How Can Runners with Flat Feet Avoid Injuries?
There can be a wide range of diversity when it comes to foot posture. Typically, there are five foot shape categories: Highly supinated, supinated, neutral, pronated, and highly pronated.
Those classified as supinated represent a higher arch when standing still. Supinators also distribute their weight closer to the outside of their feet when walking. A neutral foot type will distribute an even weight while standing and walking. Their arch height is within normal range, and the amount of pronation they display during walking is within normal limits. Pronators, on the other hand, have an excessive range during pronation. In standing, their arch is often reduced, hence the term ‘flat foot’.
What are the benefits of pronating?
The term pronation is often labelled as a movement that should be avoided. But as it happens, pronation is a healthy movement of the ankle and foot that helps protect you from injury.
When walking or running, your foot will strike the ground at a high force. Studies have estimated that 1.7 times your body weight is accumulated in ground reaction force after each walking step. When transitioning to running, this ground reaction force can build up to three times your body weight. To reduce the risk of injury, your body needs to slow down the rate of loading and spread the distribution. Imagine slapping your flat, rigid hand on a concrete path versus hitting the ground with a loose, rolling hand. This is when pronating the ankle becomes extremely important.
When your foot makes contact with the ground, it begins to roll in. The bones of your ankle roll over one another, and your ligaments suddenly activate to prolong the reaction with the ground. This event also allows enough time for ground forces to be distributed to different areas of the lower leg and transition up the kinetic chain. So, despite what you may hear about the harmful effects of pronation, it is actually more helpful than dangerous.
Flat feet and running injury rates
Nielsen and colleagues conducted a study in 2014, which investigated if foot postures changed the rate of injury in runners wearing neutral shoes. The authors segregated 927 runners (1,854 feet) into five categories: highly supinated, supinated, neutral, pronated and highly pronated. Then, they assigned neutral shoes to each runner and observed their running, along with their injury occurrence over one year.
For first-time injuries, the rate of injury was 17.4% for neutral feet, 17.9% for supinated feet, 24.5% for highly supinated feet, 13.1% for pronated feet, and 33.3% for highly pronated feet. This particular paper concluded that “no significant differences in distance to first running-related injury was found between highly supinated, supinated, pronated and highly pronated feet when compared with neutral feet. In contrast, pronated feet sustained significantly fewer injuries per 1,000 km of running than neutral feet”.
This paper helps support the idea that pronation is a protective movement and is essential for reducing the risk of running-related injuries. However, it seems that pronation as a protective motion is not linear, and those with excessive pronation may not receive added benefits. Additionally, it does seem that fitting into the highly pronated category is quite rare. Out of the 927 runners analyzed in this study, only 18 runners were labelled as highly pronated.
Tips to run successfully with flat feet
1. Follow a realistic training regime
The vast majority of running-related injuries are caused by abrupt changes in training load. This involves increasing your overall mileage, changing your running terrain, and increasing your running speed too quickly, and may exceed your body’s capacity to tolerate external loads. So no matter what your foot shape is, it is important to train within your capabilities and progress slowly. This will allow enough time for your body to recover, adapt, and tolerate slightly harder efforts in the future.
2. Select comfortable footwear
A common misconception is to reduce the amount of pronation. With this myth in mind, runners who pronate are often provided with supportive shoes in order to correct this movement. Based on the information above, we know that pronation is a normal, healthy, and protective movement for runners. So, it is advisable to try several types of running shoes and choose the most comfortable pair. This would help match your preferred movement path, and you will thrive as a runner.
3. Strengthen your feet
If you have flat feet and are struggling with overuse injuries, it is important to build up your load tolerance. As the vast majority of running-related injuries are caused by abrupt changes in training load, you need to build up your running resilience by strengthening your feet. One of the best beginner exercises is walking bare feet or in minimalist footwear. This will boost the strength and function of the intrinsic muscles within the feet. Next, you can incorporate minimalist footwear into your training workouts like squats and lunges. Gradually increase the training load on your feet to strengthen them as much as possible. Continue to progress the demand of the feet to generate as much strength as possible.
There are many misconceptions surrounding the management of flat feet, the most common one being that pronation is not beneficial for you. However, there is no link between foot posture and injury. This is because foot posture is only one piece of a complex puzzle. If your training habits are sensible and if you wear comfortable running shoes, you are significantly reducing your risk of injury. Additionally, increasing your foot strength and function will help raise the foot’s capacity, contributing to running resiliency and the function of the entire kinetic chain.
1. Nielsen R, Buist I, Parner E, et al. Foot pronation is not associated with increased injury risk in novice runners wearing a neutral shoe: a 1-year prospective cohort study. Br J Sports Med 2014; 48: 440–7.
2. Dowling G, Murley G, Munteanu S, et al. Dynamic foot function as a risk factor for lower limb overuse injury: a systematic review. J Foot Ankle Res 2014; 7: 53.
3. Neal B, Griffiths I, Dowling G, et al. Foot posture as a risk factor for lower limb overuse injury: a systematic review and meta-analysis. J Foot Ankle Res 2014; 7: 55.