Running downhill should be the easy bit, right? You can be a little faster with less effort and it feels great, but downhill running can actually cause a great deal of stress on the body. It’s a bit like eating cake batter or looking at the sun on a cold day – running downhill feels great at first, but after a while, you can feel that you might be doing yourself some damage.
I learnt this in my first 100km trail race, long before I ever knew about 2XU compression socks. The long downhills eventually caught up with me, as my feet slammed into the toe-ends of the shoes with every step. By the end of the race, several toenails were coming out… backwards. Quadriceps, knees, ankles and feet are all at risk, but if you take care with your technique you can protect your body and learn to pick up speed efficiently so you can eat up some easy kilometres.
CUT THE JARRING IMPACT
Avoid locking out the knees and overstriding (landing your foot far ahead of your hips) and heel-striking. All these things prevent you from dissipating the impact forces that come from you hitting the ground.
TAKE SMALL STEPS
The greater the slope and the more slippery or unstable the surface, the smaller your steps should be. This will give you greater stability and make it easier to have faster, lighter contact with the ground.
STEP LIGHT, STEP FAST
Many runners have a tendency to turn off and tune out when they go downhill, and their feet clunk down heavily with enough ground contact time for ants to pack the kids into the mud caked on your shoes and use it as a caravan. Light, fast steps help with speed and your feet will land with less pressure so that your leg muscles and the soft tissue around your knees won’t have to go into ‘braking’ mode – which is where the damage occurs.
USE YOUR CORE TO KEEP THE TORSO STILL
Just as sprinters use their core more, you have to consciously activate the muscles through your trunk due to the higher speeds. This will reduce the excessive movement around joints that can lead to injury. This is especially important for trail runners carrying a pack – your balance can easily be thrown out going downhill if you’re not holding yourself solid through the core.
ADJUST TO THE SURFACE
Is the ground surface slippery? Do you slide when you land? (e.g. on gravel). Is the ground stable or are there loose rocks for your feet to roll on? Be prepared to change how you run depending on all these things. On a surface with rocks or potential obstacles, you will need to lift your knees in an exaggerated fashion. On a smooth surface (e.g. a dry sealed road or footpath), you can keep your feet very close to the ground to minimise impact.
ADJUST TO THE SLOPE
The greater the slope, the shorter your stride, the lighter and quicker your ground contact and, beyond a certain point, it will be best to lean back a little.
USE YOUR ARMS
On rough, unstable or slippery surfaces, keep the elbow and arms low and out a little from the body to stabilise you and so they’re in a good position to break a fall or grab onto trees or boulders for balance. When the surface is good, keep your feet low and get a big arm swing – arms bent at about 90 degrees, swinging your fist right back behind your hip, arms and elbows close to the sides of your body. This is a great way to pick up speed without pushing harder through the legs.
LOOK WELL AHEAD OF YOU
Avoid looking at the ground just in front of your feet. You’re travelling faster, so you need more warning of any obstacle ahead so you can avoid braking or even decelerating too quickly – both cause a lot of stress on the body.
USE YOUR TOES
On particularly long or steep slopes, use your toes to ‘grip’ into the sole of your shoe – like you are trying to pick a pen off the floor in the underside of your toes. This avoids the toes shunting forward in the shoe as your foot hits the ground, plus it will create more stability on landing, which will give you a more confident step and help protect the ankles and knees.