The subtitle to this article should be “without falling or hurting your knees”, because there comes a point in every runner’s life where one of these unceremoniously happens to you. Whether in a race or a training run, the added benefit of ascent is the speed and freedom of the descent. The problem is harnessing body mechanics and gravity into the perfect symphony for speed and not disaster.
Let us discuss mechanics. When running downhill, the initial instinct may be to attempt to decelerate the body by leaning back with the trunk, and striking the ground heel first. These two actions paired together increase the ground reaction forces through the legs significantly. Additionally, by leaning back, increased pressure is put into the low back, which can lead to a back injury as well.
Conversely, flying downhill willy nilly and out of control can lead to strain in the knees and low back as well, not to mention the prospect of a fall which can lead to face planting (add insult to injury if there are witnesses).
So how then, do we safely get down hill simultaneously clipping time off our pace and running safely? First and foremost, utilize your core musculature. Draw your belly button in towards your spine, and bend forward slightly with your whole trunk, flexing at the hips. The lean should be approximately 10 degrees, and your line of vision should fall 4-5 feet in front of your feet, not on the feet themselves. This will prevent you from leaning too far over your feet (again, face planting =bad).
The turnover of running stride should increase slightly as a product of shortening of the stride length. This will promote midfoot strike and help decrease the likelihood of heavy heel first striking down the hill, thus decreasing force through the legs and low back. Some runners benefit from self talk as they negotiate difficult terrain. A mantra to remain “light like a feather” on your feet is a helpful one.
Finally, arms should be utilized to maintain balance. Arm swing may increase a bit in swing excursion front to back, though they should not drift away from the body from side to side unless you are actually falling.
“Beyond mountains there are mountains”- Haitian proverb
Make your day great,