The good news is hills are leg strengtheners and character builders, the bad news is they slow you down during races. Although you run slower uphill and faster downhill they don't counterbalance; if everything else is equal, your times on hilly courses are slower than on level courses of the same distance. Let's see why that happens, and how you can use hills to improve your running.

The Science of Hill Running
Best racing times come with an even pace; in technical language, you should run for constant energy output. In turn, this means you need to keep your oxygen intake the same, and keep your lactate level constant. Lactate is a by-product of anaerobic effort, and when it builds up to high levels in your muscles they tire and slow down. The shorter the distance the faster you run, then you run with more anaerobic effort which increases your lactate build-up.

Uphill running adds to the problem. It takes more energy, so you need more oxygen. If you were running as fast as you could on the level, your breathing and heart rates were already close to their limit, so the amount of extra oxygen you can make available is relatively small. The result is that uphill you go into oxygen debt. You use more anaerobic energy, and your lactate level goes up.

Jeffery Staab, Ph.D., and colleagues at Springfield College in Massachusetts, help us understand why this messes up our overall times on hilly runs.

Fifty miles a week men who run better than 38 minutes for 10K ran three "treadmill courses." One was flat, the others hilly; one with uphill first, and the other with downhill first. For race atmosphere, the runners rested the day before each trial, ran in racing shoes, received mile splits, and ran for prizes. Each "race" was a 30 minute run. It didn't matter whether the uphill section came before the downhill section or the other way around, the hilly runs were slower.

When you run uphill you slow as your body tries to maintain constant energy output. In spite of the uphill slowdown, Staab found oxygen uptake and heartrate still increased, and blood lactate increased considerably. Pace stayed slower than usual when the men ran flat sections following uphill running, and blood lactate stayed high. This means there was a period of forced recovery from the anaerobic cost of running uphill. Slowdown on flat sections was greatest when they followed an uphill which was later in the "race."

On downhill sections oxygen uptake went down. This means the runners couldn't run fast enough on downhill sections to maintain constant energy output. This could be due to residual fatigue from the uphill effort, or, perhaps the runners couldn't handle faster running for mechanical reasons. The overall result was a race pace about 2.6% slower on the hilly trials. This is equivalent to adding 58 seconds to a 37 minute 10K. Staab concluded, "...On hilly courses large amounts of lactate accumulate on uphill which remain relatively high on subsequent stages of the race. The slower performance time on hilly versus flat race courses may be due to the higher energy cost of the uphill, which is not compensated for on the downhill."

Strategy for Hill Racing
Let's think about this. If you include hills, intervals, fartleks, and spells at 5K race pace in your training, you will push up your anaerobic threshold, the point at which you'll build up lactate above normal levels. Then you can run faster and still stay in your aerobic zone. This won't avoid the problems described in Staab's study, because you're a competitive animal you'll take advantage of your extended aerobic zone to race uphill even faster. This will leave you with the same problem, you still won't compensate on downhill sections.

There seems to be only one answer: race slower than usual uphill. This will hold down lactate build-up and let you recover more quickly and run faster downhill. How fast you can run downhill may then depend mainly on how fast you can move your legs and keep your balance, because there are biomechanical limitations to downhill running. Editorial Board Member Paul Taylor, D.P.M., says "Downhill running tends to cause over- striding at some point, which leads to increased use of braking muscles to keep you form falling on your face. Also, running too fast downhill is a common cause of shinsplints." If you could run a little slower uphill and then run faster downhill, overall, your race times on hilly courses could improve.

Can you handle this strategy? When you're well trained and feel ready to peak, do you really have the will power to hold back on the first uphill? It goes against the grain, doesn't it? All your competitive instincts tell you to attack that hill with a surge. Also, when you really burn that first hill doesn't the sense of feeling good carry over during the rest of the course, and keep you flying when folks who struggled on that hill are beginning to die?

The science is neat, but don't underestimate the psychology. For all the ingenuity of Staab's experiments, they were still a bunch of guys fighting a treadmill, with tubes in their mouths and catheters in their arms. Somehow that doesn't add up to racing in a crowd of pumped up runners, on solid roads, under an open sky, with live spectators. Surely that's worth as much as a few milligrams of lactate saved?

But on second thoughts, nearly a minute off a 10K by running slower uphill in order to run faster downhill; is it really possible? Can you afford not to give it a try? Suppose someone else tries it first: and it works? You'd better go for it!

The Art of Hill Training
To race faster on hills you must train on hills. First, you can include hill intervals in your workouts. You need a hill of 100 to 200 yards, not too steep, so you can run uphill with good form. A grade of not more than 10% works fine. Warmup for a couple of miles, then surge up your hill at about 10K race pace, and jog down for recovery. Run four repeats first time, increase by one a week until you complete eight to 12 hills. Marathoners can run longer hills, up to about a mile. Run one at first at about marathon race pace, and increase one a week until you can handle four repeats.

For added value on hills use springing and bounding drills. The value of these techniques arises from the principle that your feet act like springs when you run; they store energy when the muscles and tendons are compressed and release energy when they expand. British scientist R. McNeill Alexander, F.R.S., measured the recoil energy of human feet to prove they behaved like springs. Alexander described feet as like pogo sticks which compress their springs on landing and recoil to throw the jumper back into the air. He found the human arch on impact returns 80% of its stored energy. By comparison, running shoes of the 1980s returned 55% to 69% of stored energy on impact. Alexander's research is the foundation of the design of modern tracks, built to aid energy transfer and help athletes run faster.

You can't change the mechanical properties of the surfaces you run on, but you can improve the elastic properties of your feet and legs by springing and bounding. Push off with a more forceful ankle motion and toe-off, push higher and with a longer stride than normal, and land on your midfoot, or even toes, not on your heel.

In the 1960s Arthur Lydiard, coach of numerous outstanding runners, such as Peter Snell, who earned Olympic medals and broke world records, included springing drills in his programs. In 1978, Lydiard wrote about hill springing. "Since ankle flexibility and power is important you should work on this training all the time. Bouncing up gentle slopes on your toes will gradually develop power and flexion in the ankles. It will also stretch other leg muscles and tendons." Approach these drills with caution, though, because Editorial Board Member Pete Pfitzinger reminds us "Lydiard's men were often injured during this training phase."

A more recent adaptation of hill springing is in Galloway's Book on Running. "Pick a moderate hill. Bounce off one foot and leap into the air lifting lead knee. Hang in the air until the last second. Very quickly bring the leading leg down for a landing, and spring off with the leg almost straight. Here's where the ankle has to do its work. Never let the push-off leg be perfectly straight. Keep the knee slightly bent to avoid spraining the weak and slow-healing muscles behind the knee. Keep a short stride length, just work on floating and maintaining form."

According to Galloway, bounding is a variation performed on level or slightly sloping surfaces. Differences from hill springing are: "Lift knees higher. Take longer strides. On each step you are driving with greater power, extending your stride and developing your calf muscles."

David Martin and Sebastian Coe (Training Distance Runners) also recommend similar techniques for short hill runs. "An exaggerated running style is required to maximize speed, as this spreads the energy requirement to large muscle groups other than the legs. Once gain, the vigorous arm action, a quick and powerful knee lift by action of the hip flexors, and the powerful toe-off from each driving leg are all important elements for sudden dramatic pace changing..."

Even though you're an experienced runner, treat springing and bounding like any other new exercise, because although they will help you to deliver more energy in your running, they take more energy to perform, too. Begin with only 20 to 50 feet and concentrate on form; use your arms to drive your legs. As you become familiar with these techniques, slowly build until you can keep them up for 100 yards. If you run long one day a week, and perform speedwork once a week, add a little springing and bounding to your low intensity runs for variety. Your racing should improve after a few weeks.

All these techniques aim at strengthening your uphill running. Taylor points out that since usually running downhill you don't make up the time you lost running uphill, you should train to improve your downhill running, too. Try some downhill sections once a week in which you try to run smoothly at increasing pace, just short of the speed which brings you to the point of losing your balance. With practice, you should be able to maintain balance at faster paces. Editorial Board Member Jerry Lynch, Ed.D., suggests shorter strides with quicker turnover will help develop better downhill technique.

Above all, you need a positive mental attitude toward hills. If you dread hills you will not run your best on them. Lynch, advises "Turn hate into love." You must affirm that you love hills for the boost they will put into your races. Love hills because they make you a better runner, and they give you a psychological boost over other runners who still hate them. Affirm over and over, I love hills, I love hills..." says lynch. See how you'll set off a chain reaction. You'll love hills and you'll improve your hill running. Improvement brings self-esteem and enjoyment which will reinforce your love of hill running. Then your race times will improve, which will make you happy and also reinforce your love for hills. Then you'll work out even harder on the hills...

I bet you can't wait to put this article down, tie on your shoes, and hit those hills.

Just about all the studies on hill running involve performance and racing. How about hills compared to level running for people interested only in health and fitness. Clearly those who run hills will run a little slower overall, and their oxygen uptake will vary uphill and downhill. But the work performed during running is determined mainly by bodyweight multiplied by distance, the calories burned will be similar, which means the health benefits will be similar.

There might be a slight improvement in oxygen uptake and leg muscle strength in hill runners, but for slow running you wouldn't expect this to be significant. At slow pace there's no reason to expect any increase in injury risk as long as you don't make sudden changes in mileage or speed.

Copyright, The American Running Association.

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