Exercising is good for you, but sometimes you can injure yourself when you play sports or exercise. Accidents, poor training practices, or improper gear can cause them. Some people get hurt because they are not in shape. Not warming up or stretching enough can also lead to injuries.
The most common sports injuries are
Sprains and strains
Knee injuries
Swollen muscles
Achilles tendon injuries
Pain along the shin bone
Rotator cuff injuries
Fractures (broken bones)
Dislocations
If you get hurt, stop playing. Continuing to play or exercise can cause more harm. Treatment often begins with the RICE (Rest, Ice, Compression, and Elevation) method to relieve pain, reduce swelling, and speed healing. Other possible treatments include pain relievers, keeping the injured area from moving, rehabilitation, and sometimes surgery.
NIH: National Institute of Arthritis and Musculoskeletal and Skin Diseases