Running downhill....

I think it somewhere in between, just before going completely out of control, landing soft, staying relaxed and using your arms for balance is key, oh and practice practice practice. I try to think of it as floating when trying to go downhill fast.

I do think it is more difficult for bigger runners than smaller one's just due to the higher center of gravity. The other side of the coin is with the longer legs and gravity working for you have a better opportuinty to kick their A$$ compete with the little speedsters downhill.

We used to race down Squaw Peak in Phoenix, a jagged hiking trail about 1.25 miles, I couldn't imagine doing that now.

I'd be interested to know what the chi and evolution folks say about it though.

http://www.mamashealth.com/run/downhill.asp

You definately don't want to hit the brakes.  As you noted, you will really be taking a big impact every time you land (and going slower to boot).  Downhill you want to really make sure you are getting quick turnover and keeping your feet landing underneath your body (not out in front). 

If you generally run at a low cadence, it will be very difficult to run downhill without forcefully hitting the brakes.  But hitting the brakes and running slower will actually take more out of your legs.  Working on strides on a slight downhill is a great way to get a feeling for this and improve your ability to turnover at higher cadences.

Edit:  Also, your stride length will increase.  But it should not lengthen by reaching out in front of your body with your leg.  You will simply be in the air longer after push-off as you take advantage of the hill.  And keep your upper body steady--no twising at the hips or swinging the arms across your midsection.  Form becomes more important going downhill in my view.

Sheesh, I've written a lot about this lately to people.  I'm not a clyde but I am 195 lbs. so I know about impact on downhills.  The key for me is this:

 "it feels like my stride lengthens too much"

Don't let it!  Focus hard on form.  Think of yourself as rolling like a bicycle on the downhill.  Your feet just tap the ground in order to keep your balance (and your face off the asphalt).  tap tap tap like a machine gun.  Keep your stride as short as you can.  In reality it will lengthen, but it feels like you are taking shorter steps than normal.  Stay on your toes/balls of feet.  Hold your upper body tight (solid, not painfully locked) and in rhythm.   Think of it like swimming form.  You can do it if you perfect the form.  Smooth is fast.

Bob Glover talks about this in "The Competitive Runner's Handbook".  He said the best way is to stay perpendicular to the surface (much like you are when running on a flat), and focus on maintaining your form.  And he's a big guy, too.  Your stride length will increase automatically, since you're spending a little more time in the air.  But other than that, you let the downhill do the work for you.  You shouldn't feel out of control unless you're flopping around a lot, or it's a very steep hill.  If the hill is extremely steep, he recommends walking down it, and resuming your run at the bottom.

If you're hitting hard on your heels, you're leaning back too much.  Also, don't exaggerate the arm swing, it's counterproductive (unlike going uphill). 

As Scout said, the accepted norm in the running world seems to be to make sure no matter which direction you are going (up or down) it is best to stick to keeping your body 90 degrees to the running surface.  I guess the premise is that it keeps your body in alignment so your form doesn't go to crap.

I'm going to need to ensure that my downhill running is smooth and consistent come April ..... people have said that little race I'm doing can make or break you with the downhill work in the first half .......

Same as Rick and scout said, keep your body as if you were running on a flat surface. DO NOT lean backwards because this will cause you to break every step and don’t lean too much forward because that will through you out of balance.  You can basically either let yourself go and in order to keep your regular cadence (i.e. 180) you can lengthen your stride. Since you’ll be going down faster you still should be landing underneath your hips. Or you can keep your stride length the same but you’ll have to increase your cadence (i.e. 186-190). Again you’ll let your self go running a bit faster but the quicker smother steps should make you feel you are ‘rolling’ down the hill…

Learn to use gravity going downhill.

The way I look at it is; my form should stay good, I shouldn't feel additional force on my heels on my foot strike, and my heart rate shouldn't go down.  

As others have stated, it's a great way to pass people and pick up a few places in a race. 

For me this was key.  Don't be deluded into thinking its less work than running on flats.  For me it IS harder and my HR and breathing do become more labored on a very steep downhill.  The point is the return on investment is WAY more than just running on flats so it is worth the extra effort.  I don't even feel like I'm trying to move my legs now, it just happens.  Once you nail it right on a few STEEP downhills it will be a lot easier to recapture the form on rolling downhills.  Those can really pay off too.

Going back to the OP, you already know 95% of what was suggested here, Chris, it just doesn't sound like you have the feel for it yet.  Find a pretty steep hill and try some hill repeats incorporating the tips people have suggested.  Something is sure to click with you and even if it doesn't the UPhill running will surely benefit you.  Of course, stay safe, I'm not suggesting you careen wildly out of control until the feeling hits you.  That's how I did it.

LOL, yeah, my running partner and I found a grassy hill, he said that's where I should practice so if I do a face plant it's no big deal (well, less of a big deal).  Great.  Haven't done that since I was 12.

Thanks for all the great advice here.  Sounds like leaning forward so I am perpendicular and higher cadence are the two key things.  Something to work on.

Here is an interesting artile on the subject.

http://www.mamashealth.com/run/downhill.asp