It has been a consistent theme of this blog that I think my pace is improving since I switched to minimalist and barefoot running. Well, I think there is now enough data to back it up. I've been using the Nike + iPod system for a long time, with a couple disruptions (having lost my iPod, etc.). The slowgeek.com site has some great graphs for looking at the Nike + iPod data. So, what is the verdict?
I have logged 2000 kilometers since 2006, in 305 runs. The last couple of years, I haven't been very fast. I purchased my Vibram Fivefingers KSO shoes on April 15th (6 weeks ago today, as I write this). In the 16 runs I've done since then (not counting a handfull of barefoot runs, which are not logged and are significantly slower) my pace has improved dramatically. At first, some people said it was probably enthusiasm for my new gear, and simply psychological. That may well be, but I seem to be getting more enthusiastic as time goes on. I've logged 16 runs since then: 126 kilometers. Take a look at the above image, which is a snip from my Pace over Time graph. That is quite a jump and it perfectly coincides with buying the VFFs. If it's simply that I'm excited about new gear I find it surprising that I've maintained that enthusiasm over the 16 runs, and that my excitement seems to be increasing. I think something else is going on.
Another thought I've had, and that others have echoed, is that my pace is increasing because I'm running more. The data doesn't back that up either. In this image from my monthly runs graph the light red is 2009 and the dark red is 2010. In 2009 I logged nearly twice as many miles in April, and almost as many in May. But check out the Pace over Time graph above. I'm a full minute per kilometer faster now. What gives? There isn't a backlog of months of strong training this year either. I hardly ran at all this Winter.
In the short amount of distance since I took up minimalist running, it can't be all fitness improvements. Sure, I think there are benefits to barefoot running that improve the muscles in your feet and calves. But I can't see how suddenly after a regular amount of training I could see my pace jump up a minute per kilometer. I think these improvements are around increased efficiency in my gait. I've always read that the best way to improve your pace was to increase your turnover and shorten your stride. You see it in races. Several times I've been huffing and puffing up some hill, fighting the good fight, and some person comes around and pulls away doing the marathon shuffle: little quick steps, not lifting their feet high, quick turnover. I've worked on that in the past, counting footfalls per minute and trying to increase my turnover, and I think that is some of how I was so much faster in 2005/2006 (that and working out with the Santa Cruz Track Club). But with the Vibrams and barefoot running this kind of gait just comes naturally. I don't have to think about it.
The improvements I've seen have required no real changes to my training patterns, and that boggles my mind. I'm excited by the prospect of how fast I could be if I applied myself. I feel like if I applied myself (actual speedwork, hills, consistant distance and a long run every week) I could actually close in on my 44 minute 10k PR and my 1:47 half marathon PR. I doubt I could do it for the Summerfast 10k in July, but for the first time in years I think I can run that fast again in the future.
Maybe my running will peak in my 40s instead of my 30s. If it does, I hope I'll be sitting around in 10 years saying "maybe my running will peak in my 50s instead of my 40s!" Hell, at this rate I'll qualify for the Boston Marathon before I'm 60. I'll be a shoe-in in my 80s!
Here is to a bright future as a mid-pack runner.