and the British journal article linked in a post below is somewhat interesting. It looked at a group (albeit relatively small) over 10 years at the Air Force Academy and noted things equalized in some ways after 2 years by some metrics, but other metrics still showed marked differences. It makes sense and I am sure things would ultimately depend on other factors exactly as you note - such as skeletal and muscle structures. Bottom line is I have been following this Penn story (and it isn't the only example out there) and this does not seem like the right approach.