Were you surprised how quickly/ fast, Tim Duncan, Kevin Garnett, and Kobe Bryant started declining?

These guy have been playing for roughly 15 years! Surprised? No! I can barely last a summer of pick-up basketball games. These guys do it all year round. During the season and off-season. I think you should play 40+ minutes a game over 82 games in the span of 6 months, see how you feel, then cast the first stone.