Burn N Shed, Los Angeles

Bodies leap into the air and then sink back low to the ground again during a JoZ KnowZ bootcamp, which challenges exercisers to a full-body workout. A mix of calisthenics, weights, plyometrics, and kickboxing delivers muscle-building, heart-pumping activity that helps guests lose weight and tone up. Fitness sessions, held indoors and outdoors, require commitment and determination to yield noticeable results and a scale that doesn't groan when you step on it.