How Poor Form Leads To Marathon Cramping
As we learned in the previous two articles on muscle activation and treating the cause of running injuries, your body will always compensate when one muscle group isn’t working correctly by rerouting the work that needs to be done to another muscle group.
Meaning, if your glute muscle is inhibited and not firing correctly, your leg won’t simply stop working. Instead, your brain tells your muscles, “hey, this glute isn’t getting the job done, let’s fire the calves more forcefully to make up for the lack of power.” This “rerouting” occurs unconsciously and often you’ll never even realize it occurs.
Let’s look at two very specific and common examples of form breakdowns that occur late in a marathon and how they potentially impact cramping.
Slouching And Poor Posture
One of the most common issues is slouching, or leaning at the waist, as you get tired. Keeping your shoulders and chest back and your spine in a neutral position for two, three, or even four hours is a difficult task for your core (hips, abdominals, lower back and glutes). Most runners lack the strength to hold themselves in the optimal posture for three to four hours.
As a result of their weakness, they slouch (or lean forward at the waist), which will tend to sit the butt backward to counter balance their upper body’s forward position. This results in over-striding (landing with your foot out in front of your center of mass), which dramatically increases the impact forces that travel up the leg as the foot lands.
Over striding also puts the hamstrings in a vulnerable position at ground contact and forces them to do more work to pull the leg through since the glutes can’t be activated as efficiently. If you suffer from frequent hamstring cramps during the marathon, I contend this is the likely cause.
RELATED: What’s Your Stride Rate?
Lack Of Hip Extension
I believe one of the main culprits of marathon cramping, especially in the calves, is a product of reduced hip extension, which is much more difficult to recognize than slouching.
Hip extension is the act of driving your entire upper thigh (and leg for that matter) backwards after your foot contacts the ground. The power for this movement is generated primarily from the hip and glutes and it is perhaps the single most important factor in your ability to run faster. The more powerful your hip extension, the faster you will go.
As you get further into a race, the forceful contractions required from the hip and glute muscles to sustain a fast pace become more difficult to generate (this is especially true if you went out too fast and fatigued your intermediate muscle fibers early). To compensate for the hip and glute getting tired, the body recruits the calf and quad to help generate the power needed to maintain marathon pace. Since the calf and quad aren’t accustomed to such a large workload, they quickly fatigue and begin to cramp.