What is a Calf Strain?

A sharp pain in the calf muscle followed by difficulty using it is probably a calf strain. The most common place for this injury is in the muscle, about half way between the knee and the heel.
 

Symptoms 

• A sudden pain at the back of the leg
• If you have trouble contracting the muscle or standing on your tiptoe
• Pain, swelling, or bruising in the calf muscle