Depending on the manufacturing process, tennis balls have different playing characteristics. The most important feature is the filling of the ball core. It makes a big difference whether you play with an air-filled or a gas-filled tennis ball.
The pressure and thickness of the rubber core also play a big role. In general, tennis balls can be divided into two categories, pressurized balls and pressureless balls.
Pressurized balls are tennis balls filled with gas (e.g. nitrogen). The gas ensures that there is a high pressure inside the rubber core. This improves the bounce characteristics of the tennis ball. This ball offers you a very good playing feel, which is why it is especially used in competitions.
However, you will have to make sacrifices in terms of durability. Since pressurized balls have a thin rubber core, the gas escapes over time. This leads to a loss of pressure, which reduces the bounce of the ball noticeably.
For this reason pressurized balls are always sold in airtight cans. You can recognise this can by the fact that it hisses when you open it.
With pressureless balls there is air in the core. Unlike the pressurized tenis ball, no additional pressure is added by the machine. Here the two rubber hemispheres are glued together under normal air pressure.
Another difference to the pressurized ball is the thickness of the rubber core. This is much greater with pressureless balls.
The material composition of the rubber core also varies. This is because in pressureless balls, the rubber core alone influences the bouncing behaviour of the balls. Therefore, particularly elastic materials are used for the core.
The biggest advantage of pressureless balls is their long durability. Since they are filled with normal air, no pressure loss can occur. However, the ball feels a little heavier than a pressurized ball when hitting it because of the thick rubber core.
Furthermore, the pressureless ball plays a little slower and does not bounce so high off the ground. If you are a beginner or recreational player, we recommend playing with pressureless balls. They are cheap, durable and above all perfect for tennis training.
For kids there are special tennis balls, so-called “stage” balls. These are intended as practice balls and have a reduced pressure component. Stage balls are therefore particularly soft and gentle on the arms.
Furthermore, these balls have a lower speed and therefore offer the children a higher reaction time. You can recognise stage tennis balls by the two-coloured surface.
There are three pressure levels in total, from stage 1 to stage 3.
Stage 1 tennis balls are 25% less pressure than normal balls. They are marked with a green dot. These balls are perfect for kids who play at an advanced level. They serve to prepare kids for playing with normal tennis balls.
Tennis balls with orange colour belong to stage 2, where the pressure is reduced by 50%. Compared to the stage 1 balls, they are even softer and slower. Stage 2 balls help kids to learn advanced stroke techniques on the court. With these balls kids are usually allowed to play on the midcourt.
For kids who have just started playing tennis, stage 3 balls are the right choice. These balls are 75% pressure reduced and slightly larger than normal tennis balls. You can recognise them by their red colour.
They make it easier for children to start playing the sport and help them learn the basic stroke techniques and movements. With these balls, children train best on small courts.
Tennis balls made of foam are a good addition to the stage 3 balls. They are often used in training with beginners. Foam balls have the lowest speed of all balls. Therefore the reaction time is the highest and therefore the control is the best.
However, the trajectory of these balls is very short. That is why foam balls are more suitable for playing on smaller court.