Every human should be able to do a flat-footed squat
(www.survivalandserenity.com)
Honestly, I already do this. I don't do it for anything crazy heavy, but, 225 for 10 seconds at the bottom is pretty easy for me. As far as I know, I haven't felt any sort of negative affects from it, so maybe it is as well good for you, or I'm just young enough to be able to take it.