The Men's Flex Short by Prana. Flex Short: If you're like us, your best days involve several different sports. We built this short with recycled polyester and a bit of spandex for mobility, and added a Coolmax short style liner and a side stash pocket.
"Good pair of shorts where unrestricted motion is a must"
Picked up this pair of shorts for yoga. I purchased a medium (normally wear 33-34 waist, 5'11") and the fit is slim but not tight. The material has plenty of stretch. The inner lining is breathable and more of a boxer briefs cut. Small pocket on the side with Velcro closure is small but enough to fit an iPhone and keys. The pocket has a tall flap making it it's contents secure while you're at the gym but as a result not the easiest pocket to retrieve items from. It's also in front enough that it's contents won't bother you while sitting. Overall, an intelligently designed pair of shorts by Prana.
I now own three pair of these shorts after buying my first pair on points this spring. They are hands down the best gym short I have found. Fabric is flexible with out looking like a pair of bike shorts, and the liner keeps the boys from being exposed while being comfortable. The price tag while make you think twice, but wear them for a workout and you will never regret it. The side pocket just fits a my cell phone which is a Galaxy S3.
Hands down my favorite shorts that I own. The liner in them is very comfortable and the length is long enough that you don't expose the boys when hitting the bench at the gym. I have even started wearing them on days that I just run. If you like to carry more then a gel pack or a cell phone then they probably are not going to be your top choice. All that said they are still the shorts that I grab when doing anything athletic.