One of the reasons I created my website http://meetandplay.com/ as after high school I stopped being active, gained 60 pounds programming and playing video games. As an adult you have to be really proactive to find sports to play they don't just fall in your lap anymore. meetup.com is also a good resource for healthy people doing healthy stuff like hiking, biking, climbing which I've used as well. My site is more for pick up games and locations to play. :)