For the exercise science nerds- lactic acid/cooldown question

[sakfjgadsyukgf]

So, after some Googling around, I learned that modern exercise science says that lactic acid (now called lactate) is not what causes muscle soreness, and is not inherently bad. The 'old' view (that I subscribed to) was that lactic acid directly lead to soreness, but apparently science has moved on from that..... The 'new' view is that soreness is caused by inflammation and microtrauma to the affected muscle groups. OK.

So, I'm typically subject to extreme, ridiculous soreness for days and days after squatting. I've obviously been trying to alleviate that, and this week after squats I did a cooldown that included lighter post-work sets, a bunch of air squats with no weight, and jogging for 5 minutes on the treadmill. (And stretching, but I had always done that post-workout). It was like a night and day difference in how sore I got- the next day, I almost felt like I hadn't worked out at all prior. I had very little soreness and discomfort, and am thinking about upping my training volume & intensity seeing how much better my body feels. The difference is just dramatic. (Strangely, deadlifts never got me anywhere near as sore, even in my lower back).

My question for exercise science nerds is- if lactic acid didn't cause my DOMS, why would an extensive cooldown make me feel so much dramatically better? If it's all caused by inflammation and microtrauma- like, how would a cooldown help microtrauma? You either broke down the muscles or you didn't.....

I want to be pro-science, but my symptoms match the 'old' view of lactic acid and DOMS more than the new one. Just curious what people smarter & more educated than myself think

 

[Badger67]

Google active recovery.
This will steer you where you need to be.

 

[NurseKnuckles]

Google active recovery.
This will steer you where you need to be.

 

[miaou]

The 'old' view (that I subscribed to) was that lactic acid directly lead to soreness

It's not a matter of "old vs new views", it's a matter of what the science says/said and what pseudoscience/broscience/commonmyths say/said.

Muscle acidosis (significant drop of the pH in the muscle) can result in pain because, well, the muscles become acidic and that translates to a "burning" sensation.

It takes several minutes for muscle pH to return to normal (off the top of my head, it could take somewhere in the ballpark of 10-20 minutes, depending on how low your pH dropped, on your aerobic capacity, your buffering capacity, etc.), but that is not related to DOMS and is not related to any pain your might feel hours or days post-exercise.

My question for exercise science nerds is- if lactic acid didn't cause my DOMS, why would an extensive cooldown make me feel so much dramatically better? If it's all caused by inflammation and microtrauma- like, how would a cooldown help microtrauma? You either broke down the muscles or you didn't.....

Pain is a product of the brain. If you think it helps, it probably lowers the pain you feel.

In other words: who the fuck knows.

 

[dsdoubled]

It's not a matter of "old vs new views", it's a matter of what the science says/said and what pseudoscience/broscience/commonmyths say/said.

Muscle acidosis (significant drop of the pH in the muscle) can result in pain because, well, the muscles become acidic and that translates to a "burning" sensation.

It takes several minutes for muscle pH to return to normal (off the top of my head, it could take somewhere in the ballpark of 10-20 minutes, depending on how low your pH dropped, on your aerobic capacity, your buffering capacity, etc.), but that is not related to DOMs and is not related to any pain your might feel hours or days post-exercise.




Pain is a product of the brain. If you think it helps, it probably lowers the pain you feel.

In other words: who the fuck knows.

While I was in school I remember one teacher pointing to lactic acid build up as the cause for muscle soreness and another pointing to trauma from the mechanical action of actin and myosin rubbing against each other. That was in the same semester of the same program. There's always inconsistencies in science. It could be that both schools of thought are correct, but under different circumstances/conditions.

If I had to theorize why your active rest and stretching caused a reduction in muscle soreness, Id say light work you did afterwards helped buffer the lactic acid, shuttle away other waste products and prostaglandins, and increased flow of other beneficial substances to the muscle. While the stretching helped with something called tonicity in the muscle. This just has to do with a muscle's nerve flow, behavior under/after load, and can absolutely contribute to pain/soreness. Different muscles have differing degrees of tonicity so the fact that this approached produced one result for this workout, it may not be as effective after another. If you're feeling curious:

https://triumphtraining.com/blogs/blog/14084217-phasic-vs-tonic-muscles

 

[miaou]

While I was in school I remember one teacher pointing to lactic acid build up as the cause for muscle soreness and another pointing to trauma from the mechanical action of actin and myosin rubbing against each other. That was in the same semester of the same program. There's always inconsistencies in science. It could be that both schools of thought are correct, but under different circumstances/conditions.

What a teacher says doesn't necessarily have anything to do with what "science" says. I've heard plenty of pseudoscientific shit at school.

Can you point to a review published in a reputable scientific journal (even if it was published 20-30 years ago) that says delayed-onset muscle soreness is caused by lactic acid build-up?

 

[dsdoubled]

What a teacher says doesn't necessarily have anything to do with what "science" says. I've heard plenty of pseudoscientific shit at schoolCan you point to a review published in a reputable scientific journal (even if it was published 20-30 years ago) that says delayed-onset muscle soreness is caused by lactic acid build-up?

Of course. Sometimes it does, sometime it does not. And no, Im not aware of any studies confirming or denying that. Why ?

 

[miaou]

Of course. Sometimes it does, sometime it does not. And no, Im not aware of any studies confirming or denying that. Why ?

Because, if you are "not aware of any studies confirming or denying that", then you are not aware of what "science" has (or had) to say on the matter.

 

[dsdoubled]

Because, if you are "not aware of any studies confirming or denying that", then you are not aware of what "science" has (or had) to say on the matter.

Oh I see. So I should disregard everything Ive ever read, seen, heard, been taught by a professor, or learned through experience if it wasn't part of peer reviewed scientific study?

 

[miaou]

Oh I see. So I should disregard everything Ive ever read, seen, heard, been taught by a professor, or learned through experience if it wasn't part of peer reviewed scientific study?

Not necessarily.

But if you haven't read it in peer-reviewed literature, then don't consider it part of "science".

 

[dsdoubled]

Not necessarily.

But if you haven't read it in peer-reviewed literature, then don't consider it part of "science".

I don't know man, feels like youre kinda reaching for some reason to be confrontational. I'll take your advice under consideration though.

 

[miaou]

I don't know man, feels like youre kinda reaching for some reason to be confrontational. I'll take your advice under consideration though.

I'm being matter-of-factual. You might be a bit sensitive to criticism, though.

 

[sakfjgadsyukgf]

It's not a matter of "old vs new views", it's a matter of what the science says/said and what pseudoscience/broscience/commonmyths say/said.

Eh. Not to get into a wider philosophical debate about the nature of science, but I don't think truth in science is as clearcut as you seem to think it is. I would recommend reading 'The Structure of Scientific Revolutions' by Thomas Kuhn, for starters.

Anyways, there's a vast vast difference between (frankly) real and extremely well-studied fields like physics and chemistry. And, poorly-studied and poorly understood quasi-scientific fields like exercise science, nutrition and physical therapy. (Or psychiatry, for that matter- we still don't know *why* SSRIs affect the brain- or even have a theoretical model as to why they should!) There's just a ton of logistical reasons why it's actually really tough to run experiments on a living human body and isolate whether x really caused y. We're basically in the early Enlightenment with some medical/exercise science fields, so I wouldn't get too confident one way or another man. Lactic acid & DOMS is not exactly the theory of gravity.

As a guy with shoulder injuries who's been reading everything on Pubmed he could get his hands on- I was frankly shocked by how little actual research there is in physical therapy, in the 21st century. Many widely-used treatments have like 2 or 3 studies of 12 people, and that's it!

 

[miaou]

Eh. Not to get into a wider philosophical debate about the nature of science, but I don't think truth in science is as clearcut as you seem to think it is. I would recommend reading 'The Structure of Scientific Revolutions' by Thomas Kuhn, for starters.

Anyways, there's a vast vast difference between (frankly) real and extremely well-studied fields like physics and chemistry. And, poorly-studied and poorly understood quasi-scientific fields like exercise science, nutrition and physical therapy. (Or psychiatry, for that matter- we still don't know *why* SSRIs affect the brain- or even have a theoretical model as to why they should!) There's just a ton of logistical reasons why it's actually really tough to run experiments on a living human body and isolate whether x really caused y. We're basically in the early Enlightenment with some medical/exercise science fields, so I wouldn't get too confident one way or another man. Lactic acid & DOMS is not exactly the theory of gravity.

As a guy with shoulder injuries who's been reading everything on Pubmed he could get his hands on- I was frankly shocked by how little actual research there is in physical therapy, in the 21st century. Many widely-used treatments have like 2 or 3 studies of 12 people, and that's it!

All of the above is irrelevant to the matter at hand.

You used the expression "exercise science says that...". The expression "science says", means there is some sort of scientific consensus on a particular claim. On the other hand, if there isn't, nor was, any consensus on a specific claim, then "exercise science" never "said it".

If there are no reviews published in reputable science journals arguing for that specific claim, then there was never any scientific consensus. It was never something "science said". And science never "said" lactic acid causes DOMS.



I know a shitload of coaches thought that (some probably still do). And I am sure some school teacher here and there also parroted that claim. Maybe even a shitty college professor or two. Pretty much all of those people were scientifically uneducated or badly educated.



Case in point, here is what a 25+ year-old review had to say on the subject:

Lactic acid accumulation in the muscles is commonly thought to be the cause of delayed soreness by the lay public. The assumption was examined by Asmussen (1956). His results showed that it was unlikely that excessive production of metabolic substances was the cause of DOMS, as the higher degree of metabolism occurring in concentric or positive work did not cause delayed soreness, only acute muscle pain and fatigue. Later research has confirmed his ideas. Eccentric contractions require lower energy expenditure (Dick and Cavanagh, 1987) and lower oxygen consumption, and they produce less lactate than exercise with concentric contractions at the same power output (Davies and White, 1981). Davies and Barnes (1972) found only a negligible increase in lactate following downhill running. In a later study, Schwane et al. (1983) directly tested the lactic acid theory by comparing lactic acid production and VO2 in subject running at the same speed for 45 min, on a treadmill that was level or inclined downhill. They found that downhill running required significant lower VO2 and produces less lactic acid than level running, but resulted in greater DOMS. Although lactic acid may cause the acute pain associated with fatigue after intense exercise, there is no evidence available to explain satisfactorily how lactic acid produced during exercise can cause the delayed pain which appears 24-48 h later.

link - https://www.tandfonline.com/doi/abs/10.1080/02640419208729932

From a very brief search I found there are reviews from at least the early 80's saying lactic acid has nothing to do with DOMS.
link - https://www.jospt.org/doi/pdf/10.2519/jospt.1983.5.1.10




TL;DR: Re-read my first post.

 

[dsdoubled]

I'm being matter-of-factual. You might be a bit sensitive to criticism, though.

Ok so tell me then, where/how did you come up with the criteria that if the source of any given piece of information is not a scientific study then it can't be considered part of science? That's ridiculous. What about lectures given by respected professors? What about college text books? You're telling me the information gained from those sources can't be considered part of science? I just think that's ridiculous. Should the information gained from the results of a poorly designed, poorly executed, scientific study be considered part of science? And who gets to decide which studies be disregarded and which ones dictate the direction of that scientific field of study. Please, tell me.

 

[miaou]

Ok so tell me then, where/how did you come up with the criteria that if the source of any given piece of information is not a scientific study then it can't be considered part of science? That's ridiculous. What about lectures given by respected professors? What about college text books? You're telling me the information gained from those sources can't be considered part of science? I just think that's ridiculous. Should the information gained from the results of a poorly designed, poorly executed, scientific study be considered part of science? And who gets to decide which studies be disregarded and which ones dictate the direction of that scientific field of study. Please, tell me.

Dude, you need to chill.

 

[dsdoubled]

Dude, you need to chill.

Ok......Im chilled. "Whew!".......

 

[AtlSteel]

Not necessarily.

But if you haven't read it in peer-reviewed literature, then don't consider it part of "science".

This is bullshit. I went through an entire engineering major and didn't read one peer reviewed anything. Pretty sure it was all valid science.

 

[miaou]

This is bullshit. I went through an entire engineering major and didn't read one peer reviewed anything. Pretty sure it was all valid science.

I'm pretty sure you don't realise how science works.

Either way, you also need to chill.

 

[AtlSteel]

I'm pretty sure you don't realise how science works.

Either way, you also need to chill.

If you think something needs to be peer reviewed to be scientifically valid then you don't know what you are talking about at all. If you have any doubts, a quick Google will reveal what crap peer review has turned into. Regardless, it's never been a requisite for the validity of any particular science.