Downhill Sprints CNS theory

Could you use a short hill to ease the CNS drain of a top speed (or near top speed) acceleration? With the aid of gravity wouldn’t a runner be able to reach a higher speed with less effort?

I’ve a “rim” around my track approximately 25 feet tall. We have a hill that we use in our crosscountry course that you can actually run down and be on the top turn of the track. It is fairly steep, about a 30 degree angle, but Could I use that hill to do some of my 30 and 40 meter fly’s?

That sounds a bit too steep.

I don’t know about the CNS factor, but I really liked doing flying runs with the first 20-30m down a slight slope that ends gradually (!) in a flat and running the actual high speed part in the flat. You do not need to waste energy to accelerate in the flat and gain your speed easily running downhill.

I ran 20m fl 0.2s faster than in the flat and concentrated on just “letting my body move” relaxed at high speed and a few weeks later I ran the same times in the flat.

More advanced athletes told me they were barely faster downhill - curius for other “forumites” experiences…

And you might face a higher risk of getting injured - I had to stop, because the surface was too hard (dirt almost as hard as concrete) and I got problems with my ankle…

Especially if the slope is too steep you get a funny feeling reaching the flat part - it’s like running against double gravity…

Use the wind rather than hills for assisted running - safer.

Angle should be VERY shallow. I wouldn’t attempt a 30 degree hill sprint downhill!!

Are you sure it’s 30Degrees? That’s like going off a cliff! The Russians use to talk about hills at 3d uphill and 2.5d downhill.

Just found something on sprinting down hills??? No idea of it Validity???

Secrets of Russian Sprint Training
By: Mark J. Occhipinti, M.S.
Almost every coach is constantly looking for ways to increase the speed of their athletes whether it be for track and field events or organized team sports (Football, basketball, baseball, ice hockey, etc.). Many different methods of speed training are available today, with many of the newest innovations trickling down from our Olympic National Teams. I found a program while working as strength coach in college that has been touched on in the past, that works, and is worth discussion. Over the years the Russians have been innovative in their experimentation with everything from anabolic steroids to pre-selecting elementary children for future athletic careers. I was introduced to the Russian method of sprint training (plyo-metrics) during the early 1980’s and was impressed with the increased performance and reduced stop-watch time of each athlete who trained in this fashion. Today many large colleges and universities use this program along with many professional teams.

Physiology of training for speed

As a coach or athlete it is important to understand that there are only two ways of improving speed:


Many coaches/athletes are mislead by stride length. They believe the stride can be improved in running by “reaching” out further with the lead or front leg. It is the back or “driving leg” that determines the ground you cover in a given amount of time. The greater the leg power, the better the chance of developing a longer stride. This leg power and increased stride can be developed through the traditional weight training, running steps, and running up hills. Stride frequency refers to how fast the legs actually move during the sprint. Genetics determine faster stride frequency in many of the elite athletes,( an example would be Carl Lewis). It is a common belief still today by many coaches that stride frequency cannot be improved with training. I disagree, especially after seeing improvements both personally, and the athletes that I had the opportunity to work with.

The Program

The idea is to train the body beyond its normal capacity which will allow the athlete to get the most our of their training. By prompting your arms and legs to move faster than they can move through normal training, you can achieve your goal in speed training. This is the principle behind downhill training which is part of the plyo-metric philosophy for increasing performance. The best way that I have found to implement the program is over an eight week period. The speed work is performed on Monday, Wednesday, and Friday, while the weight-training days are scheduled for Tuesday, Thursday, and Saturday.

It is important to implement a concentrated program first of warm-up and then flexibility to reduce the chance of injury. All times are recorded on a stop watch and recorded as pre-training times, which also assists in grouping the athletes in 3 to 4 per group based on their personal times in the 40 yard sprint.

Week 1 through 7 the work-out for sprinting remains basically the same, with the work consisting of 12 repetitions of 40 yard sprints. The first week the sprints are run on a flat surface.
During week 2 through 8 a 10 degree downhill slope is introduced, increasing up to a 45 degree downhill slope by week 8. Talk about steep!

Mechanics to Increasing Speed

Downhill sprint training works in the following way: An athlete runs a 4.8 forty yard sprint on a flat surface. Moving to the downhill slope will increase his speed an average of two-tenths of a second
( his speed downhill in the forty yard sprint now has been recorded at 4.6 seconds). The pull of gravity is forcing the athlete to run faster than he would be able to prevent falling. It is important to concentrate of good form and drive while running downhill. During this 8 week training period the athlete will increase his speed as his/her body has adjusted to the fast stride frequency, and the arms and legs can move through space as much greater speeds.

I have increased my 40 yard time two-tenths of a second in 8 weeks and have seen other athletes improve their time by as much as four-tenths of a second after completing this program. The lone draw-back to this type of training: athletes peak very fast employing this type of training. This new level of speed can only be maintained for a short period of time. The average athlete will be able to maintain this speed for approximately eight weeks. This type of training can be cycled two to three times per year for optimum results.

Yeoh! Look out for that one- now it’s 45 degrees! The original Russian stuff was 3d uphill and 2.5d downhill, and, even at that, there was some concern that it might disrupt hip position.
Maybe the theory is to train and THEN do the test 40 down the 45d hill. That would get sesults-once!

The 45-degree angle downhill sprint sounds like a sure winner - for funniest home movies!
It has nothing else to recommend it. (nor does downhill 30-deg, or anything that changes biomechanics and forces the runner into a “breaking” action out of self-preservation.).


Well, in XC we learned to “roll” with the hills… Imagine a ball… rolling down a hill… it speeds up… no breaking action… It gets scary, but my hip position is pretty good on even some of the most extreme hills i’ve ran on. HAH! maybe not.

Okay, maybe “rolling” with the hills isn’t such a good idea, and yah I’m not that great at it, so what? If I can keep from doing the “breaking” action should I use a hill for flying sprints etc? Or should I draw the line further back than the extreme change in form caused by “breaking”? I don’t see why, if only a fraction of my muscles are being activated by a relaxed “gravity” aided acceleration.

If you try that on a 45d hill, you’ll be rolling ok! As a simple test, fold a piece of square paper from corner to corner. Now do you get the idea of how steep 45d is?

even if you were to use downhill drills, would you expect the CNS stress to be less?

and what about the higher load on m. fibres from the eccentric action?


To a certain extent, yes. I do expct CNS stress to be less when using a downhill to aid accel. You’re fighting a significantly less amount of gravity, and it’s not necessary to recruit as many fibers as if you were running on flat ground.

Now, Nik, do raise a good point about a higher load on muscle fibres from eccentric action. A downhill would increase loads on muscles in different patterns than are used during the sprinting action, and it’d probably be easier to get injured while sprinting downhill.

Another thing that just popped into my head, is that if a sprinter isn’t using a hill with a shallow incline, then when they hit flat ground their mechanics are going to change. There is no way to avoid that. That sudden shift in mechanics could also cause injury. But what if you had a hill with a steady change in incline (as most hills are, anyway) that would most assuredly be safer than the 30degree cliff that just jutts out of track, but would it be better than a hill with a overall shallow decline?

(Charlie, I would never dream of using a 45 degree hill for sprints. That’s crazy-talk, man!)

it’s not only a gravity-advantage issue, the way i see it; since fewer fibres might be recruited, as you say, apart from DOMS, these fewer fibres DO have to withstand the inevitably higher speeds, leading to higher CNS stress, i believe

adding the mechanics problems to this, i don’t think it’s worth the risk…


Now that I think about it (Okay, now that you’ve prodded my brain in the right direction), I guess you get the whole “treadmill” effect going on where the sprinter isn’t applying force so much as putting one foot in front of the other too keep up with the ground passing underneat him is a pretty good reason not to do downhill sprints.

But I still have a question about what you said about the CNS. “higher” CNS stress? I don’t think I quite follow. If your referring to downhill mechanics VS flat mechanics, it really doesn’t make much sense to me. If only a fraction of the fibres are being activated, how could they provide higher CNS stress, even if the muscles are taking a higher load than they would normally?

Regarding CNS stress, you might draw an analogy to plyos. Jumping down from a higher box is more stress even though it takes the same effort to drop (none). Kind of like the guy falling from the Empire State Bld who says, as he passes the 40th floor: “So far, so good.”

“so far, so good.” best charlie analogy ever. applause

sorry, i am not functioning at the moment…

are you implying higher, or lower stress?


Higher on landing.

I think the injury risk is way too high running downhill at almost any angle- I was injured in high school running downhill (quite steep)as part of a “fun” XC relay workout. (didn’t know any better- 25 years ago) Even if you found the optimal angle of hill to run down- I’d be concerned about footing- a road would be too hard, a trail or grass hill would surely put ankles at risk, to say nothing of the DOMS. I would also think you’d have to be an experienced runner with great strength and technically sound to be able to maintain proper mechanics while downhill running. There are just better ways to gain speed IMO.