Comment by bitexploder
6 hours ago
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 present for both groups.
> The fat loss is simple energy expenditure.
But it's not, unless there is a calorie deficit.
If you do aerobic exercise, almost all the energy comes from burning fat. Because your body will have used very little glucose, you're unlikely to feel particularly hungry after that exercise.
If you do anaerobic exercise, almost all the energy comes from glycogen stores. Your body will crave carbohydrates immediately after exercise, and only resort to glucogenesis burning fat if you don't fuel enough afterwards.
There's a significantly higher risk of over-consumption after doing anerobic exercise and aerobic exercise because your body wants to replace the glycogen that got used up.
"If you do aerobic exercise, almost all the energy comes from burning fat. " This is directionally incorrect. Your body will burn both concurrently. For low intensity aerobic exercise, fat is used as the dominant energy source. However even at moderate intensity levels like jogging and "zone 2" aerobic you are 50/50. At higher intensity you have crossed the inflection point and are using more glycogen than not. All strictly aerobic exercise. And it all works on a balance anyway. You use glycogen, it gets replaced until everything is topped off. Doing that means it isn't getting converted to fat.
Both forms of exercise are shown to have an "anti-hunger" effect.
And unless you are walking, your body is also shunting blood away from your gut which also has a secondary hunger dampening effect as it doesn't resume blood flow too it immediately.
So for anything we would call aerobic exercise, that is zone 2 "cardio" or greater, I would have to disagree with your main claims about it.
> 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 energy your body can produce from burning fat, because your body can't provide oxygen at the rate required to do so.
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Can you clarify your last paragraph, looks like there’s a typo or grammatical error that states the same outcome for both arguments put forward in the preceding paragraphs.
I can't edit it now as it was posted more than 2 hours ago, but good spot.
"anerobic exercise and aerobic exercise" should have read "anerobic exercise compared to anaerobic exercise".
some people may become experience increased appetite from workout while others may have hunger dampening effect.
but bigger reason imho is that people overestimate calorie burn from exercises and fool themselves into thinking now it's OK to consume more food.
I would have thought the fat loss comes from hormonal changes, not merely the energy used during exercise.