I recently listened to a podcast (and subsequently read the discussed paper) where Dr. Herman Pontzer discussed his research on contemporary hunter-gatherers and found that despite a multiple-fold discrepancy in activity levels between H-G groups and contemporary Western populations, total energy expenditure leveled off at higher levels of activity. He and his team even argue that the discrepancy in activity energy expenditure (on the order of 500/600 calories) cannot be fully explained away by changes in NEAT, since their study design included accelerometry to account for this.
While I was listening, I was reminded of the excellent article Dr. Baraki posted on the blog a while back on NEAT being a primary driver of weight-loss plateaus, as part of the neuroendocrine response to prolonged hypocaloric environments.
My question is, does this current research on “Constrained Total Energy Expenditure” make a compelling case to you all for potentially changing management, or generating new theories on metabolic adaptations to training/nutrition?
I completely understand that you all’s time is precious, and that this might not be worth discussing. Thought I’d ask anyway if you all were interested.
Not really. There are multiple inputs to weight loss plateaus, though NEAT is certainly a big player. I wouldn’t say that activity is nearly as big of a driver in weight loss anyway (directly), but the data on it combined with dietary interventions long term do tend to show better outcomes and less recidivism.
It is also well known that energy expenditure secondary to activity is dynamic even if the task is the same. There was another study where women trained for and completed a marathon over 18 months and actually gained fat mass (and some LBM) during the process while they were expected to lose weight given the extra physical activity.
Sh*t is nuanced indeed! A few follow-up questions, if time permits:
Would you argue that the greater long-term success in combined exercise and nutrition interventions vs. diet/exercise alone has more to do with promoting wholesale lifestyle change (i.e. sustainability) as opposed to unique physiologic/metabolic benefits in the short-term?
Do you think exercise and exercise selection play an important role in mobilizing fat tissue during weight loss?
Also, I imagine in that study of women training for a marathon (fascinating), the caloric environment was not regulated meaningfully?
Yea the women were free-living, which is more “real world”, but more confounders for sure.
As far as exercise selection, I don’t really think it’s important for its affect on fat loss (to the extent it does to begin with).
For long term success, yes I think that there is evidence that long term successful dieters tend to exercise much more than those who don’t. I think this represents a fairly significant change in their environment, psychology, and physiology.