In the past few weeks, more than a few very good players have asked me to add more lead to their racket hoops.
All wanted a little more stability, especially when dealing with heavy balls, or when returning hard first serves. Most of these folks already have their swingweights in the 320s to 340s region. So I thought it was decent enough. After reviewing some of their shots in question, it seemed to me that the problem was a little more string related than racket. Most were using stiff frames of RA68 and above. All were strung with full poly above 50 lbs. To me, that was the problem. Let me explain... Playing tennis is managing a series of collisions between stringbeds and a tennis ball. When both the racket and stringbed is very stiff, and the ball is new, hard and bouncy, where does the energy dissipate? Some of the impact energy would be absorbed by the racket, stringbed or tennis ball. But not all. So the racket, deflects backwards or twists and turns. And the ball compresses too. I have posted this slow motion video of Federer's racket wobbling on impact. Here it is again. Take a look at 1:16 in the video below. That's the racket flexing and absorbing the energy on impact.
Stiff frames with tight strings would always be less stable than softer frames, or when strung looser. To prove the point to an unbelieving player, we beefed up his stiff racket (with tight strings) to 365 swingweight, total weight about 360 grams and balance 32.5 cm. Then got him to try returning first serves from his coach. Same twisting. Same instability. Eventually, he moved a gauge up to a slightly thicker string to compensate for a slight drop in tension and obtained his desired stability. Some may claim the thicker string added weight as well. Yes it did. Merely 2 grams.
Some months back, a junior competitive player asked for advice on how to continue playing with an arm injury. Then, he was using a Babolat strung very tightly with full poly. Switching to a hybrid or even full multi did not help. I felt a more flexy racket was necessary. After testing different sticks, he made his choice and stuck with the new racket since. According to published specs, the RA was around the low-60s. During a recent restring, he started lamenting how the accuracy was still poor compared to his previous stiff Babolat. I was perplexed. He has been happily using the four new stick for about four months. Even managed to beat some team-mates he regularly lost to. Why the sudden nostalgia about his old Babolats? He rang up his coach, passed me the phone and we spoke. Top on my mind was whether he was "arming or swinging" (link) the new stick. This technique has huge implications on accuracy, especially when one is switching from a stiff flex to something softer. I also asked about his timing. All seemed well. To ascertain, I even dropped in on one of his training sessions to see for myself how he was hitting. And there he was, leaking some forehand shots just a tad right. First serve consistency was not as good as what I recalled. I borrowed and played a tie-break each with all four of his sticks. Then realised that the flex has changed! The rackets has all broken-in and the graphite has softened! The pieces started falling into place. Like when he mentioned that he felt he was not able to "load" the strings and "pocket" the ball as much as before. And the reduced spin. And the "not enough time" to shape the ball. It was finally confirmed after we put the rackets into a Babolat RDC machine. The RA stiffness for all four of them now measured 59, 60, 60 and 61 compared to 63, 64, 63, 65 when new. To address this, I proposed to: (1) add some lead tape to increase mass, which would "stiffen" the dynamic flex, &/or (2) lower the tension of his existing strings, &/or (3) change to a thinner gauge or softer string. As it was near an important competition, he selected option (2). It was a quick-fix that addressed most of his problems. His accuracy returned while the arm pain stayed away. Perfect!
