For new readers

To get an idea of what I'm trying to do and why I think it's possible, check out the following entries, they'll help get you up to speed.

Friday, November 20, 2009

Tricks of the trade #1 - running cadence

In the next few blogs I'm going to endeavor to impart some wisdom for those interested.  I can't take credit for any of these 'tricks' - all I can do is vouch for their effectiveness on a personal level.  Some of these i've arrived at independently, but have since seen in print elsewhere.  i'll try to give credit and/or links to further information whenever i can.

Trick number 1:  Develop a high (90+) running cadence.  The ideal running cadence is one in which your right foot will strike the ground at least 90 times every minute.  This is a far higher turnover rate than most 'recreational' runners will find that they are using.  I first tried this out after reading Joe Friel's "triathlon training bible" right after i moved to New Zealand back in the fall of 2005.  I trained myself over about 6 weeks to have a 'default' cadence at about this level and have never looked back.  The theory behind this notion is sound and well explained in Friel's book for those who are interested - but in a nutshell the idea is that when running, the ability to change cadence is far more limited than the ability to change stride length.  When transitioning from a 'long run' pace to a sprint, for example, a typical athlete might double stride length while only increasing cadence by 10%.  A high base cadence allows for greater speed.  Something I don't recall Friel mentioning, however, that i feel plays an important role as well, is the idea of a minimum stride length.  It's natural for someone attempting to train the body to take more steps every minute to shorten each individual step.  But once steps get too short, they feel un-natural.  I found that just in adapting to a higher cadence my 'slow run' pace had increased by more than 30 seconds per mile - simply because i couldn't comfortably take short enough steps at the new cadence to run my old pace.

Since then, my 'warm-up pace' has dropped more than a minute per mile and running at 8 minutes per mile feels positively like a stroll (at least for the first 10 or 15 miles).  I've also noticed benefits during triathlon - the shuffle step that many athletes face for some time right after the bike ends up being a lot 'faster' when you have 90+ of them as opposed to lets say 75 every minute.  When I did my olympic tri this fall I was surprised at the end to find out that my pace for the run had been under 7 min/mile, despite the fact that my quads were cramping within the first two minutes.  The cramping lasted for the duration and served as a major limiter to my speed because it kept me from stretching out my stride - but this mattered less as i was able to maintain my accustomed high leg turnover rate.

As alluded to above, a further benefit of making the switch to a higher cadence (in addition to a faster 'base' pace) is an overall greater potential as a runner.  Just as there's a lower limit to stride length, there's a higher limit as well.  a runner who goes 75 steps per minute at max stride is simply not going to be as fast as one who's taking 20% more steps of the same length in that time.  90-95 seems to be the optimum cadence, however, as higher cadences are apparently physically harder to maintain for long distances and don't allow for effective adaptation by your body.

No comments:

Post a Comment