When purchasing or evaluating a new tennis racquet, one of the many specifications you’ll encounter is tennis racquet stiffness or frame stiffness. At first it may just appear to be another number in the list of specs provided by racquet retailers, however it’s worthwhile to consider racquet stiffness and to gain an understanding of how it impacts racquet performance.
Racquet Stiffness: Power & Control
One of the most common misconceptions with tennis racquet stiffness is that a more flexible racquet, that is one that bends or flexes under pressure, will produce more power than a stiff racquet that doesn’t bend as easily under pressure.
The assumption is that energy is returned to the ball when a tennis racquet flexes, as the frame rebounds during a swing. In theory this seems logical, however a tennis ball will only stay on the stringbed for a fraction of a second, which is less time than it takes for the racquet to recover.
As a result, the more flexible a frame, the more energy it absorbs, which results in a loss in power when hitting. Consequently, a stiff tennis racquet will flex significantly less during a swing and deflect more energy or power.
For this same reason control racquets, often referred to as players racquets, generally tend to have more flexible frames, resulting in less power potential for the racquet, but greater overall control.
As you can imagine, this statement is relative and highly dependent on a players overall skill level. That is, a beginner will not necessarily find an increase in control and accuracy simply by switching to a more flexible frame.
Rather a beginner might even find that they feel more control with a stiff tennis racquet that provides them with the ability to generate more power on their shots, which is frequently the case with power racquets, the type of racquet often recommended for beginners.
As an example, the Wilson Pro Staff 90 BLX used by Roger Federer has a stiffness index or rating of 65, compared to the Wilson K Factor KZero tennis racquet, which has a rating of 70 and is geared towards beginners.
Helpful tip! Want to learn how to select the ideal racquet stiffness? Click here to check out our 3 simple tips that will help you find the perfect tennis racquet for your game.
Racquet Stiffness and Comfort
Beyond power and control, racquet stiffness also has an impact on comfort. As a general rule of thumb, a stiffer tennis racquet will tend to pass more vibration and shock to the players hand and arm, which can result in discomfort with prolonged use.
More flexible racquets on the other hand will deflect more energy upon impact sending less vibration or shock to a player’s arm. However, it’s important to note that these are are both generalities.
In other words, a stiffer racquet doesn’t automatically mean it will be less comfortable than a more flexible frame.
Going back to the example above, the Wilson K Factor KZero is 3.5 ounces lighter than the Pro Staff 90 BLX. For most beginners or players that don’t have a tremendous amount of strength, this would be a significantly more comfortable racquet to play with, even though it’s has a stiffness rating that is 5 points higher.
This brings us to the most important note about tennis racquet stiffness and comfort.
At the end of the day racquet comfort is extremely subjective in that every player will find varying degrees of comfort with an identical racquet.
What’s more is that two racquets with near identical stiffness rating can both feel very different to the same player, so it’s important that you take the time to come to your own conclusions when evaluating a new racquet.
How Is Tennis Racquet Stiffness Measured?
As you can imagine racquet stiffness is not something that’s easy to measure without the right equipment. As a result, companies have developed specific machinery to help measure a variety of tennis racquet characteristics including racquet stiffness.
Perhaps the most common machine for measuring racquet stiffness is the Babolat RDC (racquet diagnostic center), which measures racquet stiffness, weight, swing weight, balance and string bed deflection or how much life is left in the strings of a tennis racquet that is strung.
Racquet stiffness is measured by by applying pressure to the tip of the racquet head, whish causes the frame to slightly flex. Through this process the Babolat RDC, and similar machines, are able to calculate the racquet stiffness index or rating for a given racquet.
The range or scale for stiffness for racquets will usually fall somewhere between 50 – 85, where the lower number indicates a more flexible racquet and the higher number a stiffer racquet.
The majority of modern racquets will usually fall on the scale somewhere between 60 – 75.
All these measurements can be taken for a given racquet within a few minutes and they are great for comparison purposes.
However, machines like the Babolat RDC are not easy to come by, so the easiest way to get a wide variety of the specifications for any given racquet is to check out your favorite online retailer as they typically provide this measurement for comparison purposes.
Tennis racquet stiffness is one of many criteria that can be used to help evaluate tennis racquets so that you can make an educated decision purchasing a racquet. However, nothing beats getting out there and testing a racquet for yourself. To help you find the perfect racquet be sure to check out our list of the 20+ best tennis racquets for 2018.
Once you find a racquet that you feel fits your needs take the time to demo the racquet. With each racquet you play with you’ll gain more perspective, which you can use as a point of reference for future comparison.
Still have questions? Feel free to post a comment below – we’d be happy to help!
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