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Comment by carlsborg | Hacker News Reader

The Mifflin-St Jeor equation equation for working out Base Metabolic Rate, as stated in this post, is for males. The original subtracts a different constant for females (-161 instead of -5). It is a 1990 paper. And it subtracts these arbitrary constants independent of the other variables, makes me think its limited in its usefulness.

I believe that weight training, maybe even cardio, increases this BMR for many hours after the workout, so I dont agree with the "not a major contributor to losing weight" argument if its done regularly.

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I think it's probably based off the empirical observation that in studies of free-living individuals, moderate increases in exercise output simply don't result in weight loss.

The thinking is that our bodies are very good at recognizing a calorie deficit and respond very effectively by increasing spontaneous intake to balance the calorie budget. It often only takes very small increases in intake -- so low they can easily go unnoticed (or that people deny they could have happened, again why metabolic ward studies are so vital) -- to obliterate the calorie expenditure of moderate exercise.

yeah, it's a bit strange. generally, most papers say exercise isn't a huge contributor but at least in my case it makes all the difference. theoretically muscle mass burns few additional calories (see https://www.strongerbyscience.com/calories-muscle-burn/) and you have to a lot of cardio to significantly push the envelope.

as soon as i start weight training 3 times a week or endurance training 5 times a week (i'm bad at combining the two) i have to up my intake significantly just to keep my weight at the same level and gaining often means eating more than i'm comfortable with (considering my dietary preferences).

https://pubmed.ncbi.nlm.nih.gov/17101527/

How does the paper you posted, about post exercise oxygen consumption, relate to weight loss as we have been discussing here? I don't mean this to be flippant, I just don't have time to do a deep dive on this paper and you didn't provide any context.

Reading the abstract is always a good start! ;PPPP

"A number of investigators in the first half of the last century reported prolonged EPOC durations and that the EPOC was a major component of the thermic effect of activity. It was therefore thought that the EPOC was a major contributor to total daily energy expenditure and hence the maintenance of body mass. Investigations conducted over the last two or three decades have improved the experimental protocols used in the pioneering studies and therefore have more accurately characterized the EPOC. Evidence has accumulated to suggest an exponential relationship between exercise intensity and the magnitude of the EPOC for specific exercise durations.

...

Notwithstanding the aforementioned, the earlier research optimism regarding an important role for the EPOC in weight loss is generally unfounded. This is further reinforced by acknowledging that the exercise stimuli required to promote a prolonged EPOC are unlikely to be tolerated by non-athletic individuals. The role of exercise in the maintenance of body mass is therefore predominantly mediated via the cumulative effect of the energy expenditure during the actual exercise."

Here's a experiment from 2011, five years after that paper (in fact it cites it), N=22 and using a metabolic chamber:

"A 45-Minute Vigorous Exercise Bout Increases Metabolic Rate for 14 Hours"

https://www.academia.edu/download/45878998/A_45-Minute_Vigor...

where they conclude ".. vigorous exercise for 45 min resulted in a significant elevation in postexercise energy expenditure that persisted for 14 h. The 190 kcal expended after exercise above resting levels represented an additional 37% to the net energy expended during the 45-min cycling bout"

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