In the more than 30 years since the introduction of super-lightweight, super-powerful, hollow-tube carbon fiber composite racquets, countless attempts have been made to make them comfortable to use. While carbon fiber racquets have become the industry standard today, and most iterations are more comfortable than their predecessors, they still remain generally stiff, which keeps them uncomfortable to play with and hard on players' bodies over time, especially when combined with super-stiff polyester strings. What was gained in power via composite carbon-fiber was sacrificed in comfort and control. This dichotomy of power versus comfort-control has accelerated since hollow-tube carbon fiber racquets were first introduced: carbon composites do not absorb vibration and impact-shock energy effectively. Players, coaches, racquet designers, and distributors are aware the problem of comfort, without sacrificing power, must be addressed with a serious viable solution.
Just prior to the debut of hollow-tube composite racquets, carbon composites primarily were used to reinforce wood racquets. By laminating thin sheets of the super-strong carbon material to a wood frame, the frame was made stiffer, therefore more powerful, as the wood maintained comfort by absorbing vibration and impact shock. Without wood at the core of a carbon-composite racquet, the composite material is left to absorb impact shock and vibration on its own, which, given physics and the nature of the material, it cannot do. Carbon composites, otherwise known as reinforced plastic, tend to be brittle and inflexible, and inherently unable to absorb energy. All factors that categorize carbon composites as among the worst materials to use in a tennis racquet with an expectation of absorbing vibration and the effects of impact shock. Wood, on the other hand, is one of the best shock-absorbing materials in tennis racquets. But wood is also the heaviest material. Hence the modern racquet design dilemma: How to make hollow-tube carbon-composite racquets as comfortable as wood racquets, yet maintain the best properties of carbon-composite racquets, particularly their great strength-to-weight ratio, along with their amazing strength and stiffness?
A number of different design approaches have been developed over the course of 30 years to alleviate the discomfort and harshness of the modern hollow-tube composite racquet frame. Consider an early attempt: handle-dampener designs. As the name implies, the design involves placement of an energy-absorbing mechanism or material in the handle. Extra weight easily can be accommodated in the handle of a hollow frame, without destroying the overall weight and balance of the racquet, making the handle-dampener approach relatively easy to execute. Most modern high-performance racquets incorporate some version of handle-dampening design.
A second method toward reducing discomfort and vibration in the design of a modern composite racquet is the use of frame gaskets. The Wilson Triad racquet is one good example. The Triad design breaks the racquet frame into separate parts. The handle and throat are fabricated as one part, and the head frame as a second part. The two parts are then connected to form an entire racquet frame. Rubber gaskets are then located at the connecting junctions of the two parts. The idea is that by separating the head-frame part from the handle-part with rubber gaskets, vibration and shock waves traveling from ball impact to the handle will be disrupted at the junction of the two parts and dampened by the gaskets.
A third attempt to improve the comfort level of a modern racquet is by use of an internal dampening mass. One popular line of racquets using this approach is the Kinetic from Pro Kennex. Secured within the head frame of a Kinetic racquet are a multitude of pea-sized capsules filled with tiny micro-beads. This moveable mass absorbs vibration and impact energy. A simpler technique, with a similar objective, is to fill the hollow frame with a lightweight, energy-absorbing foam.
The latest route to achieve a comfortable racquet is the result of advances in technology. The evolution of carbon composite material itself over the years allows for elevating the comfort level of hollow-tube composite racquets. Specifically, the use of chemical additives softens the plastic resin that cures and hardens carbon fibers into shape. Unlike previous iterations of carbon composites, newer compositions contain softening additives so the fibers are no longer brittle, allowing improved vibration-dampening properties. The advantage is the high strength-to-weight ratio and inherent stiffness of the composite material can be maintained, while vibration dampening improves.
An extreme version of carbon composite softening has made its way into super-flex racquets popular in the market today. Super-flex racquets are so flexible they mimic the performance of wooden racquets by bending (and twisting) at ball impact. Because super-flex frame models absorb a great amount of energy, they are extremely comfortable. Unfortunately, many of the best qualities of composite material have been sacrificed in the process. Strength, accuracy and stability, and the inherent stiffness responsible for power in a racquet, have all been decimated in the pursuit of comfort. Forsaking power, stability, and accuracy, as many of the biggest brands in the industry have done to achieve comfort, is indicative of a fundamental issue which plagues modern racquet performance.
Obviously, there have been many effective solutions toward increasing comfort and improving the feel of modern racquets since the debut of the hollow-tube composite frame. All provide varying degrees of relief from vibration and impact-shock energy. All are represented in the market with well tested and commercially successful versions. While a broad range of solutions, from handle-dampeners to kinetic micro-beads, may seem different from one another, all approach a solution in the same way: post-impact designs.
The initial premise of post-impact design accepts that vibration and impact shock will be transferred directly into the racquet frame and eventually into its handle. Dampening works after impact, after vibration and shock energy have entered the frame, to reduce that unwanted energy as much as possible. Post-impact solutions are directed toward the residual effects of ball impact, not the ball impact itself, a critical distinction from a pre-impact solution—an innovative solution only one racquet company has fully developed.
Is there a solution that maintains comfort, doesn't diminish power as a result, and doesn't accept a direct transference of vibration and impact-shock energy from ball impact? Is there a design that addresses ball impact itself at the point of impact? A design that actually reduces the initial ball-impact energy and vibration before it transfers to the frame? A pre-impact design solution? A racquet that addresses pre-impact shock doesn't need to be filled with foam, or a moveable mass, or fitted with a handle-dampener. A pre-impact racquet design doesn't need to be made hyper-flexible either, to be as comfortable as wood.
The logical and natural pre-impact solution in tennis racquet design is string-bed suspension, where the strings are held in tension on a suspended structure apart from the frame. It's akin to an automobile suspension, where the wheels are held in place by a suspended structure apart from the chassis. Automobile suspension is a pre-impact design solution.
Scientifically, there isn't much of a difference between the various types of post-impact approaches to reduce vibration and the residual effects of impact shock in a modern hollow-tube composite racquet. Post-impact designs address unwanted energy after it enters the frame. Pre-impact design addresses vibration and ball impact as it occurs, before transference to the frame, eliminating most of the adverse effects of ball impact energy.
The most critical benefit of pre-impact string-bed suspension design is that it achieves its objectives without compromising the best properties of the space-age composite material used to fabricate a racquet. String-bed suspension optimizes the inherent strength and stiffness of carbon composites by tackling comfort and ball rebound speed, so the frame still can be stiff, i.e., powerful, stable, accurate, and precise. Pre-impact suspension design enables a new engineering paradigm for racquets in which power, control, and comfort can be optimized as one force.
Is there a most comfortable racquet ever? The science says there is. The science says that a pre-impact suspension design is the path toward the most comfortable racquet possible. That most comfortable racquet is available now. It's called a BOLT, and it's equipped with a patented pre-impact spring suspension design called a Zipstrip.
Comfort of both strings and racquets is a huge issue in tennis and, when not addressed, can be harmful to players and to the long-term health of the sport. Stiff racquets and stiff strings can cause debilitating and career-ending injuries. They can cause pain and discomfort that keep new players from joining in and limit how often frequent-players can play. But a too-flexible racquet, while it doesn't hurt as much, doesn't hit as well, either. While we must address the impact shock and comfort issue, there is no need to sacrifice carbon composites. That's where the Zipstrip comes in: It absorbs ball impact energy right at the string bed, before it gets to the racquet and travels up to the arm. The Zipstrip provides comfort and ball rebound speed control, while the frame can remain stiff and powerful, stable, accurate, and precise. And it's not just the comfort that's improved. The Zipstrip, together with a strong, powerful frame, enables comprehensive elevation of racquet performance: longer dwell time, greatly improved spin potential, consistent ball release, improved accuracy and ball-flight control, and a far larger sweet spot than conventional racquets. Is BOLT the most comfortable racquet ever? Try it and see for yourself. If comfort is an issue, as it is for most players beginners to pros, then playtest a BOLT. Demo BOLT BOLT Racquet Lab