Minimal Shoe and Barefoot Running

Lieberman's Theories on Barefoot Running

Harvard professor Dan Lieberman is an evolutionary biologist best known for his theories about barefoot running. He states that out of the one million people that will run a marathon next year and of those that run for either recreational or exercise purposes, a large proportion (between 20-90% of these individuals) will develop repetitive stress injuries from running. Lieberman’s background in evolutionary biology has lead him to the hypothesis that ‘some of the running injuries that people get … come from a mismatch between the way we use our bodies and the way our bodies are adapted’. Anatomically Lieberman states that humans are ‘loaded…with special features…some of them important for walking but some important for running, for example our long Achilles tendon…or the gluteus Maximus…’ a significant point he raises is the ‘importance of proprioception’ referring to the sensory information that humans receive from bare feet, allowing for quick reaction to changes in terrain or substrate, as he states ‘even putting a sock on somebody’s foot decreases your dynamic stability considerably. So we’re much more stable when barefoot’.

Heel Strike vs. Mid-Foot Strike

One of the basic findings in Lieberman’s research is that while habitual barefoot runners strike with the mid-foot, most shod runners, heel strike. Lieberman highlights that the heel striking action causes a ‘rapid exchange of momentum between your body and the ground. This causes a collision peak, called and impact peak and if you were barefoot, that force can rise between one and two-and-a-half times your body mass.’ He states that heel striking does have its benefits including, a reduced requirement of calf strength, and allows runners to over stride which is an easier way of going faster, however his research has shown that barefoot forefoot strikers have increased compliance in their legs, and a decreased loading rate, he also believes that there is a possibility that forefront striking leads to better performance, as he commented ‘I don’t know if there’s a single distance record held in any event by a heel striker.’

Running Form and Injury Prevention

Lieberman suggests that whatever the running style there are two important principals that good runners have in common. The first is that they lean forward. The second is they have a high stride frequency. Lieberman acknowledges the fundamental importance of understanding how running form relates to injury. Meta-analyses, injury rates fluctuate between 20-90 percent, Lieberman states that, ‘there’s no decline in running injury rates over the last 30,40 years…and that’s the problem. Somehow, the methods we’re using to try and treat…and prevent running injuries, somehow don’t seem to be working effectively.’ He added that there is no evidence to support that prescription shoes reduce injury rates. Lieberman reiterates his opinion that the reduction of running injuries relies far more on form than footwear. 

Form Over Footwear: The Role of Technique in Injury Prevention

Studies by colleague Irene Davis have led to suggest that the rate and active loading impact peaks may have a significant influence on injury however this is disputed by other researchers and continues to be debated. Leiberman states that whilst barefoot forefoot striking may reduce incidence of back pain, stress fractures, shin splints and other injuries, its striking increases loading on the Achilles which could lead to higher rates of some tendonopathies. Lieberman belief is that, ‘Its all about form. It’s a skill.’ Thus regardless of footwear, correct technique when running is essential for the prevention of running related injuries.