For instance, there are two types of tennis balls. The first is pressurized while the other one doesn t. The pressurized version has a hollow core and is filled with air. This is the kind used in major tournaments and has to be disposed off afterwards because it will no longer bounce that well after less than a month in use. The game was still called La Soule where players used their hands or a stick to hit the ball. La Soule soon became a popular ball game outside of the monasteries. Later on, around the 12th and 13th centuries, the game was further developed. Instead of just using the hand, players created a leather glove so that they could take more control when hitting the ball with their hands. When you are like Carrie Bradshaw of Sex and the City, you take any pair of shoes that you fancy off the rack, regardless whether it's expensive or killing the blood supply on your biggest toe, as long as it looks good on you. But when choosing tennis shoes, you have to consider some factors before parting with one from a store. Do the ball toss by releasing the ball slightly in front of the shoulder while the racquet is facing downwards and is terminally retracted. Bend your racquet arm elbow to elevate the racquet while the left arm remains pointing at the ball. 4. While the ball is at its highest point, prepare for a throwing position by dropping your racquet and keeping your elbow high. Another important factor to consider aside from the materials is the types of feet and the kinds of shoes that go well with them. There are 3 types of feet: pronated, supinated and neutral. Feet that are pronated have arches that are low. They walk or run with the heels first ending with the toe. These have greater tendencies to fall over so the shoes that fit them are the ones that resist falling over. It is the first senior play-offs among nations that bring together a great number of retired prominent professional tennis players from ATP and Davis Matches. Tennis Masters Event as well as Grand Slams and ATP are also being co-hosted and co-owned by ITF, International tennis number (ITN) The International Tennis Number stands for the general category of a player's performance.