60 Minutes Interview

Excerpt from “Diego Schwartzman the Giant Slayer” on Paramount+

Recently the CBS 60 Minutes production team visited Dr. Brian Gordon in Miami to discuss the reasons height makes a difference in the performance capabilities of elite players. The interview was to acquire background for their profile of Diego Schwartzman who has defied common belief by reaching top 10 status despite his reported standing height of 5’ 7’’.

The interview was wide ranging, exploring the implications of height in tennis from a sport science perspective. The profile nature of the piece (understandably) caused most of the technical explanations to be edited out of the final production leaving behind only some of Dr. Gordon’s more general observations. “Diego Schwartzman the Giant Slayer” can be seen as a feature of 60 Minutes+ which streams on Paramount+.

A more detailed explanation of the importance of height is (possibly) interesting and explains a lot about why the top players in the world are just that. This article will discuss the technically rooted reasons that standing height is a benefit, or a detriment – reasons that hit the cutting room floor in the 60 Minutes piece.

There are many factors that determine a player’s ability to attain elite world-class status. In contrast to the past where certain limitations could be compensated for, today a player must rate high in all factors to make it to the very top. Currently the competition pool is too deep, and the athletes too strong and fast, for someone to overcome any inherent weakness in pursuit of the highest level of the sport.

We could broadly classify the factors as subsets of mental toughness, stroke mechanics, movement mechanics and tactical execution. Becoming an elite player requires working very hard to master all of these areas. The reality, however, is that many of the determinants of these subsets are genetically predestined. Though often hard to accept for players and coaches, ultimately elite genetics is the x-factor required to get to and stay at the top.

Elite Determinant Factors

• Mental Toughness
• Stroke Mechanics
• Movement Mechanics
• Tactical Execution

Among the most obvious genetic attributes of an athlete is height – how important is it really? Anecdotal evidence of trends on the pro tour could lead to the conclusion that height is an advantage in serving, particularly the first serve. On the other hand, it seems to be a disadvantage on return. One thing that stands out is that there exists an optimal height at which players can excel in both areas. These players are the most likely to reach true elite status in tennis.

There are several reasons a player’s height is important to their success on the court. The primary reasons include simple geometry, physiology and biomechanical considerations:

Geometry

Greater height implies a greater ability to reach vertically and horizontally. Vertical reach is most important on the serve (also overheads) and explains why taller players have an advantage in this area. Higher contact on the first serve allows faster shots to meet the demands of clearing the net and landing in the service box – simple geometry.

Horizontal reach is an advantage in contacting balls hit well away from a player. The extent of the advantage is amplified as the time to get to these balls is decreased. On a volley, for example, there is minimal reaction time so reaching ability is important. Horizontal reach is less important on ground strokes where increased reaction time favors movement speed over reaching ability.

Physiology

Greater height implies longer limbs which in turn implies longer muscles to move the limbs. A longer muscle is composed of more contractile units (sarcomeres) in series. Muscle physiologists indicate this is beneficial to speed of contraction but not to force production. Understanding of the physical demands of tennis suggests this would be a benefit to stroke production (upper body) but not so great for movement (lower body).

Stroke production requires the ability to move the segments and joints quickly against relatively small resistance. Longer muscles and faster contraction speeds should be an asset. Movement also requires rapid movement of the segments but against much greater loads (body mass) so logic dictates long muscles deficient in force production are likely a net detriment to movement.

Among the confounding variables in these observations is the fiber type distribution of the muscles. Physiologists have identified a few different types (genetically determined) that complicate the speed vs. force analysis. Some individuals have a higher concentration of fast twitch fibers (more force with faster fatigue) and some a higher concentration of slow twitch fibers (less force and less fatigable). More controllable variables such as training level are also a consideration.

Biomechanics

The longer segments (limbs) implied by greater height are beneficial to producing racquet head speed. The linear speed of the distal end-point of a segment is proportional to both the speed of rotation of the joint rotating the segment, and the length of the segment. For example, for a given rotational speed of the shoulder joint, the linear speed of the elbow will be greater for a longer upper arm than a shorter one. This effect is amplified across several linked segments interacting in a dynamic chain.

In the linked system used on tennis strokes it follows longer segments would allow faster racquet head movement all else equal. But the extent of the benefit is highly dependent on technique. On the serve the technique configuration of the segments is relatively similar among players in the upward swing (primary racquet acceleration phase) so taller players will realize an advantage. On ground strokes there is much more variability of segmental organization (i.e. bent elbow vs straight arm forehand) such that the inherent benefit of longer segments may be mitigated by choices in technique.

Greater height implies more body mass and a higher position of the center of mass of the body. Both of these factors make it more difficult to accelerate the body horizontally and this complicates speed acquisition and agility. The movement disadvantage of greater height makes it more difficult for taller players to get around the court and possibly explains the return of serve advantage apparent for shorter players. It is also possible that shorter players simply accept disadvantage in serving and dedicate more effort on return of serve to compensate.

There are advantages and disadvantages to height. Extremes on one end of the spectrum (short) or the other (tall) make it inherently more difficult to reach and stay at the highest level of the sport. It is pretty clear that for men the optimal height is in the 6’1‘’ – 6’4” range. Presumably this height averages out the benefits and detriments of the extremes. It also seems evident that this optimum is gradually increasing. So, what does that mean for outlier individuals to that range?

It by no means says that these individuals can’t be great players and enjoy tremendous success in tennis. And this was the point I made in the 60 Minutes piece (that hit the cutting room floor) – Mr. Schwartzman has had great success by excelling on return of serve and movement, developing adequate ground strokes and volleys, and mental and tactical toughness. It will be very difficult for him, however, to achieve the elite status of the perennial top 10 players like Federer, Nadal and Djokovic.