My wife and I have a motto: You can't help getting older, but you can stay immature!

Exercise in general (hiking for both of us, running for my wife) definitely makes you feel younger. Biking, my body may not push the bike as fast as it once did but I'm able to ride longer at higher average speeds than I did 30 years ago - mainly through learning how to get in cycling shape and better eating/drinking habits on the bike.