Originally Posted by Brian Ratliff

Along these lines, I think there is a mental aspect to it as well. When I was a teenager, I very much doubt that swim practice hurt any less than if I were still participating now. But when I was a teen, I didn't think of the pain, I thought about the results and the pain was incidental. Now, even though I am not out of my 20's yet (though close) I find myself fearing the pain more now. It has a cyclical effect because, the more I fear the pain, the less I ride (I ride more than I swim now) and the less I ride, the more it hurts to train.

There is truth to the expression "to let oneself go". You give up, and when you give up, it becomes harder to get back to your previous level. So what's the solution to less fitness as you age? You don't "let yourself go". If you do it becomes that much harder to get yourself back.