The Importance of Elongation PercentageMatt Steverson
While I was working on this post, it amazed me to see Tim resurrect his earlier writings on the causes of tennis elbow and, right there, one of the major problems surfaced: avoiding strings with too little elongation.
Unfortunately, string companies don’t publish information like this on their products and, with the popularity of polyester strings (of which very few have much elongation at all), the emphasis has turned to stiffness, not elongation. Stiffness is, I think, not the best indicator of string comfort; elongation percentage is a much better source of information.
What is Elongation Percentage?
Simply put, elongation percentage is how much an item stretches under tension, measuring how “ductile” (able to remain pliable) it is. A higher-elongation string can dissipate energy (stress) better than one that stretches less, which should make it more comfortable during play, while also putting that energy back into the ball for increased power potential.
How do You Test for Elongation Percentage?
While we don’t have reliable sources for the elongation percentages of most strings, it’s quite easy to do a rudimentary test in the field. Historically, we have tested elongation percentage at 60# tension, and that is the tension that I have tested at over the years.
My procedure is, while not necessarily what manufacturers do, quite simple: I clamp a length of string in the machine, measure it (in millimeters), apply 60# tension, measure it again, and take the percentage increase in length as the elongation percentage of that particular string.
I’ve included elongation percentage measurements for several strings below, and will update them as often as I can. If you have a string you are curious about, let me know and I will get to them when I can.
How Does Elongation Percentage Help Us as Tennis Players?
For most tennis players, the comfort and power levels of a string are much more important than spin potential (since most players don’t hit a lot of spin) or durability (since a lot of them don’t break strings before their useful life is over). It is incumbent upon us, their racquet technicians, to know which attributes are most helpful to them and educate them about it. Elongation percentage is, in my opinion, at the top of the list.
|Brand||Model||Gauge||Color||Type||Elongation % @ 60#|
|Alpha||Gut 2000||17||Natural||Multi Nylon||21.1|
|Viper MXT||17||Gold||Solid Core SG||5.36|
|Pro Hurricane Tour||16||Yellow||Mono Polyester||5.03|
|Bow Brand||Championship||16||Natural||Natural Gut||9.85|
|Clarke||Nylon||15L||Natural||Solid Core SG||12.5|
|Dunlop||Explosive Red||16||Red||Mono Polyester||9.7|
|Synthetic Gut||16||Natural||Solid Core SG||12.9|
|Forten||Sweet 16||16||Natural||Solid Core SG||9.6|
|Gamma||Live Wire XP||17||Natural||Multi Nylon w/ZYEX||8.97|
|TNT2||16||Natural||Solid Core SG||13.59|
|Gosen||OG-Sheep Micro||16||White||Solid Core SG||10|
|Polylon Comfort||17||White||Mono Polyester||5.4|
|Kirschbaum||Super Smash Spiky||16L||Gold||Mono Polyester||6|
|Touch Multifiber||16L||Gold||Multi Nylon||13|
|Luxilon||ALU Power||16L||Silver||Mono Polyester||6.67|
|Big Banger Original||16||Beige||Mono Polyester||4|
|Prince||Lightning XX||16||Clear/Silver||Solid Core SG w/foils||15.04|
|Synthetic Gut Original||16||Gold||Solid Core SG||8.96|
|Pro Supex||Premier Ace||16L||Orange||Mono Polyester||3.7|
|Signum Pro||Poly Plasma||18||Orange||Mono Polyester||4.04|
|Tecnifbre||NRG2||16||Natural||Multi Nylon w/PU||8.3|
|X-One Biphase||16||Natural||Multi Nylon w/PU||8.72|
|Topspin||Cyber Flash||16||Silver||Mono Polyester||3.47|
|Poly Power Soft||16||White||Mono Polyester||3.68|
|Wilson||Natural Gut||16||Natural||Natural Gut||8.97|
|Yonex||Tour Super 850||16||White||Multi Nylon||12.4|