Harvard University researchers have published a new study in the journal Nature that suggests runners who run barefoot put less stress on the body than runners who wear regular footwear. Running without any footwear encourages the use of a different set of muscles and creates a different gait, which works to prevent repeated, heavy impacts between the feet and the ground.
Researchers analyzed the foot strikes and running strides of runners in the United States and Kenya — where many people have ran barefoot since childhood — using scales, 3-D motion analysis and high-speed cameras. The runners ran at least 12.4 miles per week.
Results showed that barefoot runners were less prone to injuries because they landed on their forefoot and mid-foot, adjusting their leg and foot movements so that they landed more gently on the ground. Modern running shoes with cushioned heels encourage runners to land on the back of their feet. This increases impact on the hips and knees, thereby increasing the likelihood of tibial stress fractures and plantar fasciitis.
“People who don’t wear shoes when they run have an astonishingly different stride. By landing on the middle or front of the foot, barefoot runners have almost no impact collision, much less than most shoe runners generate when they heel strike,” Harvard professor of human evolutionary biology, Daniel Lieberman said.
Lieberman also mentioned that the pronounced arch of the human foot shows human beings are built for long distance running.
“Humans have engaged in endurance running for millions of years, but the modern running shoe was not invented until the 1970s,” Lieberman said.
Cushioned heels mean that a typical runner is pounding the ground heavily at the rate of approximately 1,000 collisions per mile.
Although running without footwear works in testing, it is not advisable on littered streets. Running barefoot, or with minimal shoes, requires different muscles, and runners should transition to little or no footwear slowly.