shorten to 3 sentences
Although the terms Muscle Sprain and muscle strain are used loosely and have no precise clinical definition, a sprain generally refers to an injury to a ligament — one of the tough, fibrous cords within a joint that connects the bones together — and a strain refers to muscle injury.
Ligaments hold your skeleton together in a normal alignment. They prevent abnormal movements. However, when too much force is applied to a ligament, such as in a fall, the ligaments can be stretched or torn; this injury is called a sprain. A sprain is caused by a ligament being stretched too far. To avoid sprains it is important to stretch and warm-up properly before exercising, wear proper shoes, and not run on uneven or slippery pavement.