The Throwing Chain is a great tool to provide sport specific exercises to develop strength and flexibility. It is an ideal training instrument for enhancing power, balance, stability, and endurance. This unique device is ideal for high intensity low duration exercises and allows the prerequisite range of motion necessary to develop arm speed resulting in increased velocity. It is used in many throwing sports to develop explosive arm action. The variable resistance provided by the chain allow for sport specific movements, preparing muscles used for throwing and getting maximum transfer from training to competition. The Thowing Speed Chain - Pro is typically used by collegiate and professional pitchers. Muscularly mature athletes (including those considered strong for their age group) should consider using a heavier Throwing Chain. Athletes taller than 6'4" should add extensions to this product. Chain ends should never be allowed to come off the ground/floor or gather around the feet during exercises.