By Dr. Christopher Moran
Running, Not Walking: Human running is not the same as walking, only performed faster. This ‘technique’ of heel-to-toe running was invented by the same people who invented uber-padded running shoes to solve a problem that the shoes themselves created, namely, the problem of contacting the heel bone (calcaneus) on each stride. Some of the potential injuries to the runner because of landing on the heel with the leading leg way out in front of the body and the resulting mechanical disadvantage to maintaining running speed have been covered previously (see Part 2 in this series).
In contrast to landing on the heel bone while the leading leg is out in front of the body, softly coming down on the mid to fore foot while the landing foot is more or less directly under the hips makes for a much smoother and softer touch down on the foot. Some of the advantages of this contact of the foot with the ground include stability of the foot and ankle. As the mid-foot contacts the ground surface first, the toes are pointed slightly downward, the ankle is in a neutral position and the knee is slightly bent ready to absorb the shock of the body weight landing on one leg. If the foot encounters any stones or uneven terrain, the foot in this neutral position can quickly adapt, sparing a turned ankle. Contrast this with running at speed and landing on an outstretched leg in front of the body, knee relatively straight and striking the heel first. With the toes skyward, the heel making contact with the ground first with its small surface area is much more likely to roll the ankle if landing in a small hole. An extreme example of this idea is running in high heels and landing on the very small surface area of the heel. Even very small defects in a smooth running surface would easily produce a sprained ankle, knee or worse, if the landing isn’t perfectly each and every time.
Moving Forward: Forward momentum and therefore running speed is not checked by the stopping action of the heel-first strike in front of the body, which takes advantage of normal and moderate muscle contraction instead of sudden forceful contractions to regain speed lost through breaking.
Free Energy: In conjunction with a faster turnover rate (covered in the next section), landing on the mid or fore foot quickly stretches the elastic tendons and ligaments and compresses the arches of the feet, storing this energy to be released back in the form of a natural ‘spring’ which helps propel the body forward without relying solely on muscle contraction alone. It won’t work, however, if turnover rate isn’t optimum (too slow of a stride rate) since a tendon stretched for too long a period of time dissipates this energy instead of releasing it to spring the body forward (more on this next).
Make It Snappy: Increasing the rate of turn-over, the number of times each foot contacts the ground per minute, while landing with the foot under the hips also serves to decrease any breaking motion due to over striding. Evaluation of elite medium and long distance runners has determined that the average turnover rate among these world class runners is 180 steps per minute, regardless of the leg length of the runner or even the speed of the runner at the time of evaluating turn-over rate (investing in a $30 metronome the size of a business card at a local music shop or even a free app on your phone is a great tool for training up to this turnover rate). With this stride, the quadriceps are not fatigued by contracting when the heel hits the ground in front of the body, the hamstrings don’t need to pull the runner’s body along as the foot maintains contact with the ground for too long a period of time and the calf muscles (gastrocnemius and soleus) don’t have to contract forcefully in order to propel the body upward and forward to make up for the breaking motion that had slowed the body’s speed initially. This shorter time of ground contact with the foot allows for the tendons in the feet to be stretched, storing up energy, then releasing this energy in the form of an added push off when the tendons naturally snap back to normal length. This ‘free energy’ is efficient and helps to increase the power of the stride passively without requiring fatiguing muscle contraction, much like the tendons of a kangaroo work. With longer, slower strides, this extra potential energy within the foot and ankle tendons is dissipated as the tendons remain stretched for too long a period and do not snap back. Putting in a training session running barefoot in a soft, cushy lawn will help to remind the body of its natural, efficient stride. Hill work is another way to get the feel of this proper running technique.
Use the BIG Muscles: Pulled hamstrings, strained quads, strained Achilles tendon, shin splints and tendinitis…all injuries linked to the overuse of the smaller and relatively weaker muscle groups when running. The largest and strongest muscles in the body are the ones that should be doing the ‘heavy lifting’ so-to-speak. Following the touching down of the foot under the hips, how about using the gluteus maximus to pull the leg through and propel the body forward? These muscles are naturally strong and have endurance fibers that can literally go all day long. Same is true with the swinging of the leg forward in the stride. Using the super-strong hip flexors lying in front of the hip is more efficient than using the quadriceps, which are more susceptible to fatigue. Get the feel of pulling the leg backward using the glutes (tighten up the butt muscles) and swinging the leg forward using muscles at the front of the ‘hip’ will allow the other supportive muscles to contract less forcefully and less frequently, resting them during more of the stride so they won’t be the limiting factor in your long endurance run or speed.
Next in the series, we will look at ways to effectively treat some of the common running injuries.
Dr. Chris Moran is in private practice at Traverse City Knee and Shoulder Solutions in Traverse City, Michigan and may be reached by calling (231) 943-2100 or by e-mail at firstname.lastname@example.org.