For reference, I am 5'3" 150lbs and I got a medium.These are great! They are very lightweight and the polyester/nylon blend feels like it will be moisture-wicking (I've yet to put these to the test, but I certainly will!). The pants have a zipper on the ankles, so you can unzip them for a flared-pants look, or keep them zipped for a slimmer look. They have great stretch too and I feel no constraint doing anything. Stretching? Check. Running? Check. Jumping? Check! Cartwheeling? Check, check, cheSee full review