Resistance Training: Too Much May Shorten Your Life

[Ron Put]

OK, the title is a bit of a clickbait, but the studies are real:
 

 

[Ron Put]

Here are the two studies referred to in the video.

I guess an argument can be made for all-cause mortality and increase in risk behavior among super-muscleheads, and perhaps steroids, etc., for the rest, but still...

Muscle-strengthening activities are associated with lower risk and mortality in major non-communicable diseases: a systematic review and meta-analysis of cohort studies | British Journal of Sports Medicine (bmj.com)
 

 

 

Resistance Training and Mortality Risk: A Systematic Review and Meta-Analysis - American Journal of Preventive Medicine (ajpmonline.org)

Edited August 22 by Ron Put

[mccoy]

I just read the BMJ study. My impression is that the database is too heterogeneous, including all healthy subjects of age >18. No specifications were given on their training levels (beginner, intermediate and so on). Also a questionnaire method was used in the original studies. It is not specified what the activities were, so, free body, free weights, machines, bands, or a mixture?

More points.

1. How have been the activity timings calculated? Including or excluding pauses among sets and exercises? Has the accuracy of the calculations been evaluated, if systematic errors prevail (for example, there is a consistent underestimation).
2. What about the subgroups, for example elder beginners may tolerate less time per week than young trained individuals. And an inherent pitfall, a beginners after the followup period may become a trained individual, and what about changes in activity and so on.

Overall, the results are sensible in that there seems to be an optimum in resistance exercise.  I noticed that in myself, anecdotally. Too much of it may lead to overtraining, but a little more may lead to overeating and this would result in increased all cause risk, for example. Professional bodybuilders are surely at high mortality risk, since this is definitely not a healthy sport, messing with metabolism, often using drugs, but the optima still seem too low to me, 45 minutes two times a week falls into a very moderate regime, so it would be better to follow a pretty modest regime according to the metanalysis. Another confounding factor is that longer rests within sets would ensue in higher timings and higher risks according to the study, but more rest would suggest less stress to the system, contrary to the findings of metanalysis.

Edited August 22 by mccoy

[Todd Allen]

5 hours ago, mccoy said:

45 minutes two times a week falls into a very moderate regime

I mostly agree.  But if one does full body moves such as dead lift, squats, clean and jerk, etc. at heavy weights with minimal rest it could be more demanding than someone doing an hour every day of sipping energy drinks between a few sets of 10 bicep curls with light weight.

Edited August 22 by Todd Allen

[mccoy]

Todd, that's it. There are too many variables governing the response to resistance training and it's likely they have not been considered in that metanalysis. 

[Todd Allen]

2 hours ago, mccoy said:

Todd, that's it. There are too many variables governing the response to resistance training and it's likely they have not been considered in that metanalysis. 

Science is more impressive when it is about subjects unfamiliar to us.  Otherwise it can leave us scratching our heads thinking "What have they been smoking?"

[InquilineKea]

Doesn't too much exhaust muscle satellite stem cells? Genesis Lung said something to that effect

Edited August 29 by InquilineKea

[Ron Put]

I agree that the heterogeneity makes it difficult to adjust, but nevertheless, I wouldn't dismiss it.

Other than steroids, there is no specific factor I can think of that would explain why those on the right of the J curve would have a higher mortality. Other than too much strength exercise, that is. It's not like BMI or cholesterol, where you can point to subjects who are close to death and have wasted away, or have depleted cholesterol.

If anything, longer time spent strength training would indicate healthier, stronger subjects, even if a portion of those are mostly strutting around the gym trying to impress. 

The heterogeneity would arguably be a plus here, as it presumably encompasses all manners, from barbells to machines, to body weight and bands.

And for something like the flowing study, steroid use is rather unlikely, IMO:
 

Strength Training and All‐Cause, Cardiovascular Disease, and Cancer Mortality in Older Women: A Cohort Study

 

 

Edited August 26 by Ron Put

[IgorF]

A speculation on the reason - local inflammation that is not easily measurable. The harder people pushing with strenous excercises - the more broken tissue this will create and this is actually a trigger for (re-)building the tissue more intensively and with expanded capabilities.

I suspect there is a lot of proinflammatory signaling on local, cell2cell levels and these things even in specially equipped labs are not easy to assess. Maybe some increased leakage of molecules starts some downstream processes and actually they are not wanted, the same way as so called low grade inflammation. Inflammation has many roles and here probably its signalling, communicative role makes the things happen, these roles are often less obvious (and complicated enough to be hard to study).

That is an easy explanation but as we know they are not working in biology, so it is rather to have some until there will be a better one))

 

Br,

Igor

 

UPDATE: just googled, a quick result https://www.frontiersin.org/articles/10.3389/fphys.2019.01550/full

https://bmcsportsscimedrehabil.biomedcentral.com/articles/10.1186/s13102-022-00397-2

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2933442/

Another layer of simple explanation - moderate level of excercises is beneficial because the body adapts and finishes in more anti-inflammatory state than before https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7188661/

 

more about local inflammation with details

https://journals.physiology.org/doi/full/10.1152/japplphysiol.00971.2016

 

Edited August 28 by IgorF

[Ron Put]

8 hours ago, IgorF said:

A speculation on the reason - local inflammation that is not easily measurable.

Inflammation makes the most sense to me too.

Marathon runners also have higher amounts of deposits in their arteries, which is also at least partially attributed to inflammation, but they may also have wider arteries than controls if I remember correctly. Weightlifters do not get the same extreme cardio benefits to offset the negatives.

[mccoy]

I still regard this study too generic to be of any use. Of course, too much 'muscle strengthening exercise' may be harmful, I think everyone agrees.

However, the results are not broken into age groups, and age is a factor governing muscle strengthening, even the amount of inflammatory processes and the recovery from such processes. 

Even hypothesizing that the results are accurate, the study still is of very little help to those who would like to optimize 'muscle strengthening exercise' for lower mortality.

The optimum dose, says the study, is 40 minutes a week of exercise, but counted how? 40 effective minutes of lifting or pulling, or 40 minutes from the inception to the end of the session, counting the pauses? Unless we are doing supersets with no recovery at all, the two identical timings may represent hugely different doses of exercise.

Also, there is no measure of the intensity of exercise. 40 minutes, however counted, of very light resistance exercise is very different from the same 40 minutes of very heavy loadings. The result on muscle hypertrophy has been proven to be different, the result on mortality is not discernible in this dose-response study, because only the time, not the intensity of the activity is analyzed. In legal medicine, dose-response relationships always consider the amount of time of exposure to a determined harmful agent and the intensity or concentration of such agent.

There are many more details and confounders which have not been taken into account, details which are discussed at length in any bodybuilders' scheme, or even in simple free body exercises. We surely know what are the optimum strategies for hypertrophy (there is more than one) but, after having read the study, we really don't know the best dose, or doses, for optimizing longevity with exercise. 

 

 

[IgorF]

While listening to Huberman's podcast on thyroid and gh "optimization" (=increase metabolism and growth) I noticed that he mentioned he came to conclusions that lifting weights has stonger effect than endurance training and he dug a figure for himself as 60-75 minutes of (as I understood) zone 2 training based on all studies he checked.

His context was - increasing gh and igf1 the best way excercises can do (disconnected from other potential synergies and so on).

If this is correct I can speculate based on this the same way as I did with inflammation, except locality of the molecules production - hormones mentioned are of centralized origin but they will act on all the tissues, including unwanted.

Anyway if mentioned 300-500% temporary gh increase is true then regularly doing it for decades will definitely have some effect on maximum lifespan, thus this could be another plausible contribution factor.

A sidestep - maybe in the context of gh it makes sense to disconnect youth and longevity. The marketers of wellbeing connected wellfeeling with their customer-facing motto and with longevity via feeling healthy, having good capacities and so on as a strong persuasive argument grounded on thousand years old semi-magic perception of things but this is true withing the "average" longevity. If the goal is to try to move outside this average window things should be seen from different angles.

That is IMHO off course, especially the sidestep.

Br,

Igor

 

edited to add:

a limited study for general caucasians population in the US linking higher cancer mortality to gh via height

https://academic.oup.com/biomedgerontology/article/71/6/713/2465560?login=false

(I don't know how to assess gh quantitatively lifelong with and without exercising tuned to max it out, to see how it could add to the sum)

 

more gh: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8255405/

and some quantitative data:

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7245490

->

https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7245484/

so this is not about minute increases, a long practice of more than "recreational activity level" (and probably type) of excercises will definitely rise the absolute gh amounts significantly. This does not mean they will act linear and small but significant effect visible in aggregated data is perhaps consistent with the way it works.

Edited September 7 by IgorF

[mccoy]

6 hours ago, IgorF said:

he dug a figure for himself as 60-75 minutes of (as I understood) zone 2 training based on all studies he checked.

I didn't listen to the podcast, zone 2 refers to endurance-type exercises so I doubt that it can be related to resistance exercise (Inigo St Milan also excludes such a possibility in the recent podcast with Simon Hill). Also, there are many definitions of zone 2, unfortunately. I'm going to put Hubermann's episode in my listening list.

Edited September 7 by mccoy

[IgorF]

Well, Huberman often discussess much wider area of things he really has competence, so it is ok to expect some things that are raiseing doubts. The topic was here https://www.youtube.com/watch?v=x7qbJeRxWGw 

Nevertheless, I just mentioned him as a jumping stone for own thinking about the topic, I have no own interest in it but curiosity drives me to think about it.

Br,

Igor