By Art Horne

Art Horne, MEd, ATC, CSCS, is Strength & Conditioning Coach and Coordinator of Care for men's basketball at Northeastern University, and is currently serving as the Interim Director of Sport Performance. He can be reached at: a.horne@neu.edu.

At the 1960 Summer Olympics in Rome, Ethiopian runner Abebe Bikila earned worldwide fame by winning the marathon with a world-record time of 2:15:16. The attention focused not just on his remarkable feat, but on his remarkable feet--Bikila completed the marathon without wearing shoes or socks.

Some would say that event catapulted the concept of barefoot training into mainstream consciousness. But in reality, athletes around the world trained barefoot in various ways long before Bikila's accomplishment--in fact, you might argue that barefoot training is as old as athletics itself. Barefoot training advocates argue that "shod" (shoe-wearing) athletes miss out on many benefits, ranging from proprioception and motor development to recruitment of important muscles that remain underutilized and practically dormant inside rigid, restrictive modern footwear.

There is very little research providing clear answers on how best to implement barefoot work into today's training strategies. But as an athletic trainer and strength coach who has employed barefoot training with basketball players at Northeastern University for several years, I firmly believe it's well worth the time investment. In this article, I'll explain the concepts behind barefoot training, outline how I use it with my athletes, and discuss the benefits I've seen from having athletes bare their soles during workouts.

THEORY BEFORE PRACTICE
Anyone who has walked barefoot on a beach or grassy field can grasp the theory behind barefoot training and its athletic benefits. By letting the foot return to its primitive state, in which it must grip the earth to produce efficient movement, you can feel the engagement of intrinsic muscles of the toes, midfoot, heel, and ankle--muscles that receive little opportunity for strengthening in our shoes-required world.

The idea behind barefoot training is that developing these muscles improves foot and ankle function, while also providing benefits up the entire kinetic chain. Barefoot proponents point to increased proprioception related to the movement of the feet and ankles in time and space, lower impact forces due to reduced heel strike, higher efficiency in running as measured by lower oxygen consumption, and an increase in bone density throughout the foot and ankle.

Humans' relationship with shoes is a surprisingly complex one, involving both physical and psychological elements. For example, in a 1997 study, researchers had subjects repeatedly step onto and off of a box, each time landing on a pad made of material commonly found in shoe insoles. The material was the same each time, but the authors used different terms to describe the landing pad, and found that participants landed with greatest impact forces when stepping down onto surfaces described with words like "advanced technology" and "used in the most expensive sneakers."

The authors noted the natural human tendency "to be less cautious when using new devices of unknown benefit because of overly positive attitudes associated with new technology and novel devices." If that's true, it may mean today's athletes, who wear more and more advanced footwear and often receive custom tape jobs before each practice and competition, pay less attention than ever to the fundamentals of foot movement and function, possibly harming their performance and increasing their risk for injury. Barefoot training can help reverse those practices.

Consider a more specific example: High-top sneakers with stiff soles are worn almost universally in basketball, and many athletes wear ankle braces or tape underneath them, even for workouts. This practically ensures a weak and dormant foot and ankle complex. Kinematic data suggests that the hallux (big toe) requires 20 degrees of extension and the ankle needs around 20 degrees of dorsiflexion to allow for normal forward motion. Both those movement dimensions are commonly limited by basketball shoes, tape, and braces.

In addition, modern sneakers are usually built with some form of "air cells" or other shock absorbers or supports that raise the heel above its normal resting elevation during standing, planting, and running. For many athletes, this effect contributes to an adaptive shortening of the gastroc/soleus complex and Achilles tendon over time.

On the advice of our podiatrist, we have actually made lateral cuts to the bottom of many of our basketball players' shoes. The cuts extend from one side of the forefoot to the other through the full-length fiberglass insert, directly under the first metacarpophalangeal (MP) joint, basically running across the ball of the foot to alleviate manufactured stiffness and allow for normal big toe extension. We started doing this after several complaints of Achilles tendon pain and anterior knee pain, both of which were alleviated after normal foot motion was restored. Increasing natural foot mobility can also help athletes improve their movement mechanics.

FREE THE FOOT
When athletes perform activities such as dynamic warmup and movement prep with bare feet, they recruit the muscles of their feet and ankles and experience feedback and proprioception in the plantar surface of the foot. At Northeastern, we strongly believe this leads to better positional sense and may contribute to injury prevention and performance enhancement. For those reasons, we have implemented year-round strategies for our men's basketball players to promote the normal motion of the athletes' feet, toes, and ankles.

During evaluations at the beginning of the year, each player undergoes goniometric testing of the ankle, knee, and hip, traditional movement screening (including jumping and landing measures), and an examination of their feet for existing pathologies or mechanical challenges. This is essential, because certain foot-related conditions can make barefoot training counterproductive and even dangerous.

For example, athletes with excessively high arches are excluded from our barefoot work, because most physicians agree that high-arched feet require support to prevent excessive plantar stress and decrease injury risk. In addition, we exclude athletes who have experienced a stress fracture or other serious injury, or have had surgery on the foot or ankle (such as fixation of the navicular bone). To let these players' feet strike the ground repetitively without support during barefoot training would produce injury risks that outweigh any potential benefits.

Some believe that excessive pronators must have firm support from custom orthotics during all activities, but it's been my experience that these athletes do very well in a progressive barefoot program. In fact, I've found that symptoms such as anterior knee pain typically seen in pronators are often resolved when barefoot work is added to their overall training plan. Nonetheless, it's always best to consult a physician, preferably a podiatrist, if you have doubts about the safety of barefoot training for a particular athlete.

BARE ESSENTIALS
Before beginning our barefoot program, we hold an educational session to introduce the athletes to this strategy and explain what they should expect. We tell them it's normal to feel some residual foot soreness after training in bare feet, especially if they've never trained this way before.

However, we note that if the soreness lasts for more than a day, if it's accompanied by sharp or shooting pain, or if it leads to sudden knee or back pain, they should see us for an evaluation, which might lead us to discontinue their barefoot program. These symptoms may indicate an unresolved previous injury, such as a stress reaction or fracture.

For those with normal soreness, we recommend general soft tissue work, such as plantar fascia rolls on a tennis or field hockey ball and basic warmup activities such as ankle mobility drills, static gastroc/soleus stretching, and general dynamic movement patterns. We tell them their foot muscles have been dormant for years in their shoes, so this new engagement and mobilization will be fatiguing--but it shouldn't be seriously painful. If it is, we want to know right away so we can determine the cause.

One of the first priorities when implementing barefoot training is to find a workspace with the right type of surface. Synthetic turf is the best choice, and we are fortunate at Northeastern to have two indoor surfaces (a field house and a turf area located in our weightroom). Since much of the benefit of barefoot training comes from athletes' ability to use their foot muscles to "grip" the ground and feel feedback from a soft ground-foot interface, synthetic turf is far superior to a gym floor or weightroom mat.

So what does the barefoot portion of a workout actually look like? For us, it begins with cold stretching, including plantar fascia rolls, foam rolling, and standard static pre-workout stretches. We'll then put the athletes through a series of simple dynamic movements and agility ladder drills such as skips in all directions, butt kickers, spidermans, toe kicks, inchworms, and shuffles in all directions.

Next come mobility drills, such as lunges in various planes, hurdle walks/duck-unders, single-leg reaches in multiple planes, and various balance activities such as one-quarter jump-and-lands on one or two legs, hops, balancing on one leg with eyes closed, single-leg chopping patterns with core balls, and light bounding.

We also use our barefoot training time as an opportunity to develop the core with a number of upright standing exercises, such as partner anti-rotation, cable chops, and resisted lumbar cable extensions. By placing the athletes in positions that imitate live basketball action but without the usual support of their shoes, we enhance the sport-specific foot and ankle sensory system. And by improving the foot's tactile feedback and gripping strength, we provide benefits not only for the foot and ankle complex but all the way up the kinetic chain to the knee, hip, and lumbar spine.

At the end of a barefoot session, stretching and recovery includes strap stretches and foam rolling. We also use light jogging in the cooldown portion of some workouts, along with locomotion patterns such as walking with toes and feet pointed in, out, and up, walking on toes, shuffling in circular patterns, and backward jogging and running.

In addition to our traditional cooldown modalities, we also employ yoga during some sessions, particularly in the summer and the early preseason. This allows additional opportunities to stretch and maintain tissue quality while providing a refreshingly different type of ground-foot interaction.

The most striking thing about yoga work with our players is the extent to which they struggle to maintain the balance necessary for even basic poses such as the warrior series, high lunges, extended triangles, and downward facing dog. But improving balance is part of the reason we use barefoot training in the first place, so as they make progress in yoga, we know they are adding a new dimension of awareness and proficient mobility that will transfer to the entire kinetic chain.

As our athletes grow more comfortable with barefoot training, we gradually get them out of their shoes more and more often. For example, after regular conditioning sessions, weightroom workouts, and sled work, we might have them perform cooldown and stretching in bare feet on our indoor turf to keep the foot muscles engaged and maintain the strength gains they've made.

One question we have considered at length is how much barefoot training athletes should perform. We believe that once they've been evaluated and introduced to barefoot work, they should do as many training activities unshod as is practical. In our conditioning program, the barefoot portion of a workout typically takes between five and 20 minutes--so while it's certainly not the bulk of training, it is a significant part of the broader program.

I've seen demonstrably positive results from incorporating this type of training into athletes' workouts on a regular basis. Since we first implemented barefoot work in the summer of 2007, we have noticed a significant drop in episodes of anterior knee pain, ankle sprains, and low back pain among our basketball players. In fact, during the 2008-09 men's season, no one missed a game due to an ankle sprain or any form of lower extremity pain. I'm confident that our barefoot protocols contributed to this success.

Is barefoot training the secret to solving all foot, ankle, and gross movement problems? Certainly not. But with the outcomes we've witnessed, we won't be dropping it from our training program any time soon. After all, why would humans have such an incredibly complex mechanism as the foot if it wasn't intended to move freely?

Sidebar: STAYING SAFE
While barefoot training is a safe way to enhance foot strength and functionality, like every training activity it carries some risk. Here are a few pointers on how to minimize the chance of injury:

• Before every barefoot training session, inspect the surface for sharp objects, such as broken glass, pieces of metal, or anything else that could cause cuts or puncture wounds.

• Athletes with a wound on their foot should not train barefoot, especially if they cannot keep the wound covered with a secure bandage. Diabetic athletes should be especially cautious, as they have an increased tendency to develop foot ulcers.

• In most cases, athletes should not go barefoot in the weightroom--the risk of dropping a plate, dumbbell, or other piece of equipment on an exposed foot is too great. There are just two exceptions in our facility: during prep work when no one in the weightroom is handling free weights, and while I evaluate squatting technique, because it is beneficial to see the unshod foot as it moves during squats.

• As mentioned in this article, athletes with high arches and those with pre-existing foot or ankle conditions usually should not go barefoot, as they may need cushioning and/or orthotic support at all times to avoid injury. When in doubt, consult a podiatrist.

• As with any new form of training, the body requires an adaptation period. When introducing barefoot training, start with just a few minutes of light stretching and movement prep at each workout, and gradually add greater challenges as the athletes grow more comfortable.