This in particular feels really hand wavy: “After weeks of training, they barely burned more energy per day when they were running 40 kilometers per week than before they started to train.”
What does “barely” mean? 40km/week isn’t that much in terms of calorie burn. The 100 calories/mile rule of thumb says this would imply ~350 calories/day. And this article says a woman would have a daily calorie expenditure of 2400 already (seems high, though). So this is only 15%. But anyway, this drops after adaptation seemingly, so does “barely more” mean 50 calories/day? Or does it mean 300? Because those are very different. And to where is the difference attributable? Because someone going from sedentary to trained runner is going to get a lot more efficient at running. “Less energy on inflammation” is really hard to swallow as the primary source of adaptation, especially when this is presented as conjecture.
At some point, there’s just physics. Running a mile isn’t free, benching 100kg isn’t free. These things take work and we can calculate the minimum energy requirement that adaptation can’t escape. Our bodies do not adapt so far that exercise becomes pointless, it only shifts the balance a little (which might be enough to be demotivating for some people, but it’s still relatively minor.) I was under the impression that the total range of metabolic adaptivity for a given person might be on the order of 25%-30% maybe. That might be an over-estimate. I googled a little and found this paper mentioning adaptations of like 8%-15% for severe calorie restriction diets (depending on how RMR is measured).
It’s not that much in terms of calories. It is a lot of physical activity for a modern human in a developed nation.
The real kicker is that an unchecked diet will offset virtually any amount of exercise. An unchecked diet means people will feel hungrier after exercise and thus eat more. It takes a lot of exercise to reach the point that it manages to outrun appetite and bad eating habits. There are a lot of fat people who work physically demanding jobs.
The issue is the uptick in energy burn is unintuitive especially in the world energy dense high-processed food
As an ex once put "you have to run 5 miles to earn a cupcake - totally not worth it!"
We're glad you're here to poke fun at the research of at least two people with PhD's centered on this topic.
> when you start considering the extremes
When you start considering the extremes, you often find that they can't tell you much about the middle ground.
> As the athletes’ ran more and more over weeks or months, their metabolic engines cut back elsewhere to make room for the extra exercise costs
You clearly burn extra calories when exercising, but the thesis of the article is that it doesn't matter in terms of weight loss because your body will adjust to burn the mean level of calories. The obvious exception are athletes whose energy expenditures simply can't be averaged away.
This leads to the conclusion that it's not just exercise that drives weight loss, but diet and exercise (shocking!) that makes a difference, as you have to run at a net loss over the day.
Most people who want to lose weight (aka mostly unfit/untrained) are not going to be able to exercise the amount would take to truly force a calorie deficit.
This is well known and true even if the claims made better happened to be entirely false. I’m not dismissing your point, here. I agree fully.
Exercise just doesn’t burn enough calories to really matter. Especially in the face of a poor diet. Running burns ~100 calories per mile (yes, varying based on weight and a little bit based on speed but it’s a close enough rule). A can of soda has ~150 calories. There’s just no competition. Someone trying to lose weight can skip a soda or a candy bar and it’s more effective than running an extra mile.
I think you are missing the fundamental part of the article about the calorie expenditures being adjusted based on non-fat body mass.
So, yes Michael Phelps eats a lot of calories, but him (and other pro athletes) have spent their lives building muscle and keeping fat reserves down. Michael Phelps I think is at a 5% body fat, while the average American is 18%+. He needs more calories for that extra body mass that most people the same height don't have.
No way. 5% is well below optimal for athletic performance. At 5% you’re looking at developing health problems. This is the range bodybuilders aim for on stage because they care about looking shredded more than they care about having joints that work.
Phelps was reportedly 8% when he won all those medals in Beijing.
Exercise obviously must burn calories because work is being done. The body can’t overcome physics.
The nuance, and the surprising thing, is that other parts of the body seem to adjust their energy levels to compensate. If you don’t do a lot of exercise, something else burns calories. If you do exercise, the “something else” burns less.
What is the something else? That’s the mystery that still needs to be solved. And by extension, what are the limits of the something else? After all, there are well-documented examples of extreme athletes who consume lots of calories without gaining mass.
The wild thing is he’s saying that’s not true either. He’s saying you never burned the extra calories in the first place.