A hamstring injury is a condition resulting from tearing or other damage to the muscles and associated fibres at the back of the upper leg. There are different grades of injury ranging from grade 1 (sensation of cramp or tightness) to grade 3 (tearing of the muscle). These injuries are commonly experienced by athletes across a broad range of injuries, but are especially prevalent in track and field athletes like sprinters. Predisposing factors include muscle weakness or imbalance, poor flexibility, fatigue and poor running technique. Additionally, those who have previously experienced such an injury are particularly liable to experience one again. Thigh compression sleeves like the ones below can be of help in reducing the risk of these injuries.