Likewise, it's hard to add anything to what has already been said except that improvement is inevitable if he continues to ride. Being over 50 is irrelevant to improving condition.
I was in the best cycling shape of my life all though my 30s and early 40s. I sort of let myself go for awhile but have enjoyed a renaissance in my 50s (I'm 54) and would guess that I could kick my 45 year old rear end if it was possible to try.
-Dennis