Downhill Running (Down Dipsea Stairs Analysis)

The (single) dipsea race started on a bet placed in 1904 as to which person could make it from the train depot in mill valley to the Seadrift Inn first, and they thought it was so fun that it was organized into a race in 1905 and has continued every year since. Then in 1970 the DSE running club had the bright idea to run it as an out-and-back and the double dipsea was born. Then, tired of there being so few ultra-trail-runs around, some ultra-runner decided to host various ultra-fun-runs, and John Medinger invited people out to try doing the dipsea 4 times (barely qualifying it as an ultra-marathon) and the quad-dipsea had its first running on in 1983.

Links for further info about dipsea races:

http://www.dipsea.org/history.php

http://brazenracing.com/r/doubledipsea.html

http://www.quad-dipsea.com/records-and-history.html

 

    I had heard about the Dipsea races for a number of years, and had been particularly curious about the Quad. So, on November 2015 I went out to Stinson beach to spectate the race. I had a few friends running and wanted to cheer them on, and I also thought it could be a cool opportunity to observe the entire field of runners go past me a few times. Due to a family engagement  later in the day, I only had time to see the leaders run past me twice: once downhill and once uphill.

    On the downhill section I was able to get some slow-mo footage of the eventual first-place runner (Alex Varner), as well as several of the guys trailing him a few minutes behind. In my initial perusal of the footage, I noticed a marked difference in the form of the lead runner running down-stairs from how the guys behind him ran down the same set of stairs.

    When I found out he finished the race over 30 minutes ahead of 2nd place and set a new course record, I tried taking some time to analyze a very small piece of this record-setting performance.

    In my first impressions, Varner’s motions seemed more “springy,” so I thought to compare their ground contact times. It turns out most of them had very similar ground contacts time, and varner’s wasn’t even the shortest.

    Then I noticed that the other runners’ quad-muscles seemed engaged for much longer, as they appeared to lower themselves down to the step below, whereas Varner’s quads seemed to fire quickly and forcefully to both slow the downward movement and redirect/transfer some of it to forward movement, and then falling down to the next step in a more parabolic arc, instead of the steady lowering motion. So his motion through space looked a little more like this:

 

And the runners behind him looked a little more like this:

You might think a more wavy line of motion would be less economical than a straight line, but I think when you put it together with the picture of the leg and think about gravity, you see that these quick and forceful muscle contractions varner makes also seemed to lead to a straighter and stiffer leg at the point the leg is taking the most force, which are the dots on the diagrams.

 

  I know, these aren’t really to scale...but you get the idea. Varner, at this point, imagine his center of gravity continuing along the line. His stance leg wouldn’t bend as much, making it a springier motion and less of a lowering

I know, these aren’t really to scale...but you get the idea. Varner, at this point, imagine his center of gravity continuing along the line. His stance leg wouldn’t bend as much, making it a springier motion and less of a lowering

  The other runners, continuing along the line, bend their stance leg much more to lower their weight more before their stance leg comes off the ground.

The other runners, continuing along the line, bend their stance leg much more to lower their weight more before their stance leg comes off the ground.

 

Varner’s ankle also seemed to spring back much quicker than the others, making use of the elastic recoil of the achilles to transfer the energy forward up instead of just using it to absorb impact. And you also see his swing leg held up longer, whereas with the other runners, as soon as they hit, you see their swing leg drop to try to take some of the force. So it seems like Varner is transferring the force more, using elastic energy, whereas the other runners are just trying to absorb and deaden the force of landing, therefore moving forward slower, and using more of an eccentric muscle motion (potentially causing more muscle damage).

You can see the footage in this video:


So then, I see two questions to be asked:

  1. Are the same qualities of Varner’s downhill running common for elite runners running at his level, while usually not being true of slower runners?
  2. If so, how do you get to the point of being able to run this way?

 

Hopefully I can answer this in the future, with a little more exploration.

Would love your comments/feedback! What is your experience in trying to run faster downhill?