Prevention suggestions include warming up before exercise or exertion, using good equipment, and using common sense to keep physical activity within your physical capacities. Injuries can be classified either as acute or chronic. Acute injuries occur suddenly, such as broken bones or sprains. Chronic injuries progress gradually, such as tendinitis and bursitis. Acute injury is apparent through sudden pain, point tenderness, and loss of range of motion; swelling will be noticeable. Chronic conditions can be less obvious. The persistence of pain even after avoiding the aggravating activity for several days usually indicates more than a minor condition. For treatment of acute orthopedic or soft tissue injuries, rest, ice, compression, and elevation should be used. Each of these measures aids in arresting inflammation and speeding the healing process. After the initial 3 days, ice treatments should continue until swelling has peaked or stopped. Continue to apply ice for 20 minutes at a time several times each day. Information on the nature and treatment of common musculoskeletal injuries addresses strains, sprains, shin splints, achilles tendinitis, knee pain, heel spurs, heel bruise, tennis elbow, shoulder pain, back pain, and muscle cramps.