In tennis, the strings are the part of a tennis racquet which make contact with the ball. The strings form a woven network inside the head (or "hoop") of the racquet.
The material used in tennis string can significantly change the performance of a racquet, especially for advanced players. Thus, several different compounds are used to make tennis strings, varying in terms of playability, durability, and "feel," among other considerations.
Natural gut is considered by many to be the best string in terms of overall playability, as it offers both power and control over the ball. However, natural gut breaks easily and is the most expensive kind of string; thus, it is usually used by professional tennis players. The first natural gut tennis string was manufactured in 1875 by Pierre Babolat
, who would launch the VS brand of gut fifty years later.
Natural gut is produced by drying fibers extracted from a part of the cow intestine called the serous membrane, or serosa, which contains collagen designed to withstand the stretching and contraction of the intestine. It is this elasticity that makes the fibers useful for tennis string. Although sheep intestines have also been used for racquet strings in the past, it is a myth that gut string was ever made from cats.
Synthetic gut is used by most tennis players. It can be made of any of a wide range of artificial materials (such as nylon
), making it cheaper, more durable, and easier to manufacture than natural gut. Synthetic strings are marketed as either "monofilament" or "multifilament;" monofilament strings are composed of a single, thick strand of material, and multifilament strings are composed of several (up to thousands) of smaller strands.
Nylon is generally considered the most popular tennis string. Wear-resistant coatings for nylon strings are common, especially with multifilament strings, because the outside filaments tend to break as the racquet is used.
strings are typically stiff, and were originally intended for use by frequent string breakers because of their high durability. However, due to their low power, players are able to put more spin and control on the ball with a full swing, making the string extremely popular on the pro tour.
is the stiffest, most durable synthetic string available, and is thus extremely hard to break. Kevlar is often strung with another string, such as nylon), in order to combine both strings' qualities, as Kevlar by itself feels too stiff for many tennis players.
The "gauge" number determines the thickness of the string. A string rated with a high gauge number is a thinner string; some gauge ratings also have a "Light" version, which is referred to by placing an "L" after the original rating's number (e.g., "15L"). Strings are usually rated at one of five common gauges; 15 (thickest), 15L, 16, 16L, and 17 (thinnest). String gauge is usually not of much concern to beginning tennis players, but can be very important to advanced and professional players.
Typically, a higher gauged string performs better. For example, the thinner 16-, 16L-, 17-, and 18 gauge strings are more lively and elastic than the thicker 15 or 15L. Thin strings are also known for better performance in creating spin and providing better feel. However, high-gauge strings also break faster, simply because there is less material to wear out.
Virtually all modern raquets are strung in a criss-cross horizontal-vertical pattern. Various other patterns have been used in history with varying success.
Double strung tennis racquets were introduced in 1977 but were later banned because they permitted excessive spin and were too successful. However, a modern version of the double strung racquet has been introduced that is legal to use.
Racquets are strung either with two separate strings (and thus four knots), or with a single string (resulting in only two knots). Sometimes, a hybrid of two different string types may be used in the same racquet. Traditionally, a double half hitch has been used to tie off tennis string, along with a starting knot.. Recently, a new kind of knot has been used called the "pro-knot," "Richard Parnell knot" or "half hitch knot with a tail. Along with the use of a starting clamp, this can make all the knots identical, and improve the aesthetics of a string job.
The process of installing strings in the racquet is called "stringing," and is done with a racquet string machine. These machines vary in complexity, accuracy and price. Stringing a racquet can take up to an hour for a novice, or around twenty minutes for a skilled stringer; during professional tournament a very skilled stringer may be asked to string a racquet while the player is on court. These stressful string jobs may not even take 10 minutes for a seasoned tournament stringer.
Drop Weight stringers
These inexpensive stringers use a weighted bar to achieve the desired string tension. They are the smallest of all stringing machines, making them the easiest to transport. This, plus their affordability, makes them popular among those beginning to learn racquet stringing. However, they take much longer than other stringers, and so are impractical for professionals. Despite this, they are considered by many to be among the most accurate of stringing machines.
Manual crank (lockout) stringers
These stringers use a crank to achieve the proper tension, at which point it locks into place. These stringers allow racquets to be strung quickly, but the string job will lose tension more quickly than racquets strung on drop weight or electronic stringers.
These stringers control the tension with a computer-directed electric motor, allowing for quick work and high performance. This is the most common kind of stringer found in stores and pro shops, but is also the most expensive. There are 2 types of electronic tension; Constant pull and lock out. Constant pull like the name purposes, pulls the string and continues pulling until the desired tension is reached making stringing more consistent and accurate as they compensate for the string stretching, the clamp loosing and slippage. Lock out electronics are similar if not the same as cranks, they will pull to your desired tension and will pull no more. Therefore lock outs are not as accurate as the constant pulls because they don't compensate for tension loss.
The "string tension"
of a racquet, usually expressed in pounds
, indicates the pressure under which the strings are secured to the frame. The string tension affects a racquet's playing characteristics, such as the "feel" of the ball, control over the ball, as well as maximizing power.
All racquets come with recommended string tensions, most of which lie between 50 to 70 pounds. Generally, players who prefer to feel the ball more, and assume better control over soft shots string their racquets tightly, with a high tension. Players who want to control the ball while maximizing their strength for hard shots will string at a lower tension.
A loosely strung racquet will usually have a larger sweet spot and will hit farther, but when swung hard enough, it will shoot balls unpredictably; a tighter string job will help make delicate shots with more finesse and control.
An extremely tightly strung racquet cuts down on a tennis player's feel on the ball, but can give the player excellent control if swung hard enough, with a smooth stroke. Such tension may make delicate shots more difficult, but makes play from the baseline more constant. However, if a player often hits powerful shots, a tightly strung racquet may quickly tire the arm, possibly resulting in tennis elbow.
It is advised by many professional stringers to string your racquet with the lowest tension possible while still being able to maintain control of the ball. Beginning players trying to find their tension should start in the middle of the recommended tension range and adjust the tension from there to meet their needs. The recommended tension is usually printed on the racquet. Remember, with a lower tension the racquet will have more power and less control, with a higher tension it will have less power and more control.
Due to the tension present on the strings, elasticity and tension begins to decrease the moment they are installed in a racquet. "Dead strings", or strings which have lost their tension, cut down on the performance of a racquet. Dead strings may also hamper a tennis player's ability to generate power and pace, and may even make his arm sore.
The frequency of restringing depends on the player and the racquet, but there are a few recommended intervals. One is to restring the racquet as many times in a year as the player uses it in a week; e.g., if the racquet is used three times per week, it should be restrung three times per year. Another guideline is to restring after every 40 hours of play; if the racquet is used three times per week and three hours per session, it should be restrung approximately every five weeks. If the player has access to a tennis string tension meter (or access to a pro shop equipped with one), he may restring his racquet after he measures a loss of 25% or more of stringbed stiffness. However, many players who hit the ball well enough to break the strings simply restring rackets whenever the strings break.
A "ping" should always be heard when the racquet face is struck against the palm of the hand. If not, or if there is a "thud" sound instead, the racquet needs to be restrung.
United States Racquet Stringers Association
The United States Racquet Stringers Association (USRSA) offers two levels of certification for stringers: the Certified Stringer and the Master Racquet Technician, of which around 350 exist worldwide. The Master Racquet Technician certification process includes testing of the stringer's ability to string a racquet, perform grip work, identify mistakes in an improperly strung racquet, and pass a written test that covers not only strings, but racquet technology as well.
Since 2004, RSi, the USRSA's monthly magazine, has named a Stringer of the Year. Past winners were:
- Randy Stephenson, Texas (2004)
- Bob Patterson, Alabama (2005)
- Grant Morgan, Tennessee (2006)
- Tim Strawn, Virginia (2007)