Avoiding the downhill disaster
Every runner knows that hills are hard. We plan races according to how hilly the terrain is; we do hill workouts to gain strength and make sure we can handle the hills on race day. But almost always, when we talk about hills, we’re referring to the uphills. And this is no surprise, considering that running uphill causes a noticeable discomfort. Running downhill, on the other hand, often feels easier than running on flat ground and comes as a welcome reward for cresting a murderous uphill.
But something many new runners don’t know — indeed, I didn’t learn it until my fourth marathon — is that downhills can be just as dangerous to your finish time as the uphills. Go bombing down a mile-long decline during a race or fail to train on downhills, and your marathon could take a sudden turn for the worse when your quads quit on you before it’s time to collapse and get a beer.
So why is downhilling so rough on your muscles? When you fly down a hill, your stride naturally lengthens. The result, when you land, is a tremendous load that your quadriceps muscle must stabilize. The required muscle contraction is eccentric, meaning the muscle lengthens rather than shortens, so that the tissue tears and quickly weakens even though you don’t feel like you’re working all that hard.
Fatigue from downhill running is of particular concern on trails, where one often encounters climbs and descents far steeper than those found on roads. A common race strategy is to walk the steepest uphills and save the energy for the downhills, where control is of even more importance than it is on roads. Hills are so steep that the limiting factor to your downhill speed is often not how fast you can run, but how fast you can safely run, so the temptation to barrel down the hill is even greater.
According to a recent article titled “All Downhill From Here” in Trail Runner magazine, there are a few things you can do to make downhill running easier. First, add downhill sessions to your training schedule, just as you do with uphills. In traditional hill workouts, you run hard up the hill and rest on the way down before repeating. On downhill days you’ll want the emphasis to be on the downhill section, so save your energy on the way up and focus on form on the way down. There’s no need to consciously lengthen your stride more than happens naturally, and focusing on a fast turnover will help to lessen the shocks to your quads.
As for handling downhills on race day, it’s all about sticking to your pace. Shoot for an even intensity throughout the race. Just as you slow down on the climbs, you should speed up slightly on downhills, but don’t let your adrenaline get the best of you. Be familiar with the downhill speed you can handle and don’t let yourself exceed that speed during the race, and you’ll save yourself from the Jell-O legs that we’ve all experienced plenty, but have hardly ever blamed on the downhills.