You know that friend who used to be a jock and now seems kind of lazy — but annoyingly, all he has to do is exercise for a month to get ready for a triathlon?
Well, new research says there's a reason for that.
Muscles actually have a memory of their former strength — and that memory may last indefinitely, University of Oslo physiologist Kristian Gundersen tells NPR's Audie Cornish. Gundersen's team just released a study that has good news for those of us who used to be fit.



