Thursday, May 17, 2012

Learning to run with a faster cadence

Back in 2009 when I was ran my first marathon and then started thinking I could ramp up my speed, I ran into all kinds of AT problems. Eventually to solve the problem I learned to keep a shorter stride, no over-striding, and a midfoot strike. To do this and not slow down you need a higher cadence.

Since I'm a data nerd, to help with that I bought the little cadence sensor that works with the Garmin(s). Here's a plot of some of my cadences vs pace for 90 days of running back in 2009:



 Here's  the same kind of plot, but from 90 days prior to now:


My 9 minute cadence has gone from 82.9 to 88.3 steps /min, a 6.1% increase in cadence.  The slope has gone from 1.65 cad per min/mile to 2.06. This means for each 2.0 step/min increase in cadence, I pick up a minute per mile in pace.  


Essentially, I have a faster cadence at any pace, and I use cadence improvements to get more of my speed when I increase my pace that I did  before.


A lot of speed does come from stride lengthening but keeping the cadence up i think reduces the chances for injury. In addition, having an efficient long stride AND the ability to a fast stride gives you more ways extract all the energy out of your muscles in a marathon.


I think a faster stride also increases running economy (the energy cost of running). Running with a slow, bounding stride means you are asking your leg muscles to store the elastic energy of rebound in your muscles for a long time.


Muscles are wet sloppy bio-goop, not metal. They don't store energy well...if you want to get out the energy  you put in you need to do it quickly before is dissipates as heat. Hence the evolution of drills like 100-ups and short fast strides that harvest the rebound energy as snappy as possible. Elite runners are in the air all the time and have very very short ground contact times!


YMMV, but I feel if you want to avoid overstriding or other biomechanical problems a cadence sensor to give you feedback and to keep you honest might help. 



7 comments:

  1. I've been thinking of getting a clip-on metronome to help with maintaining a faster and more consistent stride.

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    1. that would work if you also are tracking your pace...don't want to just end up running faster with that higher cadence!

      ie. you need some idea of a pace @ cadence you are at now so you can up the cadence at the same pace.

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  2. I'm very interested in your cadence data. as I mentioned in my last post, I got a foot pod for my Garmin that tracks that. So far, it reports my cadence around 81. What I would like to study is if you run a fixed pace and run half the distance at 80 strides, and the other half at 90 strides, what does the heart rate do. If running economy improves with shorter strides, shouldn't heart rate go down at the higher stride rate?

    Eventually, I'll work more on my stride rate. I've done it before and it seemed to work until I blamed it for a pulled hamstring.

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  3. I don't track any cadence data, but you have me thinking about getting the foot pod now.
    Usually ma cadence work is just trying to increase turnover in minute-long segments, while counting.
    Have you done anything specifically to increase your cadence- or is this just a general trend toward better running economy? I am always looking for new drills. :)

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    1. Hi Raina,
      sorry for the slow reply. Yes, I use proprioceptive cues to help with a short fast stride....I imagine a glass wall right in front of me and a glass ceiling right above me...

      Basically keeps me from overstriding and bouncing up and down too much. 8)

      I also do 'fast feet' drills, 'high knees' and the other more normal drills.

      HTH!
      -paul

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  4. I seem to be around 80 to 85 most of the time. I am slow, though. I can't seem to break 10. Actualy, I my last half marathon I only got 10:45 average. I am trying to lean at the ankles. The seems to help, but it is an uncomfortable position for me to hold for very long.

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What do you think about all this? Please leave me a comment! 8)