Valsalva or not? [SPEAKER_01]: I think about if there are times where an acute intra-cranial pressure spike is contrainicated, so recent head injury, recent neurosurgery, symptomatic brain masses, in these cases, the pushback from the cerebral spinal fluid might actually lead to like, [SPEAKER_01]: herniation directly of the brain.

59:29 [SPEAKER_01]: That'd be unusual. [SPEAKER_01]: I'd look for case reports. [SPEAKER_01]: Did not find any fortunately, so that is a fear I no longer have to think about for me. [SPEAKER_01]: If somebody had recent like ocular surgery or retinal detachment, it's another sort of theoretical risk, especially in the early preoperative phase, like after cataract surgery, could disrupt delicate sutures or compromise the healing after an acute cardiovascular event, so like right after a heart attack or during unstable angina chest pain before that has been stabilized or and or revascularized in the case of a heart attack.

1:00:02 [SPEAKER_01]: I think though in most of these cases, you can correct me if I'm wrong. [SPEAKER_01]: Exercise would be restricted anyway. [SPEAKER_01]: So it's not like people like, hey look, you can do any exercise you want, but just don't do a valsal maneuver. [SPEAKER_01]: Yeah, you got this huge, a horticandryism just hanging out, like carry on.

1:00:17 [SPEAKER_00]: Yeah, I think that that's generally the case. [SPEAKER_00]: I think the gray areas here involve not so much the acute things, but when there is a clear risk factor that has been identified for, one of these things, so what if somebody has a established diagnosis of an aortic aneurysm that maybe doesn't meet immediate surgical criteria?

1:00:34 [SPEAKER_00]: What do you do in that situation? [SPEAKER_00]: And I got to tell you, I don't have an answer. [SPEAKER_00]: You know, I don't think that many of us do. [SPEAKER_00]: And so many people [SPEAKER_00]: will air certainly on what they perceive to be a more cautious side. [SPEAKER_00]: I've had patients for example who had a known aortic aneurysm didn't need immediate urgent surgery.

1:00:49 [SPEAKER_00]: And yet they were like, well, I really like training for powerlifting and setting one right max PRs would be better if I trained for, you know, sets of 10 instead. [SPEAKER_00]: I'm like, maybe. [SPEAKER_00]: you know, it might make you feel better. [SPEAKER_00]: I don't know how much of a quantitative difference in risk there might be.

1:01:04 [SPEAKER_00]: There's also the question of like, well, what's our proximity to failure here? [SPEAKER_00]: Does that play a role? [SPEAKER_00]: Maybe. [SPEAKER_00]: I also don't have evidence on this stuff. [SPEAKER_00]: So, you know, I wish I had all the answers and I wish I had a strong evidence to base this on, but we just don't really have that.

1:01:16 [SPEAKER_00]: And so, it seems plausible to me that maybe there is some [SPEAKER_00]: spectrum or gradation in risk and sometimes I try to put myself in that situation and imagine like if I were diagnosed with this aneurysm, how might I go about training? [SPEAKER_00]: If I really wanted to, then it can still be a hard question answer because I'm still imposing some of my own, you know, conscious unconscious biases and preferences on it that may not be applicable to another person.

1:01:39 [SPEAKER_00]: So there are certainly gray areas where people may have to deal with advice that they that they don't like and decide what they want to do with it in their own kind of individual risk [SPEAKER_00]: Yeah, it can even be calculated. [SPEAKER_01]: Yeah, that's the whole thing. [SPEAKER_01]: It seems like a lot of unknown risk.

1:01:53 [SPEAKER_01]: But these acute settings are probably to your point, maybe not the major sort of talking point, rather it's like if someone's got stable coronary artery disease, so some long lasting stuff. [SPEAKER_01]: Is it okay for them to do a Valsava maneuver like we know we have data ultrasound related data showing that Oh look the pressure gradient across the wall of the heart actually is either stabilizer goes down when people do the Valsava And they're lifting heavy weights and also the new American Heart Association guidelines on resistance training Don't mention anything about avoiding the Valsava maneuver and so it's like should we encourage the Valsava maneuver?

1:02:29 [SPEAKER_01]: Should we just take it on a case by case basis and then if so what are our recommendations? [SPEAKER_00]: Yeah, stable corner order disease does not really get me terribly worked up here. [SPEAKER_00]: Now, somebody has anaginal symptoms with it like chest pain with exertion that reliably gets better with rest.

1:02:46 [SPEAKER_00]: There's going to necessarily be some exercise modifications that get put into place there, but we also see evidence. [SPEAKER_00]: that there is still adaptive capacity. [SPEAKER_00]: So for example, when patients who have limb clodication, meaning they get like pain in their legs when they walk because of problem blockages in blood flow, when you put them on like high intensity walking programs and things like that, they actually tend to improve their walking distance and their capacity and pain goes down.

1:03:08 [SPEAKER_00]: And that's probably a result of like kind of subacute to chronic kind of revascularization, neo-vascularization that happens collateral blood flow various other things. [SPEAKER_00]: that can happen in the adaptive process. [SPEAKER_00]: So, yeah, this stable, stable, atherosclerosis is something that is also massively prevalent and often undiagnosed in many people.

1:03:28 [SPEAKER_00]: Like tons of people out there have it and are just like going about their life and even exercising lifting weights, doing all sorts of things. [SPEAKER_00]: And there's a big spectrum in what coronary disease means an atherosclerosis, a big spectrum of what that is. [SPEAKER_00]: But stable disease gets me much less concerned in that context, especially if the person has no symptoms.

1:03:45 [SPEAKER_01]: Yeah, there's also this thought you got to avoid the Valsal maneuver if you're at risk or you have an in-gwinle or abdominal hernia. [SPEAKER_01]: You can't strain. [SPEAKER_01]: know that, except for Ernie is usually the result of like chronic pressure and genetics, not like a three second brace underneath the squat, for example, or deadlift, although certainly can be provocative, but again, it wasn't really the cause, it was just like the straw that broke the camel's back, for example.

1:04:15 [SPEAKER_01]: I think in these cases though, wouldn't necessarily ban lifting, that'd be very challenging for me to say, you can't lift, right? [SPEAKER_01]: You can otherwise live your life, but you can't lift, that'd be challenging, [SPEAKER_01]: I don't know that I would also ban the Valsov maneuver again at least the reflexive components of it.

1:04:30 [SPEAKER_01]: I can probably figure out a program where somebody be unlikely to do much in the way of reflexive, Valsov, but I don't know that I could create an effective exercise program where it's completely eliminated. [SPEAKER_01]: It's just like [SPEAKER_01]: the nature of exercise requires you to transmit force and that's somewhat efficient manner.

1:04:47 [SPEAKER_01]: And if it gets hard enough to work, you're gonna probably do some valsalveline, whether that's intentional or not. [SPEAKER_01]: Yeah, agree. [SPEAKER_01]: But there are any other cases where you think that exercise is not restricted. [SPEAKER_01]: You can do whatever you want, but you have to, you can't do a valsalvel.

1:05:04 [SPEAKER_00]: Yeah, it's a tough one, you know, the way that I tend to organize things is by Oregon system. [SPEAKER_00]: If I really wanted to go through, we've talked a lot about like brain, central nervous system stuff. [SPEAKER_00]: One area we didn't talk a ton about is like the the ear and vestibular system.

1:05:17 [SPEAKER_00]: And so there are sometimes things relating to the vestibular system in the inner ear like. [SPEAKER_00]: semi-circular canal disease, de-hissants, certain other conditions, where it's like there can certainly be like some pressure impacts there that may impact recommendations around develop salvas.

1:05:33 [SPEAKER_00]: If particularly if it tends to be provocative of symptoms, but that's not subtle. [SPEAKER_00]: Like somebody would know if doing a Valsalva, like sends them into a fit of vertigo, for example. [SPEAKER_00]: That's what I'm saying, like not terribly subtle. [SPEAKER_00]: I've talked a lot about it.

1:05:44 [SPEAKER_00]: They have active vertigo. [SPEAKER_00]: All right. [SPEAKER_00]: Yeah. [SPEAKER_00]: Yeah, we talked a lot about the cardiovascular system, the heart, the aorta, the valves, the coronaries. [SPEAKER_00]: With respect to the lungs, you know, I can envision scenarios maybe if somebody is at uniquely high risk of pneumothorax or if they're recovering from a pneumothorax where pressure changes can be potentially problematic that might impact recommendations.

1:06:06 [SPEAKER_00]: And then beyond that, you touched on the hernia question, but really outside of that, there's not a ton more like below the diaphragm that would get me super concerned. [SPEAKER_00]: We've talked a little bit about organ prolapse, whether pelvic organ prolapse in women or if somebody's prone for whatever reason to rectal prolapse and things like that.

1:06:25 [SPEAKER_00]: That's something that generally people are going to want to get fixed. [SPEAKER_00]: You know, before they move on with the rest of their life, doing these things. [SPEAKER_00]: So those are just some of the other things that we hadn't touched on that kind of came across my mind that I might be, [SPEAKER_00]: Disgusting with a patient if there may be some relationship, but again, not subtle things that they probably would identify before I did.

1:06:43 [SPEAKER_00]: Yeah. [SPEAKER_01]: Yeah, I agree. [SPEAKER_01]: All right. [SPEAKER_01]: Well, look, we spent the episode debunking Jim Folklore and talking about the protective pressure I sued. [SPEAKER_01]: Now, how do we actually apply this for the person under the bar or the clinician in the office?

1:06:56 [SPEAKER_01]: Once again, we go back to one of our age-old saints, the body isn't fragile. [SPEAKER_01]: It's multiple redundant adaptable mechanisms in place to not only tolerate the Valsava, but also make it more efficient. [SPEAKER_01]: For healthy populations, I think we both agree that the Valsava maneuver is safe and in some cases, necessary tool to exercise.

1:07:14 [SPEAKER_01]: So for the trainee, [SPEAKER_01]: we would say treat bracing as a skill. [SPEAKER_01]: Don't wait for the reflexive, Valsov maneuver to kick in, but learn to consciously brace before the rep starts, usually during the unwrapped period, to create a stable platform for force production and force transfer.

1:07:30 [SPEAKER_01]: Beginners should learn the intentional Valsov maneuver early. [SPEAKER_01]: This ensures they have the skill ready as the weights increase, rather than being surprised later on. [SPEAKER_01]: uh... i would say the duration should be controlled so you're not doing a balsal maneuver for you know five seconds seven seconds ten seconds at a time prevents the significant drop in cardiac output that occurs with prolonged balsava maneuvers um... also would avoid uh... hyperventilating before a lift generally unhelpful yeah [SPEAKER_01]: Yeah, if you want to cite yourself up, just make sure that you're breathing.

1:08:03 [SPEAKER_01]: Okay. [SPEAKER_01]: And then if you regularly experience light headness after a rep that's something that happens to you, if you like I'm talking about you right now, you can hiss on the way out to to let your air out that can be useful, particularly after a rep for the clinician. [SPEAKER_01]: I think we would both agree that reassurance for worried patients, you know, suggesting you perform reflexive minival sovus daily, when you cough, when you sneeze, and you stand up from a low chair, the system is designed for this.

1:08:33 [SPEAKER_01]: So for a patient that's worried about the valsovum nover overly concerned, some reassurance is usually useful here. [SPEAKER_01]: Would also focus on chronic changes in something like blood pressure, not acute changes. [SPEAKER_01]: I want to exercise. [SPEAKER_01]: You're all your stuff.

1:08:51 [SPEAKER_01]: I should exercise, but look, this blood pressure thing freaks me out. [SPEAKER_01]: You're telling me that my blood pressure can get into the 300's, if I do a lake press or in the 200's, so I'm doing a one arm biceps curl. [SPEAKER_01]: I think you would just focus on the chronic changes to the blood pressure rather than what's happening during exercise.

1:09:07 [SPEAKER_01]: It matters more what happens during the other 23 hours of the day than the one hour per day that you live weights. [SPEAKER_01]: And again, that's sort of a safety valve strategy if people are at high risk for some sort of unwanted event from a Valsalva or perhaps syncopal event passing out afterwards or for people that are apprehensive, this active exhalation or hiss during the concentric phase can be useful.

1:09:31 [SPEAKER_01]: The act like actively queuing a grunt can also work for folks if they can't quite get the hiss or the active exhalation. [SPEAKER_01]: But again, the Valsalva is gonna happen regardless. [SPEAKER_01]: point is, are you going to dump the air, you know, immediately right afterwards? [SPEAKER_01]: Do you need to have a slower release or something of that nature?

1:09:50 [SPEAKER_01]: And then do you want to get the most out of it by doing an intentional one? [SPEAKER_01]: And lastly, for individuals experiencing pregnancy, look without contraindication, you should be exercising. [SPEAKER_01]: That's sufficient intensity. [SPEAKER_01]: It's efficient dose of exercise to see improvements in fitness.

1:10:07 [SPEAKER_01]: Strength, cardiovascular fitness, et cetera. [SPEAKER_01]: And I've all solved when we were going to be a part of that. [SPEAKER_01]: It's reflexive. [SPEAKER_01]: you may experience some discomfort with the Valsava as fetal size increases. [SPEAKER_01]: So again, transitioning to this hiss during the the concentric phase or during the end near the end of the rep can improve that for folks who are training and experiencing discomfort.

1:10:31 [SPEAKER_01]: due to the size of the fetus as it increases during pregnancy. [SPEAKER_01]: But the reality is there's no statistical evidence that Balsava in during resistance training is more dangerous for vascular health than when it's performed reflexively in daily life. [SPEAKER_01]: The pressure I suit logic holds up, the internal spike is matched by the external cradle of support.

1:10:51 [SPEAKER_01]: So for the healthy individual, the Balsava's performance enhancing reflex that protects the spine, the vascular [SPEAKER_01]: For the clinician, the goal should be to empower the individual over avoiding the Valsava. [SPEAKER_01]: Teach patients to manage a pressure rather than fear it.

1:11:08 [SPEAKER_01]: Austin, any closing notes on the Valsava maneuver? [SPEAKER_00]: reasonable take. [SPEAKER_00]: And if people are concerned about a particular medical condition that they have, for example, among that long list of potential contraindications that we talked about earlier, that's where just super individualized advice might need to come into play even if we recognize that some of that advice is not based on [SPEAKER_00]: super compelling, super strong evidence that might be based on your personal risk tolerance or lack thereof, and that's okay too.

1:11:36 [SPEAKER_00]: You get to make these choices. [SPEAKER_00]: Yep. [SPEAKER_01]: Yeah, well said. [SPEAKER_01]: All right, that is a wrap on the Valsov maneuver with Barbell Medicine, special shout out to Dr. Austin and Baraki for joining me on the podcast. [SPEAKER_01]: Before you guys go anywhere, please leave us a five-star rating and a review.

1:11:49 [SPEAKER_01]: It really helps drive traffic to our podcast so we can keep bringing you all the latest nuance and health and fitness. [SPEAKER_01]: Again, I'm Dr. Jordan Vaganbaum. [SPEAKER_01]: We'll catch you next week and every week right here on the Barbell Medicine podcast.