Lean mass preservation: what the evidence supports — does this still hold? posts 91–120

Comparison to published data: the trials reported mean fat and lean mass changes. Individual results vary around that mean. Being above or below average is not a sign of something wrong.

The evidence for this is thinner than the way I have phrased it suggests.

Reading back through, this was answered upthread and I missed it. My fault.

I had written a reply contradicting post #103 and deleted it. Here is what survived.

Percentage body fat is a ratio, so it changes when either component changes. A rising percentage during weight loss is arithmetic before it is physiology.

Confirming post #107 from a second method, which matters more than confirming it from a second person.

I changed my mind about Lean mass preservation after someone here asked me for the source and I could not produce one. That is worth saying out loud because it is the ordinary way it happens.

Two things can be true about Lean mass preservation at once: the mechanism is plausible and the evidence for the size of the effect is thin. Most of the argument here is people defending the first against attacks on the second.

Taking post #107 at face value and following it one step further.

Photographs under fixed lighting and posture are a genuine record and are the hardest of these to standardise.

Two people in this thread mean different things by Lean mass preservation and are disagreeing about the definition while believing they are disagreeing about the facts. Worth pausing to define it.

Useful. I had the fact and not the reason, which turns out to be the important half.

Post #111 put the caveat in the right place and I want to underline it.

The version of Lean mass preservation that circulates here is a simplification of a simplification. It is not wrong, but it has lost the conditions under which it holds, and those conditions are where the interesting cases live.

The most useful protocol is the one you will actually repeat identically. An imperfect measurement repeated consistently beats a better one repeated carelessly.

Adding a reference point for Lean mass preservation. Mine is a single case, collected without controls, and I am posting the method alongside it so it can be discounted appropriately.

The failure mode on Lean mass preservation is boring rather than dramatic. It is almost always the step everyone assumes was done correctly because it is too simple to get wrong.

Where I part company with post #116, and it is a narrow parting.

Neither method is capable of detecting the month-to-month changes that people report detecting month to month.

The rule of thumb is fine; the edge cases are where it earns its keep.

Picking up post #118: that is the part I would want checked first.

Lean mass preservation is a question about a distribution, not about a value, and treating it as a value is what produces the confident wrong answers.

That is clearer than the version I had in my head. Thank you.