Running Form

6

Improving Foot-Strike Pattern

It takes just a few seconds during form drills to transform from a heel-striker to a midfoot-striker. However, the total transformation—to the point at which all running is completed with a midfoot-striking pattern—can take several months.

The reason for the extensive transformation period is not that it takes a long time to learn how to hit the ground midfooted. As mentioned, most heel-striking runners can develop a midfoot-strike pattern nearly instantly, when instructed to do so. However, heel-striking runners won’t necessarily preserve the midfoot-strikes when they move from drills to actual training. In fact, they will usually fall back into their familiar heel-striking pattern. Most runners’ neuromuscular systems are not eager to make sudden changes in form, even when they have the capacity to do so.

In this case, the stubbornness of the neuromuscular system is a good thing. Why shouldn’t the heel-striking runner become a midfoot-striking zealot and instantly be saved from heel-strike peril? The basic problem is that shifting from heel-striking to midfoot-striking is wonderful in the long term (as it improves performance, enhances economy, and reduces the risk of injury); but it can produce physical problems in the short term if the shift is too abrupt.

As a runner moves along in heel-striking mode, each collision with the ground causes impact forces to pass directly through the heel, up the leg, and through the knee at a very high rate. The knee and hip areas in particular must carry out a lofty level of work to withstand, control, and react to these rapidly applied forces. In addition, the shin muscles are highly stressed, because they control the “slap-down” of the foot on the ground (ankle plantar-flexion) which occurs immediately after a heel-strike and which places great strain on the shin muscles and tendons. Only moderate pressure is placed on the calf muscles and Achilles tendon during heel-striking.

With midfoot-strikes, the force patterns change dramatically. Each impact with the ground immediately distributes forces throughout the foot and ankle. Because the runner is landing on the middle of the foot, there is no slap-down action (plantar flexion) of the ankle and foot. Instead, the ankle begins to undergo dorsiflexion immediately after impact, with the top of the foot moving closer to the shin instead of away from it. This places extra strain on the Achilles tendon and calf muscle complex (gastrocnemius and soleus), which must work together to prevent excessive dorsiflexion approximately 90 times per minute per ankle (assuming a decent cadence of 180 steps per minute).

It is not bad to ask the Achilles tendon and calf muscles to engage in more work per step with midfoot-striking. But if you have been a heel-striker, this will be new, and the introduction of new forces when running can result in problems with the muscles and connective tissues, especially when those forces are repeated 5,400 times per leg over the course of a one-hour run. This explains why traditional heel-strikers who don a pair of minimal shoes (or become sudden converts to barefoot running) and then go out for a 60-minute run often wake up the following morning with their calves as taut as suspension-bridge steel cables, sending a very doleful message of pain to the brain. Each calf was simply not ready to be insulted more than 5,000 times after basically sleeping through months and even years of heel-striking workouts. The mechanism for malady here is that a change from traditional, high-heeled running shoes to minimal shoes with little heel elevation usually changes form, pushing the runner naturally toward midfoot-striking.

The Perils of Too Much, Too Soon

This pitfall during the change from heel- to midfoot-striking partially explains what happened several years ago when, following the publication of a book that championed unshod-running, Born to Run, countless runners hit the streets and trails with absolutely nothing on their feet (1). The result was an epidemic of Achilles tendonitis, calf pain, calf-complex tightness, and even inflammation and stress reactions in the metatarsal bones of the feet which forced many runners to conclude that barefoot running was not even close to the magical activity described in the top-selling book (figure 6.1).

The difficulty, of course, was not with barefoot running per se (or even with the increased reliance on midfoot-striking), but rather with the too-rapid transition from shod to unshod running (and thus from heel- to midfoot-striking). Changes in form and alterations in training always require a slow and careful approach if a runner has any interest in minimizing the risk of injury. A more careful transition involves a very gradual immersion into the world of midfoot-striking, rather than the abrupt insertion of a challenging 60-minute run (with all impacts on the middle of the feet) into the training program.

Figure 6.1 While shifting to unshod running does improve form and enhance running economy, if carried out too abruptly it can also lead to temporary problems in the calf, Achilles tendon, and even the metatarsal bones of the foot.

One of the criticisms of the midfoot-landing strategy is that it simply changes the “hot points” in the leg (where impact forces are felt to the greatest extent and more work is carried out per step) and shifts the locus of potential injury from common heel-strike injury areas such as the heel, shin, knee, and hip to possible midfoot-strike injury areas such as the Achilles tendon, calf, and metatarsals of the foot. Studies in which participants quickly shift from heel-striking to midfoot-striking tend to support this contention. It is true that if you put a group of heel-striking runners on a program of midfoot- striking and enforce those midfoot-landings to the exclusion of the usual heel-strikes, most of the runners will be injured in a relatively short period of time. Further, most of those injuries will occur in the back of the lower part of the leg and also in the metatarsal bones of the feet, which are replacing the heels as “initial impact acceptors” during the first moments of stance. However, the conclusion that midfoot-striking is linked with a high rate of injury is not correct.

If an individual who has never performed biceps curls suddenly completes 100 reps of biceps curling with significantly heavy dumbbells and suffers from agonizingly painful biceps muscles the following day, should we conclude that bicep curls automatically produce injuries? No, it would be more realistic to conclude that the amount of curling—not the curling itself—led to the pain. Whether an injury will occur is determined by the amount of training, the underlying strength of the muscles and connective tissues involved in the activity, and the magnitude and loading rate of impact forces.

And that is why heel-striking is in such trouble when it comes to the injury argument. With heel-striking, the rate of loading of impact force within the leg is significantly higher, compared with midfoot-striking (refer to figure 2.3). This means that the muscles and connective tissues have less time to react to the forces to which they are exposed with each collision with the ground. The time to initial peak impact force is much shorter with heel-striking, compared with midfoot-strikes.

If this concept is confusing, think of it this way: Would you rather be struck with a hammer suddenly on the bottom of your tibia (your main shin bone) with a force equal to three times your body weight, or would you prefer to have that kind of force gradually applied to your tibia? The hammer blow is like heel-striking, and the gradual application of force is like midfoot-striking (remember that impact force travels up the leg much more rapidly with heel-striking).

Another key point to bear in mind is that the heel-striking runner usually hits the ground with a relatively straight leg, with the landing foot well in front of the body. By contrast, the midfoot-striker hits the ground with the foot closer to the body and the body’s center of mass, and with the knee in a softer, more-flexed position compared to heel-strikers.

Which mode provides a softer landing, with less impact force travelling up the leg at high speed? Heel-striking is like ramming a hard pole into the ground at high speed, while midfoot-striking is like landing on a responsive spring (with ankle dorsi-flexion and knee flexion providing the springiness).

If you still believe that midfoot-striking is associated with a similar or even greater injury rate, compared with heel-striking, consider this scenario: Imagine you are standing on a high curb, about 24 inches high, above a cement roadway. You are going to jump down onto the road, and you must land on one foot (as you do when running). Would you rather make your landing on your heel with a straight, hard leg, or would you prefer to land midfooted with your knee flexed and your ankle ready to dorsi-flex to absorb the impact shock? Which plan carries the greater risk of injury? Do you still want to be a heel-striker when you run?

Drills for Transitioning to Midfoot-Striking

What follows here are drills that will help you make the transition from heel- to midfoot-striking. Please note that the initial drills should be carried out barefooted in order to provide superior proprioception and therefore a better feeling for midfoot-striking. This will help you sustain midfoot-strikes during your training and races, when you are wearing shoes. All drill durations are measured in minutes, and all should be performed with soft, flexed knees.

`PHASE ONE: BAREFOOT`
`Activity`	`Duration (minutes)`
`Walk in place with midfoot-landings`	`1:00`
`Jog in place with midfoot-landings`	`4` × `1:00, with a short break in between each minute`

Both the walking and jogging in place must be completed with a cadence of 180 steps per minute (190 if you are an elite athlete); use a runner’s metronome or metronome app on your smart phone to verify. Conduct these drills before the main portion of your overall workout. Complete the drills about five times over the course of one week, or until you are completely certain that you can carry out both activities with midfoot-landings. You are then ready to move on to Phase Two.

Very important: As you are jogging in place, make sure that you make initial contact with the ground in the middle portion of the foot, with the heel striking the ground very shortly after this midfoot-strike (yes, the heel hits the ground on each step, but only after the midfoot region has “touched down.”)

`PHASE TWO: IN RUNNING SHOES`
`Activity`	`Duration (minutes)`
`Walk in place with midfoot-landings`	`1:00`
`Jog in place with midfoot-landings`	`4` × `1:00, with a short break in between each minute`

Both activities must be completed with a cadence of 180 steps per minute (190 steps per minute if you are an elite athlete); use a runner’s metronome or metronome app on your smart phone to verify. Complete the drills about five times over the course of one week, or until you are completely certain that you can carry out both activities with midfoot-landings while shod. You are then ready to move on to Phase Three.

`PHASE THREE: BAREFOOT`
`Activity`	`Duration (minutes)`
`Jog in place with midfoot-landings`	`1:00`
`Jog forward with midfoot-landings while taking “baby steps”`	`4` × `1:00, with a short break in between each minute`

Both activities must be completed with a cadence of 180 steps per minute (190 steps per minute if you are an elite athlete); use a runner’s metronome or metronome app on your smart phone to verify. Complete the drills about five times over the course of one week, or until you are completely certain that you can carry out both activities with midfoot landings while barefoot. You are then ready to move on to Phase Four.

Very important: As you are jogging forward with baby steps, make sure that you make initial contact with the ground in the middle portion of the foot, with the heel striking the ground very shortly after this midfoot strike (the heel hits the ground on each step, but only after the midfoot region has “touched down.”)

`PHASE FOUR: IN RUNNING SHOES`
`Activity`	`Duration (minutes)`
`Jog in place with midfoot- landings`	`1:00`
`Jog forward with midfoot-landings while taking “baby steps”`	`4` × `1:00, with short break in between each minute`

Both activities should be completed with a cadence of 180 steps per minute (190 steps per minute if you are an elite athlete); use a runner’s metronome or metronome app on your smart phone to verify. Complete the drills about five times over the course of one week, or until you are completely certain that you can carry out both activities with midfoot-landings while shod in your regular training or racing shoes (verify with video analysis, if possible). You are then ready to move on to the slightly more complicated drills in Phase Five.

Very important: As you are jogging forward with baby steps in shoes, make sure that you make initial contact with the ground in the middle portion of the foot, with the heel striking the ground very shortly after this midfoot-strike (the heel hits the ground on each step, but only after the midfoot region has “touched down.”)

`PHASE FIVE: IN RUNNING SHOES`
`Drill`	`Distance`	`Duration`	`Repetition`
`1`	`200 meters`	`120 seconds`	`1 time`
`2`	`200 meters`	`90 seconds`	`1 time`
`3`	`200 meters`	`60 seconds`	`1 time`
`4`	`200 meters`	`45 seconds`	`2 times`
`5`	`200 meters`	`30 seconds`	`2 times`
`Note: All drills use a midfoot-strike pattern. Cadence should be 180 steps per minute for non-elite runners (190 if elite); verify cadence with a metronome. Verify midfoot-striking with a video-analysis app, if possible.` `Courtesy of Walt Reynolds, NovaSport Athlete Development.`

Note for Phase Five: If for any phase you cannot sustain midfoot-striking at the specific, recommended pace, do not continue to the next drill. For example, if during Phase Four from above you find that you are reverting to heel-striking or are not able to maintain the pace, do not attempt to continue on to the final Phase Five. Instead, continue working on Phase Four, perhaps on a subsequent training day, until midfoot-striking can be maintained at the required cadence and running pace.

A common observation is that once runners have mastered midfoot-striking in drills, they often revert to heel-striking when they compete or carry out fast running in training. The work in Phase Five teaches a runner to utilize midfoot- striking, even at high velocities.

Please note: The form drills are put together in a way that makes them part of a very effective warm-up before a training session or competition. If the drills are conducted before a workout, proceed directly from the drills right into the training session; within the workout, gradually introduce more and more midfoot-striking over an extended period of time (the gradual inclusion of midfoot-striking lowers the risk of injury to your foot, Achilles tendon, and calf). For example, during the first week of drills you may want to focus on running with midfoot-strikes for about 10 percent of your normal training period (whatever you do after the drills are completed); the rest of the time, simply run with your customary form. During the second week of drills, transition to running with deliberate midfoot-striking for around 20 percent of your training time, and so on.

Contrast Runs

A couple of times per week, after an adequate warm-up, supplement the drills in this chapter with contrast runs, as follows:

Run at a moderate speed and a cadence of 180 steps per minute for approximately 50 meters with straight, hard legs, with little knee flexion at ground contact.
Rest for a few moments, and then run 50 meters at a moderate speed with a cadence of 180 steps per minute, with soft, slightly flexed knees at ground contact.
Rest for a few moments, and then run at moderate speed for 50 meters with straight, hard legs and a cadence of 180 steps per minute, landing on a heel with each step.
Rest briefly, and then run for 50 meters at a moderate speed with a cadence of 180 steps per minute and with soft, slightly flexed knees at ground contact, making sure that each landing occurs on the midfoot region.
Repeat Steps 1 through 4 one more time.

At first, make sure that the contrast running is carried out on a soft, forgiving surface such as grass, beach sand, a gym floor, or a rubberized track. During each 50-meter segment, be aware of how different each running style feels and how the midfoot-striking leads to springier, more comfortable running with less perceived effort and discomfort. Contrast running helps to reinforce the form essentials of midfoot-landings, “springy” legs, and good cadence.

Summary

Compared with heel-striking, midfoot-striking reduces the rate at which impact forces travel up the leg and therefore decreases the risk of injury. However, a shift from heel- to midfoot- striking can actually increase the chance of injury, if it is not carried out in a careful and gradual manner. Five phases of drills, plus contrast running, can gradually transform a runner’s ground-contact pattern from heel- to midfoot-striking over time. When the drills are performed with a gradual change in training (so that a runner is spending progressively less training time in heel-striking mode), eventually “drilling” and running will merge, and a runner will become a full-fledged midfoot-striker with faster running performances and less risk of injury.

References

C. McDougall, Born to Run (Knopf, New York: Vintage, 2009).