54 here, it's just a number. Still do everything I did when I was twenty except contact sports! Still motorcycle, but did get rid of my modded Kawasaki ZX-14 and got a Suzuki Bandit 1250S, which is now modded as well. Still bicycle long distances. Was in Spain this year and hiked for 2 weeks on the Camino! Going back next spring to finish. About a half marathon a day with a back pack in mountainous country. Point is if you look after yourself, it really is just a number. My dad will be 89 in a few weeks and still does pretty much everything. One thing I can guarantee, no one can skip 'old', but make sure you treat your body at least as good as you treat your car! I laugh when at bike night guys will argue about how often to change your oil to insure maximum engine life and they are over weight and smoke!