Resistance tube training is one of the most effective forms of exercise for performing lower body, upper body, and core conditioning. Whether your goal is building lean muscle mass or shedding excess body fat, the Zon Extra Heavy Resistance Tube will help you reach your goals. Use the tube to burn fat through high-rep, low-resistance exercises, or to gain lean muscle mass through low-rep, high-resistance exercises. Isolate individual muscles or use as a full range of motion exerciser. Resistance tube training is a safe, proven, do-anywhere routine to build strength and improve tone; no bulky metal weights needed.