The Bodylastics Cobblestone massage ball is far superior to the lower quality, hard as a rock, high density balls on the market, the Bodylastics ball is a smart addition to your home gym equipment. As you progress on your journey of physical fitness, rolling will first help you to loosen up and avoid injury from "overdoing" it. As your fitness level increases, using your deep tissue ball will become part of your basic routine, flushing lactic acid from your muscle tissue.Massage Ball: Self myofascial release eliminates muscle knots and tension. Simply lean on the massage ball and use your own body weight and gravity to relieve muscle knots & tension.