Cramps in the legs and back may be more serious.

Cramps in the legs and low back during exercise may not be just a benign case of fatigue. These cramps may be a result of exertional rhabdomyolysis, a rare but potentially deadly complication when an athlete with sickle cell trait over exerts. Sickle cell trait is different from sickle cell disease in the fact that the athlete only carries one gene of sickle cell hemoglobin and instead of the two that result in disease. They also have one gene for normal hemoglobin. During intense exercise (especially without proper hydration) the sickle hemoglobin may change the shape of the red blood cell causing it to sickle and decreasing its ability to transport oxygen. Without oxygen during exercise exertional rhabdomyolysis may result. Since cardiac muscle has some skeletal muscle properties, this muscle breakdown will affect the heart as well as the skeletal muscles (mainly legs and back). According to the Columbia Tribune (Missouri), 7 of the 19 non-traumatic NCAA football deaths have been attributed to complications of the sickle cell trait. There has been enough concern, that the NCAA has recommended testing for the sickle cell trait in their pre-participation physicals. With dehydration being a complicating factor with the sickle cell trait, it may be a good idea for testing for this condition be apart of interscholastic sport as well as collegiate. National Athletic Trainers' Association (NATA) Consensus Statement.