Basic facts about tennis racquet strings
Even the best racquet in the world can be rendered virtually unplayable by a poor string job. You should choose your string and tension with at least as much care as you choose your racquet.
Synthetic strings made of nylon and polyester often last a long time, but virtually all of them go “dead” after about a month, whether or not you play. Just because the string isn’t broken doesn’t mean it’s still good. Natural gut, while initially more expensive and somewhat more fragile, is good almost up to the moment it breaks.
When strings go “dead,” they don’t lose power, they lose tension. This means that you have looser strings, so the ball goes farther for the same effort, with less control. You also lose control because the strings feel differently than they do when they're fresh, so you either have to adjust your game, or content yourself with not playing your best.
The “rule of thumb” is that you should re-string your racquet(s) as many times per year as you play per week (unless your strings break, of course). Unless you are using natural gut, this is not nearly often enough. I think you should aim to re-string every month. That way, your racquet is always playing its best, and you won’t have to adjust your game nearly as much, to compensate for the difference in feel between dead strings and fresh strings. If once a month sounds too often for the amount of tennis you play, play more tennis!
- Lower string tensions generate more power.
- Higher string tensions allow for more ball control (for experienced players).
- A longer string (or string plane area) produces more power.
- Decreased string density (fewer strings) generates more power.
- Thinner string generates more power.
- More elastic strings generate more power.
- Strings that produce more power will also absorb more shock load at impact.
- Softer strings, or strings with a softer coating, tend to vibrate less.
- A stiffer stringbed tends to produce more spin.
- The more elastic the string, the more tension loss in the racquet after the string job.*
* Pre-stretching aligns (stretches) the polymer chains in the string and “sets” the string, which reduces tension loss, albeit slightly. The more pre-stretching (prior to stringing) the less tension loss after stringing, but the less lively the string will be, even when new.