‘Four legs good, two legs bad’ claimed the pigs in George Orwell’s ‘Animal Farm’ in a simplistic summary of their beliefs. While not as extreme as Orwell’s pigs, over the last ten years or so, a percentage of the running community, particularly the barefoot running crowd, adopted a similar motto: ‘Heel strike bad, forefoot good’. But just as the pigs had to write another commandment to cover the fact that birds have two legs but are still good, so are runners having a rethink. As Socrates is quoted as saying, ‘the beginning of wisdom is the definition of terms’, so let us clarify what we are talking about. In running terms, to heel strike is to land heel first and roll through the foot, taking off from the toes, much the same as when walking. A forefoot strike is when the front of the foot hits the ground first and the heel sinks onto the ground afterwards. In some instances, such as when running quickly, the heel stays off the ground completely. To throw a spanner in the works, people also talk of a midfoot strike, which refers to landing on a flat foot and is a kind of ‘forefoot-lite’. The basic premise of the ‘forefoot good’ argument is that faster runners tend to land on the forefoot. A study of habitually barefoot runners in Kenya showed that they tended to land forefoot first, giving fuel to the argument that not only do good runners run in bare feet, they land on the forefoot as well. One for us comrades! Until another study, also of Kenyan runners, found that over half of their subjects landed with a heel strike. It’s not unusual for two papers to contradict each other, and for people to side with the authors of whichever paper suits their own beliefs, which is what happened. The barefoot forefooters on one side, the naysayers opposite. Sadly, as is often the case, both sides ignored context, and that context is still ignored whenever the question is raised. The original study was conducted in the highlands, where the ground tends to be harder and landing on a softer foot is advantageous. The second study was performed in a region where the ground tends to be sandy and softer under foot, meaning the runners had to land on a slightly stiffer leg to compensate. Slope – whether uphill or down – is relevant as well. A study of elite mountain athlete Kilian Jornet’s foot strike over the course of a race shows a tendency to use fore-mid foot on inclines and a slight increase in rear foot striking in the later stages of an event, possibly due to fatigue. Several studies have shown that landing on the forefoot reduces forces around the knee, seemingly a huge bonus and one that is touted as the Holy Grail by forefoot advocates. However, that load shifts to the calf and Achilles tendon instead. Which is better? That depends on a multitude of factors, once again meaning there is no right or wrong answer. Someone with a sore knee might benefit, as long as they don’t also have very tight calf muscles or an Achilles problem. Given that calf muscles tend to tighten somewhat with age, actively trying to run on the forefoot as you get older may well cause more harm than good. Another contextual factor that needs to be considered is speed. Faster runners tend to land on their forefoot, but that is more a product of their speed than the cause of it. To add confusion here, a group in the UK looked at the foot-strike patterns of runners towards the end of the World Championships marathon, and found that over 60 percent were heel striking, so not all fast runners land on their forefoot. Additionally, for a slower runner, using a heel strike pattern is actually more energy efficient, suggesting that for longer distance events many folks would be better off heel striking. Now that we have our definitions and a summary of the arguments, let’s divide happily along our black versus white, forefoot- versus heel-strike lines. But as you can see, that’s no easy task, and there’s an awful lot of grey between black and white.
Andrew O’Brien is a chartered physiotherapist and the owner of Wannarun Physiotherapy and Running Clinic at Westport Leisure Park. He can be contacted on 083 1593200 or at www.wannarun.ie.
This post first appeared in the Mayo News
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