Wiktionary (0.00 / 0 votes) Rate this definition: fartlek (Noun) An athletic training technique, used especially in running, in which periods of intense effort alternate with periods of less strenuous effort in a continuous workout.
Knee Problems and Injuries - Check Your Symptoms. Knee Problems and Injuries. Knee Problems and Injuries. Knee Problems and Injuries. Call 911 if a bone is poking through the skin. The hurt limb or joint looks odd, is a strange shape, or is out of its normal position. The skin over the site of an injury is broken. You have signs of nerve or blood vessel damage, such as: Numbness, tingling, or a pins-and-needles feeling.
Symptoms of a severe and sudden (acute) anterior cruciate ligament (ACL) injury include: 1  Feeling or hearing a pop in the knee at the time of injury. 2  Sudden instability in the knee. 3  Pain on the outside and back of the knee.  Knee swelling within the first few hours of the 1  injury. Limited knee movement because of swelling and/or pain.