RosinBag pinned it on relaxing. I started swimming again about a month ago to train for a sprint tri in May. I don't think I had swam in a pool since high school and after a couple of laps I thought I was going to drown. Once I remembered to relax and have fun, it went much better. It's been a great addition to the workout routine. Like Becca said it's a totally different feeling, and hitting the hot tub after is a nice bonus.