Is Obesity A Muscle Problem?

Muscle is where most of the glucose goes, and muscle insulin resistance is the first thing that breaks on the road to type 2 diabetes. Both of those are true, and neither one means that building more muscle is the treatment for obesity. This episode works through what actually decides whether a tissue handles fuel well: not how much of it you have, but how fast it's moving fuel through. We go through the one-legged exercise studies, the 18,000-person analysis of what body composition actually predicts, the athlete's paradox, the energy cost of building a kilogram of muscle, the GLP-1 lean mass panic, and why sarcopenic obesity is named after the wrong organ.

This is part two of a two-part series on storage capacity. Part one covered where body fat goes and what happens when the storage runs out.

Timestamps

0:00   The one-leg study, and the muscle-centric claim02:06   What obesity is, and the garage analogy05:06   How glucose gets into a muscle cell11:21   Insulin sensitivity improves without building muscle17:11   The best case for muscle-centric medicine21:13   What predicts falls and death: strength, not lean mass25:18   Separating muscle size from muscle function31:33   Liver fat: amount, type, and flux37:54   Should you build muscle first? The arithmetic42:37   Building muscle in a calorie deficit50:29   GLP-1s, DXA, and the lean mass panic58:23   Sarcopenic obesity, and why the name is wrong01:04:37 Why size still tells you something01:11:46 So what is obesity?

Resources:

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3.   Bhasin S, Travison TG, Manini TM, et al. Sarcopenia definition: the position statements of the Sarcopenia Definition and Outcomes Consortium. J Am Geriatr Soc. 2020;68(7):1410-1418. doi:10.1111/jgs.16372. PMID: 32150289. https://doi.org/10.1111/jgs.16372

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