I've long suspected that my running cadence (the number of steps taken per minute of running) is a little slow. I've read in a few places that a faster cadence can help you reduce injuries, most critically, in the Jack Daniels running guide. Daniels suggests that most runners do best with a cadence of 180, which seems quite fast to me.
During today's run, I decided to try checking my cadence, so about 3 miles in, I looked at my watch and started counting every other step. I figured I'd count to 30 and see how long it takes -- a cadence of 180 would correspond to a 30-count every 20 seconds (30 counts * 2 paces per count * 3 20-second intervals in a minute). It took 22 seconds, quite consistently. That's 180 paces every 66 seconds, or 163 paces per minute. Slow!
Next step: See what it's like to run at a faster cadence. So about halfway through Mile 5, I tried to maintain my pace but run at a cadence of 180. It definitely felt harder, but I could see that it also felt as if I was lighter on my feet. A check back at my GPS record of the run suggests that I actually did speed up at this point, then slowed a bit for the first half of Mile 6. Finally I picked up the pace at the end of the run, doing the last .34 miles at a 7:30 pace, compared to roughly an 8:15 pace for the rest of the run. This felt quite strange indeed; usually I try to lengthen my stride to run faster. I was doing that, of course, but I still had to take shorter strides than I was used to, going that pace.
In the spirit of Jack Daniels, I will try keeping this up for a week or so and see how it feels. I'll probably write it up over on Science-Based Running when I'm done, so stay tuned for that.
Details of today's workout are below: