Vibration Dampeners – Do They Have The Right Vibe?
What benefits do vibration dampeners have for tennis players?
Near any tennis court, you can hear the signature thwack of the ball hitting the racquet. However, it’s not just noise produced by a tennis ball hitting a racquet, it’s vibrations from the strings. These vibrations are more than just a sound effect – they can cause tangible damage to players’ arms.
When a string vibrates, it has one main force causing it to do so – the restoring force. In simple terms, the restoring force pulls a tensed string back to its normal equilibrium position. For a tennis racquet, the strings are stretched by the impact of the ball, which then sets into motion the restoring force. This can be roughly modeled by the equation F = -kx, where F is the restoring force, k is the spring constant (the strength of the string), and x is the distance from the equilibrium position. The negative sign indicates that the force is always in the opposite direction of the displacement; that is, the force is pulling the string back toward its equilibrium.
For a tennis racquet then, the ball’s impact causes the strings to be displaced, which in turn causes the restoring force to pull the strings back to equilibrium. The resulting vibration transfers from the strings, through the handle of the racquet, and to a player’s arm.
A common solution to this is to use a spring dampener, which is a small rubber piece placed near the bottom of the strings of the racquet. These are usually simply a single circular piece, but some can be a line of rubber as well. However, the evidence regarding their effectiveness is inconclusive at best, with these spring dampeners mostly quieting the high-frequency noise of the impact but not the low-frequency vibrational force itself.
Spring dampeners are obviously a “low-tech” device, raising the question that there must be more sophisticated solutions for vibration damping.
This is what a 2019 study published in Sports Medicine and Health Science examined. This study tested a new vibration damping technology (VDT) for tennis racquets. The researchers recruited 19 Division I college tennis players (10 men and 9 women). Two rackets were tested: a VDT and non-VDT racquet. The rackets were identical across all characteristics (e.g., mass, size, shape, etc.) except that the VDT racquet included a layer of composite material – called Countervail ® – in the frame to maximize the dissipation of mechanical energy. Accelerometers were attached to the racquet, hand, and forearm of each participant to measure vibration. Then, each player performed repeated serves until they reached near exhaustion.
From this, the researchers found that in lab tests, the VDT racquet showed 74% less vibration force than the non-VDT racquet did. During real play, vibration force at the racquet was 40% lower while participants were “fresh” and 34% lower near exhaustion with the VDT racquet. Additionally, electromyography tests showed that there was reduced fatigue in the biceps and wrists when players used the VDT racquet, potentially leading to less arm injuries and strain. Finally, players became less exhausted in the same amount of time when using VDT racquet, compared to a standard racquet.
Overall, these findings point toward a positive future for more sophisticated vibration dampeners. The researchers were still cautious, noting the study’s small sample size and the fact it did not control for potentially influential variables such as grip force that can affect how strongly the racquet’s vibrations are transferred to the arm.
Nonetheless, the physiological evidence is hard to ignore. By absorbing shock at its source, the VDT racquet appeared to protect the forearm’s stabilizing muscles from overwork—at least during a 30-minute, high-intensity session. For athletes playing hours-long matches, this reduction could translate into meaningful improvements in comfort, consistency, and potentially even injury prevention.
So, the next time a tennis player delivers a blistering forehand and feels less sting in the arm, it might not just be their technique. It could be the quiet power of vibration dampening technology.
