General Knowledge..

Straining of the hamstring, also known as a pulled hamstring, is defined as an excessive stretch or tear of muscle fibers and related tissues.

Grade I
With a grade one hamstring strain the signs may not be present until after the activity is over. There may be a sensation of cramp or tightness and a slight feeling of pain when the muscles are stretched or contracted. It also may be referred to as a "pulled hammy".

Grade II
With a grade two hamstring strain there is immediate pain which is more severe than the pain of a grade one injury. It is confirmed by pain on stretch and contraction of the muscle. A grade two hamstring strain is usually sore to touch.

Grade III
A grade three hamstring strain is a catastrophic injury. There is an immediate burning or stabbing pain and the athlete is unable to walk without pain. The muscle is completely torn and there may be a large lump of muscle tissue above a depression where the tear is. After a few days with grade two and three injuries a large bruise may appear below the injury site caused by the bleeding within the tissues.