"In cycling, practical experience still outruns science."

Bradley Wiggins’ amazing Tour de France and Olympic gold medal wins has inspired us to take a break from swimming posts to dive back into John Forester’s Effective Cycling. Here’s an excerpt from Forester’s “The Physiology and Technique of Hard Riding” chapter:

Abilities of Cyclists

Cycling is by far the most energetic activity you can undertake. Other activities may produce more force, as does weight lifting, or more muscle power over a short period, as do track sprinting or most swimming events, but there is nothing that approaches the long-term, high-power demands of cycling. In these events, the cyclist is working as hard as possible in the most efficient way for many hours at a stretch—for 4 hours for a 100-mile race, for 12 or 24 hours for long-distance events, and even for several days in the longest events, interrupted only by the amount of sleep that the cyclist chooses. Stage races may require only 6 hours a day, but the biggest has 22 racing days in a month.

The contrast with many other activities becomes more apparent when cycles of motion are considered. Many weight trainers consider 20 or 30 repetitions adequate. A long swimming race may require 500 strokes. A marathon run requires about 30,000 paces. The 200-mile ride, which is probably cycling’s equivalent to the marathon, requires 50,000 pedal revolutions. Even the century ride, which cyclists of all types complete, requires 25,000 revolutions. The world’s record of 507 miles in a day probably required more than 100,000 revolutions.

These demands for energy, and the ability of first-class cyclists to meet them, exceed the boundaries of our physiological knowledge—at least as it is published in scientific journals. We do not have sufficiently accurate explanations of exercise physiology to enable us to recommend training practices for hard riding that are based on laboratory knowledge. Rather, we are still at the stage where the known capabilities, techniques, and experiences of hard riders are the base data for extending our present physiological theories of short-term exercise into the realm of long-term, high-power exercise. As a result of this inadequate knowledge, when current exercise physiology has been applied to engineering design for cyclists, such as in the design of bikeways, the results have been contrary to experience. One ludicrous result is the published criterion for bikeway grades, which states that the highest hill that most cyclists can climb is 34 feet high. Cyclists should be skeptical of all recommendations that have been made by exercise physiologists, for these are generally based on scientific theories that do not apply to the conditions of cycling. Scientists typically continue to apply generally accepted theories to particular situations, even when the data for one situation (cycling, in this case) refute the theory. In cycling, practical experience still outruns science.

Known Facts about High-Performance Cycling

Cyclists are able to exceed 25 mph on the road for up to 8 hours, and to exceed 20 mph for up to 24 hours. Competitors in these events, like sporting cyclists in general, ride with cadences between 90 and 110 rpm. Cyclists eat and drink while cycling. Cyclists who take early leads in massed-start events (as opposed to unpaced time-trial events) rarely are in position to contend in the final sprint. These are the known facts that must be explained by any legitimate theory of cycling.