Elite ultrarunner Guillaume Millet ran his first Ultra Trail du Mont-Blanc (UTMB) race in Chamonix, France, in 2004. He had trained hard for the uphills—runners gain 30,000 feet of elevation over the 100-mile course—but failed to prepare for the plunging downhills, including a nearly 2,375-foot drop between miles 45 and 48. Ultimately, it was the relentless pressure of the descents that wore him down the most during the race, leading Millet to a 28-hour, 35-minute finish, nearly 7.5 hours longer than the winner.
The next year, Millet altered his training to include a focus on downhills, repeatedly riding a ski lift to the top of a mountain and running down the slopes. He was rewarded with a fourth-place finish, clocking in at 23:45:24. “Definitely, that [downhill training] was the main difference between the two races,” says Millet.
Downhill running puts a heavy load on your legs, including higher chances of muscle damage and other injuries. Careful and specific preparation is a must for any runner attempting a course with a considerable downhill component, be it a trail race like the UTMB or a road race like the Boston Marathon.
We asked Millet and Megan Lund Lizotte, a San Diego–based running coach and a sub-three-hour finisher at this year’s Boston Marathon, for their best tips on training up to go down.
The Downhill Difference
Running up an incline versus down an incline is practically an entirely different sport, Millet says. “If you run downhill and uphill, this is as different as cycling and running, for me.”
When you head uphill, your muscles work hardest when they shorten as you straighten your leg and push off the ground—this is known as a concentric contraction. Heading down, on the other hand, involves almost exclusively eccentric contractions. Your leg muscles engage when they’re in a lengthened and stretched position as you bend your knee before it hits the ground and absorbs the impact, making them more prone to microtears and damage. That’s why courses with early downhill sections like Boston hit your quads hard, causing delayed fatigue mid-race or increased soreness in the days after.
What’s more, your center of mass shifts as you descend, instinctively causing you to lean backward and try to slow yourself down. But hitting the brakes too hard actually worsens the impact on your muscles, joints, and bones as you essentially fight your body weight on the way down. In fact, downhill running increases impact forces by 54 percent compared to level running, according to a study in the Journal of Biomechanics—a surefire way to wear out your muscles quickly.
“Naturally your body wants to protect itself against that gravitational pull, so it tends to hesitate,” Lizotte says. Running downhill well, she says, means “managing that hesitation so you’re still moving fluidly and efficiently, but not at a pace where you’re completely out of control.”
Refine Your Technique
Tweaking your form makes a big difference in reducing downhill’s detrimental effects, Millet says. Try to think of your movement down the slope like a controlled fall. Take short, fast steps and turn over your legs quickly. Focus on leaning slightly forward at the waist so your feet stay below your center of mass. Envision keeping your nose directly over your pubic bone and in alignment with your belly button, Lizotte recommends. This also prevents you from sticking your head out, a position that creates extra tension in your neck.
Practice Pays Off
Protect your body by taking advantage of the repeated bout effect—the idea that even brief exposure to eccentric contractions helps your muscles resist damage and soreness the next time around, Millet says. In short, that means that you can specifically train for downhill running and see improvements in your performance as well as better injury protection as a result.
If you’re completely new to downhill running and strength training, any sort of lower-body weight training you do will build strength and therefore resilience in your legs as you tackle descents. But you’ll get the most from moves such as single-leg deadlifts, hamstring curls, and calf raises done with an emphasis on the eccentric or lengthening portion of the movement by slowing your motion during that phase of the lift.
Best of all, though, is just to get out there and move down some hills. Start with hiking a descending route wearing a backpack, Millet says. Then progress to doing some easy runs on hillier courses, focusing on your downhill technique. Once you’re comfortable there, add a couple minutes of race-pace running on the descent to familiarize yourself with how the effort will feel during your event, Lizotte says. Another option: Work in a few 10-to-15-second downhill sprints at top speed, which will improve your technical skills on downhills and make race pace feel easy by comparison, Millet says.
Given the extra beating your muscles take during downhill work, it’s critical to leave plenty of days in between downhill days to recover. Begin with one workout every three weeks, gradually progressing as your body adapts and soreness decreases.
Even at your peak, once a week or so is probably sufficient to maximize the gains of downhill training without creating excess injury risk, Lizotte says. “Interjecting it throughout the training plan will help. It doesn’t take a lot,” she says. If you don’t live in a hilly spot, you can supplement your training with fast intervals and drills like butt kicks and high knees on flat land, Lizotte says. These types of workouts will improve your turnover and build quad strength even without having downhills for practice.