Well... I like every sport existing (minus golf, which I consider utterly boring), but my favorite one, of all times, and of all ages is: swimming
It's a complete sport: great for every single muscle you could think of (including the heart), and it's extremely healthy.
I practice it because, besides its fun, I love water and I also got terrible back aches, so it helpes a lot there.
I swim since I was 5-6 years old.
The other sport I practice (since april 2005) is tennis. Also great fun, and very healthy.
I like playing voley ball and football (when my pals allow me to), and I used to play handball too.
So... that would be it. Keep sporting
Namarie!