It seems the benchmark of 180 strides per minute is the accepted threshold in the running community to qualify as an efficient runner. However, based on research and my personal experiences, I challenge whether that is the appropriate threshold to focus on and, to go further, it may be that shortening your stride is detrimental.
There are many studies on this subject such as a Danish study that analyzed the running form and technique of elite 5k and 10k runners. It found that when running speed increases from 10:00/per mile pace to 5.42/per mile pace, stride frequency increased by only 10% while stride length increased by 83%. It wasn’t until runners reached a 4.20/per mile pace that pace increased due to stride frequency (there are other studies that cite similar results when analyzing stride length and stride frequency).
The fear of course is that runners will over-stride. However, this may be over simplifying the problem. My friend Pete Larson has provide video of elite runners at the last Boston marathon and there are quite a few runners that appear to be over-stride, that is, landing in front of the body but let’s think about it further. It’s very difficult, if not impossible, to initially land under the body. Additionally, there’s a different between “landing” and “loading.” The issue does not appear to be so much about landing in front of the body but identifying the point in the stride where the weight loading is occurring which is commonly under the body as your center of gravity passes over your feet and legs (i.e., think of forward momentum). If you over-stride, there would some type of breaking effect, so if you are running smoothly, it’s difficult to over-stride.
I don’t have a problem with 180 steps per minute being a reference point but stride length is often over-looked in the discussion. Many of the best runners that maintain 180 strides per minute or higher, are doing so with an optimal or longer stride. In fact, in another study that analyzed 36 experience male runners with an average 5k time of 18:22, they found the average stride frequency to be 171 on average, but a longer stride length than compared to less experienced or recreational runners (the stride frequency did not increase until the runner’s decided to surge or sprint for a brief time). I see many runners taking baby steps or shuffling which causes fatigue and can interrupt a runner’s natural stride. I find it tiring to shorten my stride.
So a take-away for me is that middle and long distance runners are better off concentrating on increasing stride length and sprinters benefit from increasing both leg turnover and stride length. Based on my personal experiences, lengthening my stride increased by running speed almost effortlessly. Only when I needed to sprint, did an increase in stride frequency become a key factor (so middle/long distance runners still benefit from speed work en ensure they can sprint to the finish line).
HHH
Thanks for the fascinating post! As a relatively new runner at the age of 51 I'm trying to learn to enjoy running after many years of avoiding it and dreading the very idea. I've been getting out about 3 times a week and only logging short distances in the 2 mile range. I've worked my way up in VFF Bikilas, but the big nagging problem I have is my stride rate. I'm constantly way down in the 85-95 steps per minute range! in concentrating on what I'm doing i can easily see myself making the exact mistake you describe of "taking baby steps or shuffling" to shorten my stride and by extension increase my SPM. Clearly I need a new strategy and need to get out and try something new. Thanks for giving me some food for thought!
ReplyDeleteChris