If something hurts when you move and you don't know what's causing the pain, you may need to see a health care professional who practices kinesiology, which is the study of movement, most often applied to humans.
One of the most well-known kinesiologists in America is Dr. Jim Walker. Walker's degrees are in sports physiology and movement biomechanics, the essence of kinesiology. He works at a specialty clinic called TOSH, or The Orthopedic Specialty Hospital, in Murray, Utah. TOSH is also nationally famous, especially among athletes and orthopedic surgeons.
"We have force plates and the force treadmill that we use to assess movements," Walker explains. "With that, and our motion capture system, we can actually measure the forces of movement, including joint velocity. We can assess any movement the person or patient wants to have assessed. We can examine the strength or weakness between one joint and the same joint on the other side, or the way the hip is working in relation to the knee. Any type of movement can be analyzed."
Walker believes that any athlete who has suffered an injury should have a movement assessment after healing to see if the injured part is restored to full function and not being "favored."
"If you don't move correctly after an injury," he says, "it puts forces into another body part to make up for the incorrect movement. For example, if a part on one side of the body is doing more work than the same part on the other side, it puts more forces on that side of the body. So you will essentially wear that side of the body out quicker than you would if you were sharing forces equally, or you may redistribute forces to other parts of your body."
Injuries most often happen when an athlete makes repetitive movements as part of their sport. For example, a swimmer would suffer a shoulder injury. There are even names for some of these common injuries. For example, a tennis player gets "tennis elbow." "Golfer's back" is a pain from the twisting motion of golf.
Any repetitive movement done over and over again may result in injury. Often such an injury comes from the athlete not having totally proper form. That's why technique, even for recreational athletes, is extremely important.
Any joint overloaded in a sport may eventually give out. This does not include "contact" injuries that come from a fall, like endoing (end-over-end-over end) on your mountain bike, where the rider hurts the chin, elbow or other body parts.
Many sports, such as soccer and skiing, involve ripping or tearing injuries of the ACL (anterior cruciate ligament) that holds the front of the knee in place. It happens when the larger lower leg bone, the tibia, slides in front of the femur.
There are four ligaments that hold the knee together in front (ACL), back (PCL, or posterior cruciate ligament) and on either side. The MCL, or medial collateral ligament, is on the inside of the knee, the lateral collateral ligament (LCL) on the outside.
To help prevent a torn or sprained knee ligament, the tendons of the leg muscles such as the quadriceps and hamstrings must be strengthened. This is a big reason for doing weighted squats, which work those tendons plus all four of the knee ligaments.
However, says Walker, "I think ankle sprains are more common than knee injuries. The ankle has a lot of 'white tissue,' tendons and ligaments, and is thus more easily sprained. But there is a way to stabilize the ankle so it is less likely to be sprained. You lay on your back, raise one leg, and write the alphabet with your foot."
He goes on to explain that moving the ankle in so many directions teaches how to activate and move the muscles around the ankle, so if someone gets into an unstable position, he or she will know how to use those muscles to regain balance. And balance, in life as well as sport, is the saving grace of the game.