Since Sock Doc began, one of the most common questions I have been asked is, “Sock Doc, I’m running in minimalist shoes (or barefoot), but I’m still injured—why?” This question tells me one thing: Runners think that if you get out of your oversupportive, cushioned running shoes and orthotics, injuries magically disappear. Unfortunately, this is not always the case because running in minimalist-type shoes and/or barefoot will not necessarily keep you injury-free. Proper footwear (or going barefoot) is only part of the injury-free prescription.
Running in minimalist shoes and being barefoot clearly helps the entire body. Improvements in nervous system function, muscular function, and balance, proprioception, and overall health can be seen in those who keep their feet close to the ground and out of motion-altering footwear. But often, injuries are not just because what you’ve got on your feet isn’t right for you. For most athletes, the rest of the regimen is more important: diet, training, and overall stress. All these factors determine whether you will get injured (or come down with an illness) or not. Many athletes also forget that training itself is a two-part equation: working out plus rest.
Diet is perhaps the most important factor. What you eat and drink plays a major role in how your body is able to function during the day at work, at home, and while training. It also has a lot to do with how well you rest (sleep). For example, a diet high in omega-6 vegetable oils, such as corn, safflower, and soy oils and partially hydrogenated fats, will creep up your inflammation levels, resulting in muscles working harder than they would otherwise to function normally and recover.
Significant stress is placed on the cardiovascular system too with diets high in inflammatory fats and, obviously, every runner wants an optimal cardio system. A high-carbohydrate diet, especially refined sugars like high fructose corn syrup, white sugar and flour, and even agave, will contribute to the inflammation and even increase insulin levels over time. Eventually, your tissues become resistant to the insulin, and blood glucose handling problems will result. You may bonk or underperform in a race because of this, or have mood swings and general body aches due to carbohydrate sensitivity. Overall, your diet influences your entire body, including your joints, tendons, ligaments, and especially how your muscles function. Your body ultimately becomes out of balance; you get torqued or twisted a little, so to speak, as postural changes affect your gait, balance, and function.
Nervous system function is closely related to the diet, and what follows are muscular imbalances because of the nervous system’s response to the diet. Your calf may work harder than it used to on one leg because of the gait imbalance, or your hamstring may work more because your quad isn’t functioning correctly due to the gait and joint disturbances caused by the dietary imbalances. These nutritional dysfunctions affect your nervous system, which, in turn, affects the muscles. In fact, addressing dietary imbalances is how I have been able to successfully treat patients when others only look at the injury itself, not where it came from.
Nutrients have a role here too, but they are typically much more individualized than overall dietary recommendations. Nutrient deficiencies and imbalances will have specific reflections on physical structure. A good example is a muscle cramp. Although a cramp can be due to a local muscle or tendon problem, it is often from a dietary problem (dehydration) or a nutrient imbalance or deficiency (sodium, potassium, magnesium, or calcium), resulting in a physical symptom. Cramping alters muscle function, not just in the muscle experiencing the cramp, but in other, synergistic muscles and those affected by gait. Eventually, this can lead to an injury to a muscle, tendon, ligament, or bone, and perhaps a direct injury from the cramp itself.
Training and racing also play a major role in injuries, perhaps as much as diet. If you’re training too anaerobically, you’re likely to get injured. Racing too much will have a similar outcome. The reason athletes get injured when they overtrain is partly due to the imbalance caused between training and recovery, and in part due to nutritional considerations. High-intensity and long-duration workouts require a certain amount of recovery, and it is different for everybody to some extent. Without enough rest, your body won’t recover for the next workout. Muscles, tendons, and ligaments are affected directly by the workouts, but they are also affected by hormonal changes and nutritional considerations. For example, it is well known that high-intensity workouts and even aerobic workouts lasting over a few hours will increase an athlete’s stress hormone, cortisol. This increased cortisol level will affect blood sugar levels, and that will affect various muscular functions as well as gait.
Consider the endurance athlete (perhaps yourself) following a long race, such as an Ironman or a marathon. Even if you’re 100% pain-free, most likely your posture changed afterward—a hip may be higher on one side or a shoulder rotated on the other side. These imbalances weren’t there before the race.
A lot of these imbalances have to do with hormonal and nutritional changes in your body, resulting in physical imbalances. Additionally, hormones such as cortisol have to be broken down by the liver, and that requires nutrients such as antioxidants, vitamins, minerals, and sulfur amino acids like L-cysteine. Sulfur is a major component of cartilage. Think about what may happen to your joints if you’re training too hard and your body is constantly making a lot of cortisol. Your joints will suffer. And high cortisol levels are a major reason for insomnia and waking up in the middle of the night. This impaired rest will further impact athletic performance and health, as the recovery will not be available to offset the desired training.
So you can see the various ways nutrition and training (working out plus rest) can impact the body in more than one way, and often result in an injury if imbalances occur.
Stress isn’t just about working out too much either. If you’re stressed out at work, stuck in front of a computer, have a long work commute, and have family stresses on top of that, your body will perceive it as if you’re training hard all day long. Cortisol levels will elevate, beneficial sex hormones like testosterone and progesterone will plummet, and muscular imbalances will occur, just as they do with overtraining and dietary and nutritional imbalances. The end result is often the same in all three cases—an injury shows up, despite what you’re wearing for footwear.
Yes, proper footwear is important, but if I could only choose one thing to change in an athlete, it would be either his or her diet or training, depending on their individual circumstance. I’ve always been able to help injured athletes, even before I knew the effect of minimalist shoes and going barefoot; it was just more difficult to ascertain. It’s easier now because of my knowledge and hands-on experience (personally and with patients) that footwear is an important factor. I like to tell patients, “Look at your overall stress and fix what you can fix.” This means you can often fix your diet, your training, and your footwear more easily than perhaps your job or your family situation. So eating healthy, training properly, modifying your lifestyle, and strengthening your entire body by wearing minimalist or no shoes all have their respective impact, but on an individualized basis. If you don’t pay attention to each one and keep them in balance, or let one factor falter, then your body will let you know with pain.
