Height affects performance in most sports. This is particularly true for competitive cycling.
During cycling, the contraction of muscles supplies the propulsion while wind resistance (drag) heads progress. The former is related to cross sectional area while the latter, surface area. Given both are related to a form of area, they would at first appear to offset one another as the body scales. However, drag scales to a lesser extent due to streamlining, thereby giving the taller cyclist an advantage on flat courses1. Hence, time trialists in the Tour de France tend to be among the tallest within the sport.
The work done by gravity is more varied as it resists and assists progress on ascending and descending, respectively, while it is minimal on the flats. And given the force of gravity scales more quickly with body height than do muscular force and drag (square-cube law), the taller person will be at a disadvantage when ascending and advantage when descending. Of the two, the disadvantage during climbing tends to have the greater impact on race outcomes, perhaps because the equalizing factor of drafting is mostly absent at the slower speeds at which climbing occurs.
Drafting in general favors the shorter rider as they fit more completely into another rider’s slip stream. Another critical aspect of competitive cycling is accelerations, which shorter riders tend to excel at due to increased strength in relation to their mass (once again, square-cube law). Accelerations can occur when coming out of a turn, as riders jockey for position, or from attempts to ‘drop’ competitors. Two more advantages for shorter cyclists are aerobic and heat dissipation proficiency.
In all around competitions such as a grand tour, all of these factors come into play, and form an inverted U-shaped height curve. Those who find themselves on the podium tend to be near the peak of this curve.
Despite the many advantages of short stature, there have been some above average height winners of the Tour de France in recent years: 6′1″ Andy Shleck, 6′3″ Bradly Wiggins, and 6′1″ Chris Froome. What these riders have in common is their exceptionally long limbed and lean bodies (just over 150 lbs). The relatively low body mass for better climbing, high surface area for better cooling, low frontal profile for lesser drag, yet long legs for generating power, all play to the cyclist’s advantage. The very tallest riders in cycling must abide by such proportions to the extreme. For example, 6′6″ Johan Van Summeren weighs only 168 lbs.
Beyond the physical aspects of the body, however, success in cycling requires extraordinary perseverance and determination. It is a grueling endurance sport, and only those who can ride through pain, train relentlessly to perfect technique, and maintain consistency stand a chance. It is this that explains why some cyclists, despite the obvious disadvantage of their size, such as Johan Van Summeren, have somehow found their way onto the podium.
- Swain DP, Coast JR, Clifford PS, Milliken MC, Stray-Gundersen J. Influence of body size on oxygen consumption during bicycling. J Appl Physiol. 1987;62.