Many runners view climbs as the hardest sections of a hilly race, but ultramarathoner and coach David Roche says descents can create problems later. Although running downhill may reduce cardiovascular strain, it places repeated braking stress on the quadriceps, which must control the body’s momentum.
That stress comes from eccentric contractions, in which muscles produce force while lengthening. A long descent can expose the legs to thousands of these contractions, potentially causing soreness and reducing strength in the closing stages of a marathon or ultramarathon. Roche describes downhill running as a way to prepare the muscles for the demands that often emerge late in endurance events.
The approach is part of Roche’s coaching strategy for Jess McClain, who finished second in the New York City Marathon in 2:24:42 after passing defending champion Hellen Obiri near the finish. Roche also applies the method in his own ultramarathon training and racing. He is a two-time winner and course-record holder at the Life Time Leadville 100, where he ran 15:12:30.
Repeated exposure to downhill running can make the legs more tolerant of the damage and soreness associated with eccentric loading. Research cited in the original report found that recreational runners showed less soreness, a smaller reduction in maximal force and less disruption to their running mechanics when they repeated a steep downhill treadmill run after a three-week interval.
Roche’s preferred session is an easy long run that includes faster downhill sections. He recommends that experienced marathon and ultramarathon runners cover about 16 miles on a hilly route at an overall effort of 3 to 4 on a perceived-exertion scale. Each descent should be run faster than goal race pace, while the flatter or uphill sections are used for easy zone 2 running.
For example, a runner whose marathon effort is around 5 to 6 RPE could run the descents at 6 to 7 RPE, or approximately 20 to 30 seconds per mile faster than marathon pace. Roche suggests choosing descents that are at least as steep as those expected in the target race.
The full 16-mile workout is intended for experienced athletes, but the same principle can be adapted by shortening the run. Roche recommends beginning with one such session per week and adjusting according to recovery; he uses variations of the workout twice weekly in his own training.
The objective is not to leave the quadriceps exhausted after every session. Early workouts may cause noticeable soreness, but consistent, appropriately managed exposure should make the legs less affected by similar descents. That can help runners preserve their strength, mechanics and pace when fatigue becomes decisive near the finish.
Sources: Runner's World.