This review is only for the fitness area. I did not go to or use any of the spa services.
Canyon Ranch has absolutely the nicest fitness areas out of any hotel I've been to. Then again, it is Vegas so you expect them to go big with everything they do.
The gym itself has all the important machines and they're all high quality. They aren't the cheap light ones that have fraying cables or anything. They've got quality equipment and a decent amount of free weights that you can use. They have a squat rack and barbell bench seat too so you're set on your 5x5s. The cardio are has around 20 treadmills and a few stair climbers. There's a "core" room for stretching and/or core exercises. They've got a yoga room and an indoor rock climbing facility too.