Experts say you can alleviate most exercise aches on your own. The exceptions: "If you've experienced a sudden trauma like a fall, or if the pain keeps you up at night or lasts longer than two weeks, you need to see a doctor," says Sabrina M. Strickland, M.D., an orthopedic surgeon who specializes in sports medicine at the Hospital for Special Surgery in New York City. Otherwise, you most likely have a non-serious injury that can be identified and treated by following the guide below.