My youngest daughter, who just turned 13, is a competitive swimmer, during her winter season she swims about 6-8 hours a week and during the summer it's probably a little more.  She ended her season on February 23 this year.  The other day she was telling me about a fitness test she had to do during gym, and said "it was tough!  Boy, I need to get back in the pool".  I had to laugh.  To be a kid again!  I am exercising more and more, but I can't say that I would miss it as much as she does!  I take kickboxing classes through my work twice a week and I do love it - I've also been using my treadmill, and doing an exercise DVD.  I'll be excited when school ends for me in May and I can devote more time to getting fit.  Get out and get it done everyone!