It was around four to six million years ago when humans first evolved to walk upright. We continued to evolve into superb long-distance walkers and runners, made possible by our arched feet, long achilles tendon, and ability to cool through sweating. And surprisingly, for most of human history this long distance travel was done barefoot.

Some evidence suggests footwear emerged around 30,000 years ago. But it wasn’t until about 100 years ago that fashionable footwear was reported to be altering the shape of the foot. Since the 1970s, cushioned running shoes have become synonymous with exercise.

But a growing body of evidence shows running shoes might actually be doing us more harm than good. Our latest review suggests that wearing shoes changes the way we run and weakens the foot in a way that can contribute to many common sports injuries.

Previously, our team revealed that we can still run barefoot, especially if we start young. We found that not only could children in New Zealand aged 12-19 run sprint and middle-distance races barefoot, we also found the prevalence of pain in the lower limbs (knees, ankles, and feet) was relatively low compared with children of similar ages from other countries. Other research has also shown differences in foot structure and function in barefoot and shoe-wearing populations.

These findings prompted us to conduct a global review of running injuries in men and women. We found that between 35 and 50% of runners were injured at any one time. These numbers could be considered high – especially for a species adapted to long-distance running. The most common injuries were to the knees, shins, ankles and feet. Most of these injuries were mainly to bone or connective tissue, whose primary function is to help transmit force from the muscles to allow movement.

Our latest review explored how humans ran before using shoes, and how shoes change the way we run. We found that when the foot comes into contact with the ground, the skin, ligaments, tendons and nerves of the foot feed a rich source of information to the brain and spinal cord about the exact position of our foot, including tension, stretch and pressure. The quality of this information allows the precise control of muscles to move our joints into a position that absorbs impact and limits damage.

Enter footwear

The first mass-marketed cushioned running shoe was manufactured in the 1970s and advertised as footwear that could prevent running injuries. Surprisingly, this narrative even found its way into the scientific literature. In the 1980s, “better running shoes” were suggested as a reason for the reduced incidence of Achilles tendinopathy in one study and “poor shoes” were suggested as a risk factor for stress fractures in another study.

Our review suggests that footwear reduces the quality of information being sent to the brain and spinal cord, leading to more blunt running mechanics. Shoes allow runners to land with a more upright body position and an extended leg, leading to excessive braking forces. These running mechanics seem to play a role in some of the most common running injuries.

Long-term everyday use of footwear also leads to a weaker foot and often, a collapsed arch. When we start running in shoes, our foot isn’t adapted to cope with these mechanics.

But this damage might be reversible. Interestingly, one study found that foot muscle size and strength were found to increase after eight weeks of walking in a minimalist shoe. This is because removing the cushioned heel and arch support made the foot’s muscle work harder.

Balance activities are also recommended to improve proprioception, which is our awareness of our body’s position and movements. This type of training aims to prevent or repair injuries. Using equipment like a wobble board will create more unstable or less predictable conditions under foot, which builds lower limb stability and foot strength.

But the simplest and perhaps most specific form of proprioceptive training for runners is to take off their shoes and walk or run. In fact, barefoot runners appear to report fewer knee injuries and less heel pain compared to runners who use shoes.

However, barefoot runners do report more calf and achilles tendon injuries. This suggests that people who transition too quickly to barefoot activities may overload their muscles and tendons. This might be because barefoot runners usually have a shorter stride and more flexed hip, knee and ankle. They also tend to run more on the tip of their toes.

Read more: Children should spend more time barefoot to encourage a healthier foot structure

Although ditching your running shoes might not work for everyone, if you want to give barefoot running a try, the best advice is to walk before you run. A minimalist shoe might be a good first step if walking or running in extreme temperatures or where sharp objects may be common. Although minimalist shoes aren’t the same as being barefoot, the mechanics runners and walkers use in them are very similar to when barefoot – and dramatically different to when in shoes.

Running injuries are caused by many factors, such as age, previous injuries, body mass index, and sudden changes in training volume – so shoes might not be wholly to blame. And while shoes are relatively new to our species, so are our sedentary lifestyles.

It’s likely that these factors might also make humans less conditioned to move how they did millions of years ago. This suggests a combination of getting more active, walking or running barefoot more often, and other conditioning exercises may help prevent further injuries in the future.

Peter Francis, Lecturer in Sport, Exercise and Rehabilitation Science, Leeds Beckett University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

The human species is one of the most efficient terrestrial animals. We adapted to run on dry riverbeds and grasslands, but development of modern society has strained the evolutionary process.

Footwear was initially introduced to protect the soles of the feet or provide traction or warmth. But as society has changed, footwear’s role has adapted to provide cushioning for the hard cobblestones or pavement, broad protection for industrial tasks, and more recently, as a fashion accessory and performance optimiser.

A return to barefoot running has emerged as a subculture in recreational running, its devotees pointing to reduced injury rates and a more “natural” running experience.

Perhaps the biggest impetus for the trend was Christopher McDougall’s 2010 best-selling book, Born to Run. While based on the story of Mexico’s Tarahumara Indians who run ultra-endurance distances barefoot or in tyre-tread sandals, McDougall also concludes that running shoes have done little to prevent injuries over the past 40 years.

Apart from the aficionados writing in the popular literature, a key proponent of barefoot running is Harvard University evolutionary biologist Dr Daniel Leiberman. He argues that habitually barefoot runners land more on the mid-foot or forefoot, which reduces the transient shock on contact.

Runners who wear shoes, on the other hand, land more on the heel and rely on the design of the shoe to absorb shock and control the foot during running.

But Leiberman suggests the issue is less about barefoot running being better than shod running and more about how we run.

Running barefoot encourages the runner to cushion the impact of landing by adjusting their running style to land with their toes down. The shock of landing is transmitted largely to the muscles at the back of the leg. As a result, barefoot and minimally shod running appears to reduce the risk of injury because they generate much lower collision forces.

But don’t throw your running shoes away just yet. Barefoot runners must learn to change the way they run: landing more on the mid-foot or forefoot, rather than on the heel. Then the elastic structures within the foot will do the job they were designed to do. And the Achilles tendon and calf muscles will contract eccentrically to cushion this extra load.

For those new to barefoot running, the unaccustomed strain on muscles and tendons can actually lead to injury – exactly what the change to barefoot running was supposed to prevent.

The solution? Start out slowly on a safe surface (grass or sand) to toughen the sole of the foot and allow the soft tissue of the foot and ankle to adapt to the new loading strategy. Alternating running barefoot one day and shod the next will also decrease the risk of injury.

We all have different abilities to learn and to adapt to new skills: some will make the adjustment and thrive as barefoot runners; others will struggle to make the change, particularly if they have irreversible structural problems with their tendons and muscles, caused by decades of wearing sneakers.

Unfortunately, ditching your sneakers isn’t the silver bullet to preventing running injuries.

Peter Milburn, Professor, School of Rehabilitation Sciences, Griffith University

This article is republished from The Conversation under a Creative Commons license. Read the original article.

There’s a growing interest in barefoot running, especially in relation to running long distances. Research articles, opinion pieces, and websites have argued both for and against the efficacy of running without shoes, but few have stressed the importance of a measured transition.

The primary argument for barefoot running is that it encourages the use of more natural biomechanics, which is lost when using traditional footwear.

But it is very important to keep in mind that changes occur to technique when transitioning from shod (wearing shoes) to barefoot running.

Primarily, there is a shift to forefoot/midfoot contact, as opposed to a rearfoot or heel, contact.

Research has found this has performance benefits by showing that faster elite distance runners tended to have forefoot/midfoot contact.

To facilitate this change in foot contact, step length is reduced, and step frequency increased. This means that over a given distance, you will complete more steps of a relatively shorter length when you run with bare feet.

This change of technique is important, as when you remove the cushioning that is built into most running shoes, your running style must change to ensure the shock experienced when landing is reduced.

Research on habitual barefoot runners found shorter step lengths helped reduce the force of impact.

Proprioception and strength of the individual muscles in the feet could also improve with barefoot running.

These muscles act to stabilise the foot during ground contact, a demand that is greatly reduced when running with shoes.

Despite all this, there are some problems associated with barefoot running. When running without shoes, your feet have no protection have against the outside environment.

While this may not be an issue on certain surfaces, such as grass, there may be problems if you’re a trail or urban runner.

It also takes time to adapt to the changes in stress that will be experienced when running under new conditions.

A habitually shod runner will need to adapt to the different stresses experienced during barefoot running.

Several shoe companies are tapping into the barefoot running trend through changes to shoe design.

These shoes are designed to mimic barefoot running – they don’t have the cushioning that’s present in traditional running shoes – while still providing protection from outside elements.

Examples include the Nike Free, New Balance Minimus, Saucony Kinvara, and Vibram FiveFingers. The use of these shoes could serve as a bridge from running with shoes to running barefoot.

Interestingly, all the current research has focused on distance running: no research has analysed barefoot maximal sprinting.

This is significant, as correct sprinting technique should incorporate forefoot contact to help reduce ground contact time and increase step frequency.

Further, if the muscles within the feet are strengthened during barefoot running, they could provide benefits for sprinting, where maximal force output is required.

Here are some useful pointers for barefoot running, especially for those conditioned to running with shoes:

• The duration of your runs should initially be decreased for barefoot sessions – to less than 20 minutes to start – with gradual increases over time.

• Surfaces such as level grass or beach sand would be a good place to start running barefoot.

• A good strategy is to alternate running sessions: run one session in shoes and next barefoot.

Perhaps the most important thing to remember is it’s not necessarily the shoes you wear that cause injury, but rather incorrect running mechanics.

Ensuring that your running gait doesn’t predispose you to injury should be a stronger concern than just considering the type of footwear to be used.

Robert Lockie, Lecturer in Exercise and Sports Science, University of Newcastle

This article is republished from The Conversation under a Creative Commons license. Read the original article.

Humans have gone unshod for millions of years; it is only in the last few centuries that people have started wearing shoes. However, a recent survey shows that shoe wearing among young boys isn’t universal. German children and teenagers spend most of their day in shoes, while about 90% of their South African counterparts go barefoot.

Aside from the obvious climate differences, it is tempting to think that South Africa’s lower economic ranking, compared with Germany’s, is the main reason for the absence of footwear. But this reasoning has been challenged by results from our recent survey.

We gathered information on the footwear habits of 714 boys attending a secondary school in a wealthy part of Auckland, New Zealand. Almost half of the students (45%) spent most of their time barefoot. Many of the students in this study were even willing to run distances of 100 to 3,000 metres on a hard track surface without shoes.

Foot structure

Differences in foot structure between those who have never worn shoes and those who are usually in shoes have been described for over a century. In one seminal 1905 study, Phil Hoffman, warned how putting the fashionable desires of customers over the health of their feet had led to shoe design “that more or less crowds the front of the foot”.

The main developmental result of growing up in shoes appears to be a narrower foot and a lower arch. The result of this is more concentrated pressure at the heel and the ball of the foot during movement.

By contrast, those who grow up barefoot have wider feet and have a more even distribution of pressure towards the outside edge of the foot and across the toes.

Running as nature intended

We don’t know what effect growing up in shoes has on the development of movement skills, or the risk of injury in sport, but logic suggests that growing up barefoot is a good thing.

The heel of the foot is highly sensitive to pain, meaning that when people run barefoot they tend to avoid landing on their heel and instead defer the pressure to the mid and forefoot. This allows a broader surface area to absorb force.

In order to avoid a heel strike, the foot must never be too far in front of the body. As a result, barefoot runners tend to have a shorter stride. A shorter stride needs less leg extension, which is why barefoot runners have greater bend at the knee and a more pointed foot toward the floor. These joint positions allow muscles around the knee to help control landing and allow the ankle to behave in a more spring-like fashion.

The problem with shoes

Covering the heel of the foot reduces the sensation it experiences when coming into contact with the ground. The running shoe, containing a cushioned heel, allows the runner to land on the heel of the foot with an extended leg. This is perhaps why about 75% of runners nowadays are heel strikers.

Running using an extended limb (overstriding) results in force being absorbed through the heel, bony structures and joints, with less assistance from muscle. This may be one of the reasons most running injuries are to structures that are not designed to absorb force (shins, feet and knees). Interestingly, when people remove their shoes, most revert to middle and forefoot striking.

Children and teenagers who grow up mostly barefoot appear strong enough to run quickly and for long distances without shoes. The prevalence of leg pain in the New Zealand students we studied was at the lower end of that reported globally in students of a similar age. This finding, combined with an absence of evidence for the role of shoes in the prevention of injury, makes it seem reasonable to suggest that children should spend as much time as possible barefoot.

Social acceptability is a barrier to barefoot activities in many Western countries, as a result, adults who did not grow up mostly barefoot may not have the same foot structure and leg strength to transition to barefoot activities quickly.

Gradually building time spent walking and running in bare feet is key for people who are new to barefoot activities. The increasing availability of shoes that mimic the structure of the foot (minimalist shoes) and have little cushioning other than to cover the foot, may help people transition to being barefoot. The improving design of these shoes may also help to tackle the issue of social acceptability.

Peter Francis, Director of the Musculoskeletal Science Research Group, Leeds Beckett University

This article is republished from The Conversation under a Creative Commons license. Read the original article.