The Fitness-Mad Power Resistance Loop – Light – brings you a flexible way to strengthen those muscles and train that core. Allowing you to add resistance without adding additional weights, this handy training tool can be used on its own for a wide range of strength training exercises to strengthen muscles and for core conditioning. In addition, you can team it with fitness apparatus or equipment thanks to its heavy-duty latex construction. It is also suitable for rehabilitation. Use anywhere – portable and lightweight, you can sling it in your gym bag or over your shoulder with ease. Light Resistance Loop.