Racquet Choice and Effects on Tennis Elbow
Simple fact, no one enjoys the experience of pain associated with tennis elbow. An unfortunate statistic is that close to 50 percent of tennis players will, at some point, suffer from tennis elbow. When trying to pick out a new racquet, we would prefer that tennis elbow not be a consideration, but for some it is. Whether that means that they are trying to prevent it, or heal it, it is a concern. So first let us understand a little more about this painful experience.
Tennis Elbow is caused by injury to the muscles and tendon areas around the outside of the elbow. Most often, the pain is centralized around the area where the tendons attach to the bony outside part of the elbow, known as the lateral epicondyle. There is also an injury known as golfer’s elbow, which is nearly the same but affects the inside of the elbow instead. Typically, the pain of tennis elbow is present in the dominant arm, largely because it is essentially an overuse injury. This means that repeated stresses on those muscles and tendons, such as hitting a large number of groundstrokes, can certainly contribute to injury.
The toughest part of dealing with tennis elbow is that it affects your everyday life in so many ways. The pain can quickly flare up while performing typical daily activities such as turning a doorknob or opening a jar. It can also be aggravated by squeezing or lifting even light objects. This is why many cases of tennis elbow take so long to heal, if they ever fully heal at all. The reason that it is so difficult to heal relates to the combination of inflammation and constant agitation. While it may only be small motions like using a screwdriver or kitchen utensils, their use applies small amounts of strain to the already injured muscles and tendons. With any sort of inflammation-related pain, healing requires rest that is difficult with an injury that affects a commonly used muscle.
On top of this difficult situation, tennis players never want to give up playing in order to let the injury heal as they should, continuing to place high amounts of stress on the elbow. In this article, we are going to focus on the racquet and what kind of frame to look at to lessen the impact for those players who choose not to heed medical advice and rest. These rules would also apply to players returning from an extended break due to tennis elbow and want to limit their risk in the future.
Unknown by many, and the primary cause of most tennis elbow cases, is quite simply improper technique. A harsh racquet or stiff strings will not help the cause, but things such as technique, timing, and stretching play a much more important role. Let us assume that a player over rotates their forearm on their one-handed backhand trying to achieve more topspin. This creates high amounts of risk due to a number of factors. For one, the repetitive rotation of the forearm, coupled with a higher chance of mishits poses a threat. Now let’s assume that the player has sound technique, only mishits occasionally, but still winds up with tennis elbow. How do we react to this?
The first step is to make gradual changes to the equipment that the player is using, trying to find a combination that they are happy and pain-free with. So what factors of a tennis racquet affect tennis elbow? First off, we are going to entirely ignore technologies as if they do not exist and focus onto on the controllable specifications of a racquet without any proprietary technology applications. So, a racquet is typically defined by the parameters of: weight, balance, swing weight, head size, length, flex, and string pattern. Of these seven properties, how many apply to comfort and tennis elbow safety? Unfortunately, the answer is all of them, to differing degrees. So let’s move down the list one at a time.
Weight: There are two ways to look at this parameter. The first is that if a racquet is too heavy, the player is likely to compensate with poor technique and late contact. A frame that is too light will lead to mishits along with a lack of stability and vibration absorption. Further confusing things is that some coaches will tell their students to find the lightest racquet that they can control, while others will stress to find the heaviest racquet that they can comfortably swing. This is based on personal opinion and style, but with regards to tennis elbow, it’s simple physics that says a heavier racquet purely has a greater mass to absorb shock and vibration. This is why we propose to find the heaviest frame that you can comfortably play from an arm comfort viewpoint. Please also keep in mind that static weight is only a part of a much more important piece that we will cover later on.
Balance: This one shares a paradox similar to static weight, but is typically linked to the static weight of a frame assuming that one does not wish to mess with lead tape. Once again, the important aspect with balance is to treat it like the Goldilocks paradigm. As the weight bias of the frame moves towards the handle, the racquet becomes easier to maneuver, lowering the risk of making contact late. In exchange for the faster movement, the head becomes lighter, lowering its own resistance to deflection and increasing its susceptibility to vibration and shock. Conversely, as weight is shifted towards the head, stability and dampening are increased at the cost of maneuverability. While the shock and vibration are decreased, the amount of torque that is placed on the arm at contact increases, presenting another serious problem. The ideal balance is the one in which you are able to experience the stability of the weight in the head, while still remaining mobile and comfortable. This is an example of where a polarized racquet weight distribution is considered superior to a non-polarized set up, but that is a topic for another entry.
Swing Weight: Remember how I told you that static weight and balance were linked, where here is the even more important and much less understood connection! While static weight is a measurement of the mass of the racquet at rest, swing weight can be considered a measurement of the mass of the frame as it moves through the air. The closest similar comparison in Physics is Moment of Inertia, which simplifies potentially difficult problems by determining the torque on an object based on the weight and the relative centralized location of that weight. In general, for a given static weight, the more the balance shifts towards the head, increasing the swing weight and bring its benefits as well as drawbacks. In a way, swing weight is a shorthand method of determining the amount of weight in the head that will be acting on an impact, so a higher value means greater stability and shock absorption, but also a greater amount of strain on the arm, especially noticeable on off-center hits. Once again, it is important to have enough swing weight to protect the arm, without having so much that it negatively impacts results and proper strokes.
Head Size: This is a fairly basic relationship that is much easier to understand using the assumption that all other aspects are equal. While this is typically not the case, for this example, we will assume it to be true. When it comes to comfort and arm safety, the larger the head size is, the better it is for the arm. The reason for this centers on the fact that a larger head size allows for a greater amount of deflection, resulting in a softer feel at contact. As the string is allowed to stretch and flex more, it is capable of absorbing a greater amount of the overall energy of impact, which it returns a high percentage of that energy back, propelling the ball in the opposite direction. By using a larger head size, you effectively decrease the stiffness of the string bed and give yourself a larger sweet spot, both properties that are conducive to arm safety by minimizing shock.
Length: While at first it does not seem that length would have a drastic impact on tennis elbow sufferers, it does work in a similar way to other variables we have talked about. Assuming that we can keep every other variable the same, only altering the length of a frame, a longer racquet will feel harsher on the arm. A typical fact is that a longer racquet will have a higher swing weight than a racquet of similar weight but shorter length. Even if we assume that the two frames have the same swing weight, the longer racquet will do more damage to the arm because the contact point is farther away from the arm. Based on our calculation of torque from before, by moving the contact point further away, the amount of torque and stress created on the arm increases, with this becoming even greater on off-center shots, a common occurrence as the ideal contact moves further and further from the body.
Flex: While flex sounds like it should be an easy to understand, it is slightly more complicated than the simple number that we or anyone else lists for flex. The unfortunate truth is that given current testing equipment designed for use on racquets, the flex is only measured at one point along the length of the racquet, that being the throat. While this can give a rough estimate for some frames, it does a disservice because many of the material compositions of frames today alter the stiffness based on the location along the racquet to serve specific purposes. A famous example of this would be tapered beam sections of the Wilson Hammer line of racquets. By making the beam width thinner in the throat area, it offered a softer flex when measured, but the much thicker hoop area of the frame was also significantly stiffer, which could not be easily measured. As expected, the stiffer a frame is, the harsher it is on the arm.
This is for two reasons: shock and vibration. It is important to realize that these are different aspects and they affect the body in slightly different ways. Shock is most often associated with hitting off center, as an extremely harsh torque felt especially in the hand, wrist, and elbow. This also occurs on shots hit in the sweet spot, but the energy absorption and repulsion of the strings do mitigate some of the impact forces, so the feeling is not as severe. Vibration on the other hand, is the residual waves of frequency that radiate down the frame and into the arm. This is typically not felt by the player on the court, and will usually only result in soreness after the fact, but can be enough to also cause problems. Most often this vibration is the result of a frame being too light that it is not able to dampen the incoming frequency of waves, but can occurs in heavier frames as well. Interestingly, shock is typically associated with stiffer frames, while vibrational damage is more likely in more flexible frames. While the more flexible frame will typically dampen the amplitude, or strength of the wave, depending on the frequency, it can still cause major problems to a players arm.
For this reason, when it comes to flex, the idea is to look for something that is relatively low in flex, but as frames become more flexible they tend to lose some of their stability. This, in addition to various technologies designed to alleviate tennis elbow, makes it difficult to judge a frame based on only one isolated flex measurement. For this reason, we suggest that you do not take the flex rating as an “end all” searching solution, but instead focus on it as a piece to a much more complicated puzzle. We will suggest to try to stay below a flex of about 65, but this will be somewhat dependent on the other pieces you feel most comfortable with.
String Pattern: This is another fairly basic relationship to understand. Assuming similar frames that are only different with regards to the string pattern, the more open pattern will provide a softer feel and less shock than a frame with a denser string pattern, assuming the same tension. This is because the greater number of string intersections will limit the amount of string bed deflection, in a way similar to a smaller head size will. The greater string bed deflection allows the unit to act as a softer entity in the energy transfer that happens at contact. This is beneficial because such a large percentage of the energy stored in the strings is returned to the ball, leaving a smaller amount of energy for the racquet and arm to absorb.
So after all of this, perhaps we should condense it down to Cliff's Notes version?
Static Weight: Heavier racquet absorbs a larger amount of shock, but can tire the arm and lead to poor contact.
Balance: More Head Heavy provides greater “effective weight” at contact, but creates more torque on the arm, especially on off-center shots.
Swing Weight: Higher swing weight provides greater “hitting weight” but can slow the swing and lead to poor/late contact
Head Size: Larger Head Size provides more forgiveness and softer feel, but can lead to loss of directional control.
Length: Longer racquet leads to contact further from the body and greater torque on the arm, especially on off-center contact.
Flex: Higher stiffness transmits shock with less dampening, placing acute forces on the elbow, lower stiffness absorbs more shock, but can transmit more vibration. Difficult to judge based on current measuring methods.
The String Pattern: More open pattern allows greater string bed deflection and more comfort but limits directional control.
So if you should be unlucky enough to get this problematic injury, please do not force yourself to continue playing. It is an overuse and inflammation injury and needs rest more than anything in order to fully heal. Once the pain is gone, be sure to work back into playing slowly with a focus on stretching before and after. In addition to these precautions, taking a look at your equipment is not a bad idea.