The new UNLV gym is 100x better then the old gym. It contains two pools, two raquetball courts, multiple basketball courts, a large cardio room and large weight room with both machines and free weights. Personally, I like going here better then my local 24-Hour Fitness.
If your not part of the UNLV faculty/staff or a student, you can purchase a membership to enjoy all the benefits of the gym as if you were.