I have become increasingly aware of a surprising, if not ironic fact about my transitions from bike to run. While it does feel as though my legs are heavy and sluggish when starting the run, I have found that I am a MUCH faster runner coming off the bike than I am during a “normal” run. This is not simply because I am sufficiently warmed up, because the reality is that after 40 miles or so, my legs are tired; far beyond warmed up.
This little phenomenon prompted me to search around on the web and I haven’t found anyone else praising the biking gods for making them a faster runner. What I have found is a substantial debate around the significance of keeping your bike cadence and run cadence the same during a triathlon. The argument is that by keeping them the same, you avoid muscle confusion. Another view is that it doesn’t really matter if they stay the same, but the cadence does tend to be same simply because of muscle memory; if you ride at 90 rpms, your legs simply continue on their merry way at 90 rpm once you start running. The third view is that cadence doesn’t mean squat as long as your comfortable.
My own personal opinion is a combination of 1 and 2. First, I believe that you tend to run at the same rpm as you do on the bike due to muscle memory. If your legs are pumping away at a certain pace for hours, it’s only natural that they will continue to work at that pace even though the mode of movement is completely different. But I also believe you should keep your bike and run cadences the same – but not to avoid muscle confusion. Instead, they should be the same because the optimal rpm (for me, anyway) is the same on both the bike and on the run. As someone that is currently working on adjusting his stride to be shorter and thus creating less stress on his body, I have an optimal running cadence of 90-95. On the bike, I find my most efficient riding is at 95 rpm. Very close.
What’s interesting and a bit frustrating for me is that when I go out for a run workout (not as part of a brick workout or a triathlon), I really struggle to get my cadence up to 88, let alone 90-95. My pace at that cadence tends to be anywhere from 7:30 – 8:30 min/mile. After a mile or two, I can get it up to 90, but it’s not easy. When I come off the bike, my natural stride is pumping away at 93 or 94 rpms – and my pace is from 6:30-7:00 min/mile. And what’s crazy, is that I can keep that up - for awhile. There is NO way I could start from nothing and work up to a 6:30 min/mile.
I guess I am not making an argument so much as a personal observation which is this: I am a much faster and more efficient runner coming off the bike as compared to my standard run. Am I the only one that experiences this?