Study shows barefoot running is less efficient
A new study by researchers at the University of Colorado's Locomotion Lab – which has studied the metabolic costs of running and walking for decades – has found that running with shoes is more efficient than running without, using a measure of how much oxygen people consume (and how much carbon dioxide they produce) while running.
“Running in lightweight shoes requires about 3 to 4% less energy than running barefoot,” said Jason Franz, a CU doctoral student who led the study.
The inspiration for the research came from Corbyn Wierzbinski, a CU undergraduate who co-authored the study. Ms Wierzbinski’s boyfriend had recently taken up barefoot running, and she wondered if the advantages she kept hearing about could be scientifically proven. The lab decided to look into one of the more popular assertions.
“We started to see these claims that barefoot running, because you remove the weight of the shoe, is more efficient,” Mr Franz said.
Other scientific studies have shown that the weight of a shoe does impact a runner’s metabolic efficiency. And the CU study confirmed earlier conclusions that the metabolic cost increases by about 1% for every 100 grams of weight added to a runner’s feet.
Mr Franz, Ms Wierzbinski and Rodger Kram, director of the Locomotion Lab, confirmed the findings with the help of 12 male subjects, all of whom were experienced barefoot runners (logging an average of 19 miles a week without substantial shoes) and all of whom landed on the mid-sole of their feet while running with or without shoes.
The researchers also devised a system for adding weights to the top of the runners’ feet when they were barefoot as well as when they ran in shoes. For the study, the participants ran exclusively on a treadmill and they wore thin yoga socks when they ran without shoes. When they ran with shoes, they wore the lightweight Nike Mayfly (the study was not funded or sponsored by Nike or any shoe company) which weighs 150 grams and which has some cushioning but no other “motion control elements,” such as arch support.
When researchers added weight to runners’ feet, their efficiency decreased proportionally to that weight, whether they wore shoes or not.
This means that running without the weight of shoes should be more efficient, but the researchers discovered that this is not the case.
When subjects ran barefoot with an additional 150 grams of weight added to their feet, about the same amount of weight as a Mayfly running shoe, they were 3 to 4% less efficient than when they wore the Mayfly, according to the study, published in the journal Medicine & Science in Sports & Exercise.
The reason why is the subjects of another study at the Locomotion Lab. The research has yet to be completed, but Mr Franz said that he thinks the drop in efficiency may have to do with the need for barefoot runners to compensate when the cushioning of the shoe is removed.
“The barefoot runner needs to cushion against the impact using their muscles,” Mr Franz said. “That requires a little bit of metabolic energy to cushion each stride.”
Despite his study’s findings, Mr Franz said that the research is not an endorsement for or against running barefoot. “We recognise that people choose to run barefoot for a variety of reasons. Some want to connect to their inner caveman; some people think it protects against running-related injury,” he said. “All we’re trying to find out is if there is any scientific basis to those claims that it is more efficient.”
