Racket String Tension

Most tennis players choose a tennis racquet with great care, but many don't realize that their racquet's stringing may have a more profound effect on their game than their carefully chosen frame.

At a minimum, every tennis player should understand the basic tradeoffs between power and control in relation to string tension. Any decent tennis racquet will have a recommended range of string tensions, for example 58 to 68 pounds. When we talk about low or high tension, it makes sense to confine ourselves within this range, because at extremes below this range, some of the normal correlations break down. String within the recommended range. Exceeding this range can break your frame and will usually void your warranty.

The fundamental rule regarding tennis string tension is to string tight for control and loose for power. To arrive at the right tension through experimentation, raise or lower the tension in 2 pound increments with each restringing.

A tennis ball returns only 55% or so of its impact energy, but strings return more than 90%. When a ball collides with strings, both deform to some extent. The more the strings store the energy of the collision by deforming like a trampoline, the less the ball stores energy by flattening. To get the most energy return out of the collision, we want the strings to store as much of the total energy as possible, because they will give back more than 90% of it, whereas almost half of any energy stored in the ball will be wasted. Looser strings deform more easily, thus storing more of the energy of the collision and minimizing the amount wasted by the ball.

As the looser string bed compresses more, the ball stays on the strings longer, during which time any tiny changes in your racquet position can change the path of the ball. The ball isn't on your strings long enough for you to consciously do anything to it. Your brain can't execute any actions in the few milliseconds available, but that few milliseconds is enough time for unintended movement to occur, especially when an off-center hit exerts a turning force on the racquet head.

When getting your racket strung, check the type of machine. If you have been getting your rackets strung on a spring-type machine, and your new stringer is using a drop weight or continuous pull machine, you should lower your requested tension by 3-6 pounds to accommodate the difference in the pulling mechanisms. Your stringer will advise you on this.

How often should I restring?

The conventional rule of thumb is to restring as often per year as you play per week, but no less often than twice per year. It won't hurt your racquet to restring less often, but your strings might lose their responsiveness.

What's the best tension?

Generally, tighter strings offer more control, looser strings more comfort. Looser strings also seem to have more power because they tend to hit farther, probably due to their prolonging contact with the ball while the racquet moves upward with the stroke. String tension has a profound effect on the way a racquet performs and feels. I've seen lots of players hate a racquet strung at one tension, then love an identical frame strung differently. (This is a good point to keep in mind when trying racquets you're considering buying.) There's no single best tension, and the pros offer little guidance, with a huge range in their preferred tensions and no apparent correlation to style of play.

If you don't hit particularly hard or with much spin, and you want more power or your arm hurts, looser strings make sense. When looser strings compress more, the impact of the ball occurs over a longer period of time, thus making the shock less severe at any one moment. If you like to hit quite hard or with a lot of spin, tighter strings are probably your better choice. As noted, you'll have more control, and you'll get more spin because the ball will flatten out more on your strings, giving each string a better bite on the ball.

What's the best string?

There's generally a trade-off between resiliency and durability. The most durable strings, such as Kevlar, are extremely stiff. Highly resilient and/or thinner strings, which many players find offer a better feel, tend to break faster. Many strings have durability and resiliency (or playability) ratings on the package.

Durability is a must for me, and I like a moderately stiff string bed, so I use Kevlar main strings with synthetic gut cross strings. (Mains wear out much faster than crosses and are almost always the ones that break.) I string the crosses ten pounds tighter than the mains so that the stiff Kevlar in the mains won't prevent the more resilient crosses from providing some rebound effect on the ball. If the Kevlar were as tight as the synthetic gut, its stiffness would not let the ball ever "get to" the synthetic gut.

Finding strings you really like can require some experimentation. If you start by deciding how much durability you require, then you'll be able to stick with the results of your play-testing. There's no point falling in love with highly breakable strings if you're a big spin hitter who can't afford to chew through a pair every week. The performance of Kevlar strings seems fairly consistent across different brands, but other types of string are less predictable. Two brands with similar resiliency and durability ratings can feel quite different. If you bring comments such as "too springy," "too soft," or "too stiff" to the stringing technician at your pro shop, he or she should be able to point you toward strings that feel more like what you want.

Expert tennis tips

Tensioning For Conditions

Various playing conditions and circumstances can challenge the expertise of your stringer . Considering the following stringing variables can help fine tune a racquet and remember that 2-3 lbs of tension will be lost as soon as you start hitting a ball!

Court Surfaces

On hard surfaces (such as cement), the ball tends to move faster because less energy is absorbed from the ball by the court. To regain control of “fast” ball play, consider raising tension for most players. On soft surfaces (such as clay), the ball moves slower. Players have more control and more time to react. Drop tension (2-5 pounds) for clay court players to add power and depth to their shots.

Altitude & Temperature

At higher altitudes, balls move faster because there’s less friction in thinner air. (High altitude halls, slightly deader than normal, are often used for tournament play.) High temperatures cause balls to move faster as the heat-softened rubber ball becomes more pliable and easier to propel. Consider raising tension 2 to 4 pounds. The opposite is true in colder, damper weather.

Injury

Arm or wrist troubles may require a reduced tension to get depth and power without as hard a swing. Also suggest as large a grip as your customer can comfortably hold. Temporarily switching to a thinner and/or more elastic string will also help. If the player’s budget allows, recommend natural gut, which offers the most comfort and power.

Baseliner or Serve & Volleyer

Type of play can dictate tension preference as well. Many baseliners will want a lower tension to give them additional power to hit deeper shots. Serve and volley players may want higher tensions for control and accuracy in their net game.

Weather

Playing in rain makes the balls heavier. Hitting with a tightly strung racket forces water to spray from the ball but there is reduced energy on the ball. String with lower tensions – perhaps 5 lbs or more for greater power.

Tension Conversion

Kilogrammes (kgs) to Pounds (lbs)

(pounds are approximate to nearest 0.5 lb)
1 kg.= 2.2 lb  1 lb = 0.45 kg

String Gauge Conversion