### Instruction:
What is the best string tension for a tennis racket?

### Response:
The best string tension for a tennis racket will depend on the racket, the type of strings, and the player. Generally speaking, a higher tension will offer more control, while a lower tension will offer more power. Strings such as polyester, which are common among intermediate and advanced players, are stiffer and usually play better at a lower tension, around 50 lbs or 22 kg. Strings like synthetic gut, which are common among beginners and juniors, play better at 55 lbs or more. This will vary based on the racket, which can also offer more of its own power or control.