Deep (aka past-parallel) squats sound downright scary — won’t the pressure hurt knees? What about backs? But with the right preparation and flexibility, past-90-degree squats can burn more calories, use more muscles, and build a better booty than squatting parallel. Take time to chat with a trainer or physical therapist before getting started (especially if you have a history of joint problems), since this exercise can do more harm than good if done improperly.

Gold Star Squat:

Just getting started? Learn all about squats here.

Loosey Goosey:

Relax tight leg muscles with one of these awesome recovery tools.