The human body will always revert back to physical type. The human body prefers remaining at the status quo of their physical type. Most of the jocks in the pictures give a good example. Yeah, know some BB'er have problems chewing gum and walking at the same time. But you could include BB'ing as a athletic undertaking to a lesser degree.
The accepted main human type are Ectomorph, Endomorph or Mesomorph. There are rarely a perfect fit exclusively into one distinct body type at 100%. When taking time off from training, most will lose a bit of an edge, either strength or muscle mass, they worked hard to achieve. That's just a given by nature. Though the Mesomorph types will generally hold to most of their gains to a reasonable level. It's that nasty reverting back to natural body type again.
Can honestly say, when most reach the mid 40's, than turn out the lights the party's over....including me. Guy's can certainly keep training and lifting and maybe have some impressive results to show for them at their age, that's their inclination to train. Though there may be exceptions, reaching that peak and PB in younger lifting days may be in the past tense. Have known a couple of guy's (21 and 27 years old) , forced to take a 3 to 5 of months off of training and drop between 30 to 40lbs. The reverting back to physical type again. The body functions best in it's natural state it was born with.
