Is there a perfect foot strike pattern in running?

What is the foot strike pattern?

If you divide the foot into three geometrically equal parts, you will call these sections rear- mid- and forefoot. Now, imagine to have a device that can tell you which of these three parts was the first to touch the ground at each step. The output would be the foot strike pattern (FSP). Thus, you might be a rearfoot, a midfoot or a forefoot striker, depending on which part of the foot performs the touchdown first1. You could even go bigger and accurately locate the strike along the foot. Starting from the heel until the toe tip, you can give a number that locates the centre of pressure (point of force application due to the distribution of pressure under the foot) at contact2 (see Figure 1). It is very well known that the large majority (80 to 95%) of amateur runners run with a rearfoot strike pattern1,3.

Different foot strike patterns (shod and barefoot running)

Figure 1 Typical rearfoot (A) and forefoot (B) strike patterns during shod and barefoot running, respectively. The strike index values are presented as well. Taken from Santuz et al, Front. Physiol. 8, 958 (2017).

What happens when you change foot strike pattern?

First of all, changing FSP is not only a matter of modifying the ankle joint angle. The whole body weight distribution changes, being the landing point in a rearfoot strike pattern farther from the body’s centre of mass than it is in a mid- or forefoot strike pattern this small plateau is absent or visually unidentifiable (see Figure 2)3,4. This translates in a lower rate of force development in the mid- or forefoot strike pattern compared to the rearfoot1,3–5. The active peak vertical force (the main peak of the force-time curve, see Figure 2) is usually similar or lower in rearfoot compared to forefoot strikers3,4.

Ground reaction force and foot strike patterns

Figure 2 Typical vertical ground reaction force produced by two different foot strike patterns.

Moreover, when rearfoot strikers switch to a mid- or forefoot strike, usually the cadence (number of steps per minute) increases together with the flight time, while contact times decrease2–4.

Are all these differences good?

Unfortunately, the consensus on the topic is far from being reached. While some eminent scientists such as Irene Davis are strong advocates of forefoot striking (and barefoot/minimalist running)4, there are just as brilliant researchers (e.g. Jo Hamill)3 which take some distances from a final, definitive answer to the question “should runners change their foot strike pattern?”. Hamill recently published a study in which he reviews past research on FSPs trying to understand whether mid-/forefoot strike is more convenient from a running economy and injury prevention perspective3. If you reached this point of my article, I guess you will be disappointed to learn that Prof. Hamill concludes that there is no scientific proof whatsoever that can strongly support improvements in running economy or injury risk’s reduction of mid-/forefoot strike against rearfoot strike patterns. It always makes me laugh when Prof. Hamill, at the end of his talks, answers the fateful question with a laconic: “it depends on how you want to get injured!”.

Take home message

As I often like to conclude, trying new things is what keeps us motivated, curious, alive. Extremisms have a long failure tradition in human history. Defending one or the other foot strike pattern without understanding the implications of the choice, will not help the cause in favour of peaceful coexistence. So I guess that the best answer you can get when you ask an expert if you should change FSP, is that there is no answer. But that you should always be trying something new anyway.

References

  1. Santuz, A., Ekizos, A. & Arampatzis, A. A Pressure Plate-Based Method for the Automatic Assessment of Foot Strike Patterns During Running. Ann. Biomed. Eng. 44, 1646–1655 (2016).
  2. Santuz, A., Ekizos, A., Janshen, L., Baltzopoulos, V. & Arampatzis, A. The Influence of Footwear on the Modular Organization of Running. Front. Physiol. 8, 958 (2017).
  3. Hamill, J. & Gruber, A. H. Is changing footstrike pattern beneficial to runners? J. Sport Heal. Sci. 6, 146–153 (2017).
  4. Davis, I. S., Rice, H. M. & Wearing, S. C. Why forefoot striking in minimal shoes might positively change the course of running injuries. J. Sport Heal. Sci. 6, 154–161 (2017).
  5. Lieberman, D. E. et al. Foot strike patterns and collision forces in habitually barefoot versus shod runners. Nature 463, 531–5 (2010).