I'm not sure we're fitter now than we were a decade ago. When I go to the gym I'd guess the average age in there is 30ish. My last Stn Cdr's sports day I decided to run a leg of the 4x100 relay and thought I was in for a thrashing as I was 36.....looking across the lanes it turned out I was one of the younger runners! Asking where the SAC/Cpl/Fg Offs were someone replied "on their f*kng playstations".