What is jumpers knee?

The patella tendon (or ligament as it is sometimes called) connects the kneecap to tibia bone. Under extreme stresses such as those involved in jumping a partial rupture can occur. This can often lead to inflammation and degeneration of the tissue. Inflammation can also result from overuse. Injury to this often affects athletes involved in jumping or throwing sports. Weight lifters, Tennis and Badminton players can also be affected. Rest in the early stages is important.

Source Badminton Extreme

A bursa is a small sack of fluid that lubricates where tendons move in joints. If the bursa is subjected to repeated trauma then it can become inflamed and swollen causing pain in the wrist. This can affect people who put weight on their hands a lot e.g. cyclists.

Source Badminton Extreme

Tight Calf Muscles
(Gastrocnemius and Soleus)

A common problem in athletes is tight calf muscles, especially in runners. The symptoms are a gradual tightening in the calf muscles which can get worse when running or improve while running only to tighten up later.

Tiny micro tears in the muscles cause them to go into spasm. When they are in spasm or contracted then blood cannot easily get into them. The muscles have squeezed the blood out like a sponge. If the muscles do not get enough blood then they will not get enough nutrients and so will tighten up to protect themselves and weaken and so on.

Source Badminton Extreme

What is tennis elbow or lateral epicondylitis?

Tennis elbow is a common injury and got its' name because tennis players tended to get it. Tennis elbow is inflammation or degeneration of the tendon of the that attaches to the bony bit (lateral epicondyle) on the outside of the arm or elbow. The main tendon involved is that of the extensor carpi radialis brevis muscle. Although the injury is called tendinitis (inflammation of the tendon) a more common occurance is thought to be tendinosis (degeneration of the tendon).
Source Badminton Extreme

What is Scoliosis?

Scoliosis is a sideways curving of the spine that can often result in an 'S' shape or 'C' shape in the spine. If someone runs there fingers down the spine either side of the vertebrae they will leave two red lines. It is often easier to see the curving of the spine in these red lines. Scoliosis is often a result of an imbalance in the muscles caused by one sided activities such as throwing or racket sports. Children can develop scoliosis through carrying heavy bags on one shoulder all day at school.