I'm not sure how expensive whole body air displacement is in the civilian world, but it seems like a decent way to measure lean mass.
I would guess that 3D scanning is the better way. In principle a smart phone app should be able to do this sooner or later by using camera + accelerometer.
The most recent post in December's Stupid Questions article is from the 11th.
I suppose as the article's been pushed further down the list of new articles, it's had less exposure, so here's another one for the rest of December.
Plus I have a few questions, so I'll get it kicked off.
It was said in the last one, and it's good advice, I think:
This thread is for asking any questions that might seem obvious, tangential, silly or what-have-you. Don't be shy, everyone has holes in their knowledge, though the fewer and the smaller we can make them, the better.
Please be respectful of other people's admitting ignorance and don't mock them for it, as they're doing a noble thing.