A hamstring strain is an injury to the group of three muscles that run along the back of your thigh, which allows you to bend your leg at the knee. Unfortunately, hamstring strains are both common and painful.

During a hamstring strain, one or more of the muscles gets stretched too far, and might even start to tear. A hamstring strain is likely during exercisethat involves a lot of running and jumping or sudden stopping and starting.

Hamstring strain is also more likely to occur if:

• Warm up and stretching are not done before exercising.
• The muscles in the front of the thigh (the quadriceps) are a lot stronger than the hamstrings.
• A teenage athlete is going through a growth spurt.

Possible symptoms of a hamstring strain are:

• Sudden and severe pain during exercise, along with a snapping or popping feeling
• Pain in the back of the thigh and lower buttock when walking, straightening the leg, or bending over
• Tenderness
• Bruising

Mild to moderate hamstring strains usually heal by themselves. At home treatment may include:

• Resting and avoiding putting weight on the leg as best you can. If the pain is severe, you may need crutches.
• Icing to reduce pain and swelling
• Compression of your leg. Use an elastic bandage around the leg to keep swelling down.
• Elevation of your leg on a pillow when you’re sitting or lying down
• Taking anti-inflammatory medications
• Stretching and strengthening exercises if your doctor recommends them. Strengthening your hamstrings is the best protection against hamstring strain.

In severe cases, surgery will be needed to repair the muscles and reattach them.