Robo-Mechanics: How the 40mm Ball Has Impacted the Game

It has now been several years since the change to the 40mm ball. Perhaps no rule change in our sport’s history has had such a major impact on the game. Coaches and athletes the World over have struggled to adjust the technical elements of play to take full advantage of the new ball’s playing characteristics. This has resulted in major changes in the way our sport is being played and taught.

Technical Changes Caused by the 40mm Ball

To best explain the 40mm ball’s impact on technique, let’s take a look at how the new ball size has affected the basic stroke elements. These elements consist of: how we contact the ball (amount of force or friction), when we contact the ball (timing), and were we contact the ball (point on the ball).

Increasing the size of the ball to 40mm has decreased both the overall spin and speed of the ball. However, the spin element has been much more affected with an overall loss of up to 18% of initial spin. In addition, the 40mm ball loses its spin and speed quicker while traveling through the air and also loses even more energy when it contacts the table than did the 38mm ball.

In simple terms, this means that heavy spin strokes are not as effective as they were with the 38mm ball and that the emphasis is now much more on force (forward) contact.

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