Want to build better legs? You know, tough, durable legs that can tackle anything without getting beat up? Sprinkle in some downhills.

Most runners know that hills are good for them (even if they avoid them!), but they are usually thinking about the uphill being the hard part. If you are doing traditional hill repeats, you run hard uphill and jog the downs as recovery.

But if you really want to build better legs, try doing that in reverse.

Why downhill? Isn't that the easy part?

The thing that I love most about downhill running is that it's fun!  You can fly down a hill with less effort and at faster speeds than you can on flat and it really makes you feel like a little kid without a care in the world.  Your lungs do not have to work as hard and your legs can turnover just about as quick as they can.

As it gets tougher and tougher to qualify for Boston, more and more people seek out downhill races because they think they will have a better chance if they can just fly downhill.  While for many people, that is the case, for others, a downhill course can absolutely wreck them.

And if you're a trail runner, hills are just part of the deal. Many trail runners are actually SLOWER on technical downhills because they lack the confidence that rock-solid quads and good technique give you.

There is a technique to running downhill and definitely some things you want to keep in mind about training and racing downhill.  If you do it right, you can take advantage of gravity's free speed, but if you do it wrong, you can send much stronger shock waves up your legs and burn out your quads, risking both performance and injury. 

So how do you do it?

 Just like when running uphill, you want to have a slight lean forward at the hips to take advantage of the downhill. Don’t overdo the lean, you only need a slight tilt to benefit from gravity. 

Now this is going to feel really awkward at first.  Our natural human instinct is to lean back into the hill to prevent ourselves from tumbling all the way down and crashing.  But what happens when we lean back, is that our foot goes forward ahead of us, and often the heel hits the ground first.  There's nothing inherently wrong with heel striking, but if your foot hits the ground before your center of gravity crosses above it, you are adding pounds more stress to your legs.  And not only that, you are braking with every step, giving up the free energy that the downhill is supposed to give you.  So you are increasing your chance for injury as well as slowing yourself down at the same time.  Not a great idea.

But if you lean down the hill slightly, gravity will pull you forward so you will have to work less.  So if you think of downhill running as controlled falling, you can capture that energy and use it for speed.  Again, we have an instinct to avoid falling so this might feel a little strange and even scary on certain hills, but the more you practice it, the better at it you'll get.

Remember: lean forward to avoid braking and breaking!

So what do you do with your arms? 

For a road race or another smooth surface, you want to keep your arms relaxed and only slightly moving forward and back. You don't want to flail them out to the sides because it wastes energy.

On the other hand for a technical trail race where you are maneuvering over roots and rocks and uneven surfaces, using your arms for balance can be a very good thing.  The little energy that it costs to use your arms can be a small investment if it prevents a tumble down the trail.

On the roads where you are not expecting any obstacles, keep your head up and your eyes looking forward instead of down.  This is also something that might not feel natural right away because when we are afraid of falling, we want to look down.  Don't do that.  Look ahead to where you are going, not where your feet are.

On trails of course, you will need to shorten your gaze to avoid obstacles , but you still should be looking several feet ahead of you and not down at your feet.

Getting good at the forward lean takes practice but eventually you will build confidence.  Confidently leaning forward when your instinct is to pull back will not be automatic so practice it every time you go downhill.

What about your feet?

You'll want to land with your foot  right beneath your torso or as close as you can. Depending on the grade of the downhill, you might not quite land underneath your torso, and that's okay if it's not too much.  In general, the steeper the grade, the more likely your foot is to land out in front.   

Again, when you extend your leg too much ahead of the rest of your body, you are more likely to land on your heel, which will act like a breaking motion. Focus on landing towards your midfoot to maintain speed while staying in control.

You will notice that your stride length naturally extends when running downhill. However, you should not try to consciously increase your stride length.   Let the grade of the hill do this naturally for you.

Aren't downhills bad for my knees?

Running hard downhill is eccentric muscle training, meaning the work is done as the muscle is lengthening. No other form of running will do this.

Downhill running increases your quadricep and hamstring strength and stiffness, improves running efficiency, and has been shown to reduce delayed-onset muscle syndrome.

And of course, it makes you a better downhill runner!

If you are a healthy runner that introduces downhills gradually and recovers adequately, you are not risking your knees, but are in fact strengthening them. If you do have current or recurring knee issues, be even more gentle with downhills, but ultimately, the strength gains from downhill running helps support your knees.

Downhill Repeats Workout

• Choose a hill that is fairly steep, but not technical if you are on trails. It should be something that you feel comfortable running down quickly and the grade will depend on your ability.
• After you've run your usual warm up mile or two, jog up the hill for about a minute or so. Remember the up is the rest and the down is the work, so be sure to jog the ups. At the top, stop and catch your breath for as long as you need to, usually 30-60 seconds.
• Then get ready to rip! Fly down that hill as fast as you feel comfortable using great technique. The length of your hill is determined by your ability, but most runners should take 30-45 seconds or so to get down.
• Stand at the bottom for 30-60 seconds to catch your breath and then repeat 6-10 times, depending on your ability.
• Run your usual cool down of a mile or two.

If you've never done this kind of downhill training, be warned: THIS IS EXTREMELY TOUGH AND YOU WILL BE SORE! so go easier than you feel necessary at first. You can add these in once a month at first and then progress up to every other week.

What's the best way to race downhill?

The answer is a bit course dependent.

Let's look at the iconic downhill course, the Boston Marathon.  Boston is a net downhill course, dropping 447 feet/136m over the course of the full 42.2K distance.  But it actually has the slowest time of all the majors if you look at elite finishing times.  One of the main reasons for that is the series of uphills at the 20 mile mark, as well as the relatively high chance of fighting a headwind.  But nonetheless, just because it's a net downhill, does not mean it's fast.

The general strategy for running Boston is to avoid getting too carried away with your speed on the first 20 miles of descent, because if you burn up your quads, Heartbreak Hill will feel like Mount Everest.  And even if you manage to crest the hills intact, the final 6 mile downhill of race will feel like you are running on legs made of wet spaghetti.

Increasing in popularity are the really dramatic downhill races such as the REVEL series of races in the Western US.  You are shuttled to the top of a mountain and basically roll down the hill to the finish line.  These are fun and they are fast, but if you have not properly toughened up your quads with lots of downhills in training, you might find these types of races to be exceptionally painful.

Besides training on downhills what else can you do? 

Toughen up those quads in the gym.  Wall sits are great, where you press your back into the wall as you squat (it looks like you are sitting in a chair, without the chair).  Take your wall sit up a notch by holding a weight and/or lifting your heels into a calf raise. Lunges of all kinds, both with weights and without, elevated on a step and on the ground, are all good quad strengtheners.

Another tip, especially if you don't have a lot of downhills to train on is to use a downhill treadmill or elevate the back of a TM to make a decline.  Be sure to get the okay with your gym before you do this if you don't have a TM at home!  This way, you can train on the decline without ever going outside.

Just remember that a little goes a long way.  You don't need all your runs to be on a downhill to get good at them.  Two or three times a week is usually plenty.  As you get closer to the race, you'll want to make sure that you do at least two point to point long runs on a decline if you can.

With practice and good technique, you can learn to run and race downhill safely and effectively and who knows?  You might even have some fun.