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 claim
• 02:06 What obesity is, and the garage analogy
• 05:06 How glucose gets into a muscle cell
• 11:21 Insulin sensitivity improves without building muscle
• 17:11 The best case for muscle-centric medicine
• 21:13 What predicts falls and death: strength, not lean mass
• 25:18 Separating muscle size from muscle function
• 31:33 Liver fat: amount, type, and flux
• 37:54 Should you build muscle first? The arithmetic
• 42:37 Building muscle in a calorie deficit
• 50:29 GLP-1s, DXA, and the lean mass panic
• 58:23 Sarcopenic obesity, and why the name is wrong
• 01:04:37 Why size still tells you something
• 01:11:46 So what is obesity?

Resources:

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