Tennis Resistance Bands 40″ can be used to improve a players strength, agility, and stability. The Lite Resistance Bands allow for a greater range of motion while targeting the shoulder muscles included rotater cuff strengthening. The bands which increases in tensile strength as they get thicker allow you to target all areas of the body for functional fitness training, dynamic warm-ups and balance training. Use the thicker Power Resistance bands for lower body strengthening and stretching.