String Tension
Also known as: stringing tension, tension, pounds tension, kg tension
String tension is the tightness at which strings are pulled through the racquet frame, measured in pounds or kilograms, influencing the trampoline effect, control, and power of the string bed.
String tension is one of the most impactful and most misunderstood racquet customization variables. Lower tension (below 50 lbs / 22 kg) produces a more elastic string bed — the ball dwells longer on the strings, the strings absorb and return energy more efficiently (trampoline effect), and the result is more power with less swing effort. Higher tension (above 55 lbs / 25 kg) reduces the trampoline effect and gives the player more direct control over placement but requires more swing speed to generate the same pace. Most recreational players are strung too high; modern research suggests playing near the bottom of the recommended range or slightly below maximizes both power and topspin. Professional players use a wide range: Serena Williams used approximately 60 lbs while Dustin Brown has used as low as 40 lbs.
Example
A recreational player restrings at 48 lbs instead of their usual 58 and immediately finds more power without trying harder — the trampoline effect does the work the extra swing speed used to do.
Why it matters
String tension is adjustable and can meaningfully alter performance. SwingVantage recommends reviewing your string tension if your groundstrokes feel tight or if you notice an unusual number of frame errors at standard swing speed.
Frequently asked questions
Should I string tighter for more control?
Higher tension does give a denser feel, but it does not necessarily increase accuracy — it reduces power and can increase arm stress. Most players improve control through better technique rather than higher tension.
Related terms
- String GaugeString gauge is the thickness of a tennis string measured in millimetres or gauge numbers, with thinner strings providing more spin and feel and thicker strings offering greater durability.
- Polyester StringPolyester string is a stiff, low-elasticity monofilament string that provides superior spin potential and durability but transmits more shock to the arm compared to natural gut or multifilament strings.
- Natural Gut StringNatural gut string is made from cow intestine and offers the highest elasticity, best tension retention, and greatest comfort of any string material, at a significant cost and durability trade-off.
- SwingweightSwingweight measures how heavy a racquet feels when swung, accounting for where its mass is distributed. Higher swingweight gives more plow-through and power but is harder to maneuver.
- RA / StiffnessRA is a racquet’s stiffness measured by how much the frame deflects under load. Higher RA (66+) means a stiffer, more powerful but harsher frame; lower RA (under 58) flexes more for feel and arm comfort.
Related guides & benchmarks
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