In order to increase fitness and cardiovascular endurance I've added swimming to my routine. I'm taking lessons at the Y because I didn't learn the stroke mechanics when I was younger. I've switched to swim briefs for my lap swimming. I've already cut down my weight by about 15 lb and most likely will drop additional lbs as swimming seems to be successful. I've had a little trouble finding the type of fit I want. At first I ordered one size up from my current waist which is 36 inches. About 4 months ago I had a 38 inch waist. The first one I ordered was XXL which had too much stretch all around the waist. I returned it and ordered an XL which is just the athletic fit I needed. It's very snug . The front fits like a well fitted athletic supporter and the back locks over my glutes. When I wore it for some laps ,it was just right. My older swim brief was getting too loose with water getting into both front and back plus the brief was feeling like it wasn't snug enough. If you get the correct size. You can't go wrong. You'll tell yourself you found a great fit