Closing the Gap: What a Massive New Study Reveals About Women's Running Shoes

Greg Marshall
11 minutes ago
4 min read

Women's running shoes and other race day gear

Female representation has received more attention in the last several years across many domains, but running footwear research is an area that’s still lagging. Research also shows that if women are leading academic research teams, they often eliminate the sex bias in study design that currently troubles the field. If there are more female researchers in running footwear science, they’re likely to help close the data gap.

In the present, at least we have the recent work of Tizian Scharl and his team in the Division of Biomechatronics at the Fraunhofer Institute for Manufacturing Engineering and Automation IPA in Bayreuth, Germany.

Their 2024 paper in Bioengineering is titled “Gender Differences in the Dynamics and Kinematics of Running and Their Dependence on Footwear.” The rest of can describe it as a one-hundred-and-seventeen page clinic on the form changes running shoes cause for female runners.

What they did

The study design included a few, notably cool things. Beyond a representative subject pool with eighteen males and nineteen females, they tested a large group of footwear types– eight in total, ranging from barefoot, to maximalist, to each runner’s own preferred shoe choice. They collected six samples in each footwear condition, providing a more comprehensive examination of how each runner moved in the shoe.

A photo of eight types of running footwear

The kicker for me is the speed protocol the team chose. They had each runner run in each shoe condition at two speeds. One of these was 10km/h (about 10 minutes per mile), and the other was self-selected as the speed they use for most of their training runs.

Why is this good? One of the biggest problems with this field of work is that researchers choose to match either the speed or the effort, and each one has trade-offs.

If you match speed, some subjects could find it as comfortable as a recovery run while other subjects are at more of a tempo run effort. Running form can change with effort, so it’s not quite an apples-to-apple comparison in that scenario.

On the other hand, matching effort so that the speed is different based on how fast a subject is used to running, sacrifices some ability to compare joint forces and total work, since those will differ depending on whether a runner is moving slower or faster.

By testing both protocols, Scharl’s team not only allows for comparison within their own study, but also helps build a bridge between other studies that have been hard to compare to one another.

What they found

There were a few key takeaways in their mountain of data. For one, they verified the findings of a handful of previous studies that examined just the differences between male and female gait features. That means something, because the footwear used over the decades has changed. Knowing that footwear alone has a big influence on certain gait patterns might throw into question whether or not previous gait differences between the sexes were real or just an artifact of the shoes used.

A figure showing difference in male and female joint angles in the different footwear conditions — The speed tested is stated in the title. The green, blue, and red boxes show what joint feature was measured. Larger measurements are shown to the left of the body if they were seen in women, and on the right of the body if observed in men. Within each box, the "BF" through "PS" represent the eight footwear types, with darker grey squares indicating a larger measurement than in lighter colored squares.

They also found that a lot of the differences between how men and women ran in the various shoes seemed to stem from the footstrike pattern. Women tend to forefoot strike more than men in more minimalist shoes, but they also heel strike more than men in high-cushion shoes. Most of those changes happen at or below the knee, with the differences in hip activity between men and women remaining predictable across the shoe types tested.

What it means

The team at Fraunhofer approached the study as if they were intent on remedying the decades-long data gap on female runners all by themselves, adding heaps of data to the conversation. Not only did they clarify some of the exact responses of females to different shoe types, but they also examined the male responses at the same time, giving us better grasping points for comparing how the female data may relate to prior male-centric footwear research.

Even with all of that, there’s ground left to be explored. They tested 8 shoe conditions; most were Puma shoes. There were a couple of minimalist footwear conditions, a couple of maximalist footwear conditions, a super shoe condition, and even a barefoot condition. The sacrifice they made in choosing the menu of shoes they did, is the ability to fully explore what differences exist across brands, but within a category. How do Puma max-cushion shoes compare to Nike max-cushion, for example?

Finally, this was a biomechanics study that looked at the forces and movement patterns at the joints of the body as the runners moved. There’s no clear way to tie it to things like the differences in energy cost that might also exist between the sexes, and the data is a long way from predicting injury risk.

The good news there is that we’ve more left to explore in order to make those connections. Right now, it’s a little clearer that “shrink it and pink it,” probably won’t hold up against another decade of footwear research and product development.