Lean mass preservation: what the evidence supports

Lean mass preservation: what the evidence supports Writing it up because I had to work it out twice and would rather nobody else did.

Trying to work out what would count as evidence on lean mass preservation, before collecting any. This is the part I usually skip and it is the part that makes the rest useful.

If two explanations predict the same observation, observing it does not help. So: what observation would separate them?

Precision versus accuracy: the precision you need depends on what question you are answering. "Am I losing fat?" requires less precision than "Is my lean mass preservation within the expected range?"

Two people can read the same figure differently here and both be reasonable.

Preserving lean tissue during a substantial deficit depends on protein intake and a resistance stimulus, and the evidence for both is reasonably strong.

None of the above is medical advice and I am not qualified to give any.

Lean mass in these measurements includes water, so a change in hydration appears as a change in lean mass.

If it helps: the failure mode here is usually boring rather than dramatic.

Bone mineral density changes with substantial weight loss are measurable and slow, and are one of the better reasons to have a baseline scan.