Once upon a time, there was a boy who loved to play sports. In fact, as a boy, he played every sport he possibly could. As a youth, he played four sports. When he moved into middle school and high school, he dropped down to three. By the end of high school, he played two. In college, one. By the time this man finished college, he no longer played sports.
As life and responsibilities piled up, the man grew more and more depressed. He couldn’t figure out why. He had straight As, plenty of friends, a nice apartment, a wonderful wife, and a child on the way. He even had Jesus. But something was missing.
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Then one day, this man hopped on a bike. He peddled hard and he peddled far. Far, far away. When he finally returned home, he realized what he had been missing. And the man lived happily ever after.
Omer Redden 
I would most definately have to agree that this is a key habit for the good life. The boy you were describing could describe me to a tee. I had played sports my whole life and quit basketball after my freshmen year of college and did nothing competitively since then. Now I’m back to playing several times a week for fun. I feel better and have been much much happier. Good bit of advice to live the happy life.