Athletes tend to not think too much on their calves, aside from how awesome the muscle group looks when finely toned. However, it may be easily ignored, but it is one of the most important muscles in the leg, and when you injure it, the calf won't let you forget it. Formed from the combination of the soleus and the gastrocnemius muscles, straining these muscles is one of the most common sports injuries for athletes, and athletes are at risk each time they push off. When stretched beyond capacity, the muscle fibers tear away from the tendon, creating a nagging paint hat will keep you down. With three grades of severity, calf strain can range from mild tears and symptoms to a complete rupture that may require surgery.