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Here is a story about Nadal's racquet weight…What does it mean? Does it make sense? "Babolat…told us that rather than focusing on the overall weight of the racquet, they have fine-tuned Nadal's racquet swingweight by seven points to make it more headheavy and provide extra punch through the air.—Howard Beale
Nadal and company indeed chose to make only minuscule changes to the racquet's "overall weight," focusing instead on slightly altering its balance and swingweight. So where does Nadal's Babolat AeroPro GT currently stand? According to Jean-Christophe Verborg, International Sports Marketing Director at Babolat, the frame's new specifications (unstrung and without overgrip) are as follows:
WEIGHT: 314 grams / 11.08 ounces—versus 311 grams / 10.97 ounces, in 2011
BALANCE: 32.63 centimeters / 5.2 points headlight—versus 32.50 centimeters / 5.6 points headlight in 2011
SWINGWEIGHT: 316—versus 308-310, in 2011
The racquet's total mass, as you can see, has increased by three grams, a measly sum. In itself, this is not a very significant change. But when we consider where the weight was placed—read: toward the tip of the racquet—we start to see a difference, specifically a more headheavy balance and an increase in swingweight. These tweaks, in Verborg's words, should effectively give Nadal "a little bit more power" off the serve and the ground "without changing the global specifications of his racquet too much." How much more power, however, is yet to be seen.
What exactly is "swingweight"? I hear this term thrown around all the time by racquet gurus at my club, and am puzzled about what it means.—Joan
That's a good question, Joan. Swingweight—usually determined with a fancy piece of equipment called a Babolat Racquet Diagnostic Center—tells us how heavy a racquet feels to swing. In short, swingweight is calculated by cobbling together two variables: (1) mass (or how much the racquet weighs) and (2) balance (or how that mass is distributed along the length of the racquet).
"Consider a rod," as Cross and Lindsey do, in Technical Tennis, "that is the same length as a racquet (say 700 mm) and that weighs 280 grams. The balance point will be in the middle of the rod, 350 mm from each end, if the rod has its weight uniformly distributed along its length. It will feel the same to swing regardless of which end you hold. Now suppose we add 20 grams so that rod weighs 300 grams. Being heavier, the rod will feel heavier to hold. We can add the extra 20 grams anywhere we like and it will still weigh 300 grams. However, the balance point and swingweight each depends in different ways on where we put the extra 20 grams, and this will affect the way it feels to swing the rod."
If, for example, we place that 20 grams at the midpoint, the rod will remain evenly balanced, and the swingweight will increase only slightly—simply because of the 20 grams of added weight. But on the other hand, if we place that 20 grams opposite the end of the handle, the rod's balance will shift toward the tip—the rod effectively becomes "headheavy"—and the swingweight will increase significantly. Though both rods weigh the same, their balances are different; the second feels heavier to swing and thus has a higher swingweight.
An increase in swingweight of 6-8 points translates to a ~3 gram increase at the tip of the racquet. Since that could be less than the difference between one set of strings and another, and it is literally less than the weight of most string dampeners, this is truly a tempest in a teapot. Why is Rafa making such a fuss about this? And talking about how hasn't gotten to practice enough with it? And how it'll get worse before it gets better but it'll be worth it?—d
It's true, d, that a three gram difference, at least in a laboratory setting, has an extremely small effect on a racquet's performance. But even though three grams, for all practical purposes, does not change much in the way of racquet to ball contact, that added weight does alter how the racquet feels in hands of an experienced player. Back at last year's U.S. Open, Tom Perrotta wrote a very interesting piece for the Wall Street Journal, in which he tried to determine how attuned long-time pro Michael Russell was to small changes in his equipment. What he found was surprisingly impressive: Russell, Perrotta wrote, "is so familiar with his racquets he's able to register a weight difference as small as one gram, or about four-hundredths of an ounce." Four-hundredths of an ounce! This is truly negligible. But Russell can feel it, and it has to feel right; if it doesn't, his play suffers. "Racquet performance," as Cross and Lindsey perceptively note, "is as much psychology as reality."