Barefoot running has obviously become more common in recent years. Indeed, the running media (heavily reliant on advertising revenue from shoe manufacturers) seem to have ended their head-in-the-sand attitude and have printed several articles on the advantages or disadvantages of running barefoot. This is certainly due partly to the big players in running shoe manufacture releasing barefoot oriented, or minimal shoes. Aside from this though is the mounting anecdotal evidence supporting barefoot running. Now, in addition to this anecdotal evidence we have another study seeking to explore the oxygen cost of running barefoot compared to that of wearing shoes.
This recent study, carried out by Hanson, Berg, Deka, Meendering and Ryan (of University of Nebraska and South Dakota University), studied a small group of active runners whilst running on treadmill and over ground with and without shoes at a pace equivalent to 70% vo2max. Specifically, the researchers looked at the oxygen cost of running barefoot or shod. They found that ‘Across the mean of the 2 surface conditions barefoot running was 3.8% more economical than running with shoes‘.
That’s quite a fining, but what does it mean to the average runner? The runner who is not performing a vo2max test on a treadmill? We need to look at the research in a little more detail to learn more. Firstly, this was a small study, just 5 male and 5 female runners were assessed so it is particularly important to look at what type of runners they are; how much they run, their age, and importantly their barefoot running experience. They were all in their mid twenties, ran recreationally at least 16km per week for the past 6 months; 4 of the subjects ran 16-24km per week, 4 ran 24-32km per week and 2 ran 32-40km per week. Two subject ran barefoot most of the time, 2 reported that they had previously run barefoot and the remaining 6 had no barefoot running experience. As mentioned, by oxygen cost, barefoot running was found to be 3.8% more economical. Aside from this, heart rate and perceived physical effort was significantly lower when running barefoot on both the treadmill and overground.
But, why is this? Previous studies have found similar energy saving for the barefoot runner. One study suggested that a contributory factor is that the natural elasticity of the foot is compromised when shoes are worn. Also there is of course a weight saving on the end of each leg and whilst this is seeming very small, when multiplied by each stride it becomes much more significant. There is of course the argument that running barefoot encourages a more efficient style of running or gait. It’s almost impossible to run barefoot with a heel plant and a much more efficient forefoot strike is soon adopted.
There were other useful findings in this study, particularly the difference in energy cost between running on a treadmill compared to running in the open air. It is typical when using treadmills in testing to apply a gradient of 1% to compensate for a lack of wind resistance. The researchers confirmed this figure to be appropriate and reported little difference in energy cost between running on openground and on a treadmill set with 1% incline.
The researchers reported that after the test all but one of the subjects would be likely to try barefoot running in the future.
It could be argued that such a small study group has very little meaning. The researchers acknowledged this, but stated that the differences were so significant that the study was of adequate size to compare running barefoot to shod.
3.8% is a considerable boost to running economy. Of course that doesn’t relate directly to a time saving of the same amount, and even if it did there are other factors to consider before we jump to conclusions about likely time improvements over race distances.
Nevertheless, this recent research and previous studies too demonstrate that our running shoes are costing us more than just money.
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