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Exercise intensity influences body composition in healthy older adults (2025)

maturitas.org

141–150 of 194 posts

Re: Exercise intensity influences body composition in healthy older adults (2025)

#141
post #76

Earlier quoted context omitted.

HIIT is a borderline strength training. Consider Tabata protocol. It is supermaximal effort protocol, participants are required to exert maximum effort repeatedly. The duration of active phase of Tabata is 20 seconds, half of approximately 40 seconds after which maximum performance (power output) drops significantly, because body switches to a different energy system. In my experience, Tabata squats are done in range…

So that’s for building muscle, but what about if you wanted to lose a few kilos and increase endurance for long distance running? What would be the way to go to optimise your time?

Eat less to lose the weight. Tirzepatide or something similar makes that a lot easier.

Tabata (the sprint/recover running technique) was developed, I believe, to increase VO2-max. It should help with overall endurance, and you can go on a long run each week. That would probably be efficient.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#142

Earlier quoted context omitted.

I doubt it. In my experience (at least when it comes to lifting), newbie gains last at least a year. Good chance that if they've been untrained all their life (or the majority of it) that phase is gonna last a real long time.

A year of continuous gains for a 72 year old? I highly doubt it. For a skinnyfat 20 year old, sure.

> I highly doubt it.

Not a very convincing discussion point without some support.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#143

I think it's important to note that this study, at least to my understanding, compared cardio training - not weightlifting or resistance training. Participants did 3 weekly sessions of either low intensity, moderate treadmill excercise or HIIT ( 4-min @ 85–95%, 3min 60-70% ). I get the feeling some commenters here are misunderstanding this as a lot of the discussions seems to center about weightlifting. Additionally…

This study is completely unsurprising to me having read a lot of fitness studies over the years. Work muscles harder, muscles get stronger. That is how hormesis goes. The fat loss is simple energy expenditure. You are still producing roughly the same work as someone doing more steady state work. Only effect that might come up is post exercise metabolism elevation but that effect is relatively small and probably prese…

I would have thought the fat loss comes from hormonal changes, not merely the energy used during exercise.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#144

> “High-intensity training reduced fat and maintained lean mass […] though changes were small and not clinically meaningful compared with exercise of lower intensity…” High intensity does border on leading to injury — just making the wrong move — and you’re back to zero intensity?

There is no correlation between exercise intensity and likelihood of injury, this is nonsense. You could e.g. just as well make one wrong move when going for a one rep max.

Going for one rep max is intense. If it weren't, you could get a better max.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#145

Earlier quoted context omitted.

Calisthenics is a really easy way to push intensity at basically 0 risk of injury. They're all compound and depending on the variation could require high reps, but between push ups, pull-ups, squats, their numerous variations, and accessory work, I would challenge anyone to actually injure themselves while also being able to push to true technical failure.

It is very possible to injure yourself with calisthenics. Shoulder impingement or tendinitis from pullups with too much intensity/bad form for example. Weight is weight.

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Re: Exercise intensity influences body composition in healthy older adults (2025)

#146

Earlier quoted context omitted.

> This is directionally incorrect. Your body will burn both concurrently. For aerobic exercise, your body gets around 95% of the energy from burning fat. If you are doing exercise where you are 50/50, then it is by definition no longer aerobic exercise but anaerobic. Anaerobic exercise starts at the point that your body is forced to use glucose from glycogen to provide energy because you have reached the limit of the…

There are two exercise intensity thresholds related to respiration: VT1 and VT2 (ventilatory threshold). Everything from minimal activity far below VT1 to VT2 (a.k.a. "lactate threshold", LT, a.k.a. "anaerobic threshold", AT) is "aerobic". Near the VT2 limit, very little fat is used compared to glucose. Fat burning proportions as high as 95% are only reached under very light activity. (And/or in glycogen depleted exe…

This article has a graph from a lab test:

https://knowledgeiswatt.substack.com/p/20-120-vs-90-gh-of-ca...

I thought it would help illustrate what you're saying but, gosh, those Y axes aren't making things easy to interpret. For those willing to do the mental arithmetic, 1g of FAT is 9 kcal and 1g of CHO is 4 kcal. :)

P.S. It also only starts at 150W.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#147

> Healthy older adults (n = 123, average age 72.0 years, body mass index 25.8 kg/m2) completed three 45-min supervised exercise sessions per week for 6 months. Participants were randomised to treadmill-based moderate-intensity training (n = 45), or high-intensity interval training (n = 41) or a low-intensity active control condition (n = 37), with individualised heart-rate prescription. Dual-energy x-ray absorptiomet…

> "but hiit also causes a lot of damage in a lot of ways"

Please do explain this.

Technically weight lifting (muscle hypertrophy) also causes "damage" but in a controlled an beneficial way.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#148
post #147

> Healthy older adults (n = 123, average age 72.0 years, body mass index 25.8 kg/m2) completed three 45-min supervised exercise sessions per week for 6 months. Participants were randomised to treadmill-based moderate-intensity training (n = 45), or high-intensity interval training (n = 41) or a low-intensity active control condition (n = 37), with individualised heart-rate prescription. Dual-energy x-ray absorptiomet…

> "but hiit also causes a lot of damage in a lot of ways" Please do explain this. Technically weight lifting (muscle hypertrophy) also causes "damage" but in a controlled an beneficial way.

I would guess they mean hiit can traumatize e.g. joints or cardiovascular system, especially for the elderly.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#149
From the Conclusion:

“High-intensity training reduced fat and maintained lean mass in apparently healthy older adults, though changes were small and not clinically meaningful compared with exercise of lower intensity and considering measurement error.”

I didn’t read the whole paper (didn’t see any reason to after seeing this). But the title seems to be contradicted by this conclusion.

Re: Exercise intensity influences body composition in healthy older adults (2025)

#150

... though changes were small and not clinically meaningful compared with exercise of lower intensity and considering measurement error. Why even share this research ?

Exactly. I pointed this out in another comment before seeing yours. They admit they found nothing.
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