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Heel counters: what’s all the fuss about? By Dr. Chris Bishop PhD Shoe design is a difficult task. With the common goal to reduce mass of a shoe, how can designers include all of the technology they desire without the shoe feeling like a brick? The argument is often that shoes have been over engineered, and it is often questioned what technical design features can be removed without compromising the function, structure and support that a technical running shoe provides. One of the main design features in the spot light is the heel counter. Do we need it…at least in its rigid form? If yes, is it internal or external? Walk into most shoe shops and you will get the standard line that a firm heel counter will support the foot during gait. But really, is this true? Do we know this? What is its role? Does it control foot pronation? Does it aid in stability as the foot is loaded? Does it simple provide structure and shape to the shoe? Despite the often quoted conceptions about what a heel counter actually does, the reality is that little is known from a scientific point of view. Firstly lets look at its intended role and then we can explore the supporting science. The shape (construction) of a heel counter can have a significant impact the overall fit and feel of the shoe. We know that heel fit is a really important consideration in the overall comfort of a shoe. Surprisingly, differences in the shape, degree of padding, depth, how well the shape of the heel matches the shape of the back of the heel counter can be overlooked, particularly in a retail environment. It is then sometimes overcome by different lacing techniques, when really the 'openess' or design of the heel counter doesn't match the individuals heel shape. This can cause significant issues with internal heel wear or rubbing on the posterior aspect of the calcaneus (especially if a haglunds deformity is present). The suggestion that an external heel counter is 'better' because it allow for
the natural movement of the foot during midsole compression and reduce wear is also largely unsubstantiated and simply a belief. However the greatest misconception is that it somehow ‘guides’ the heel as the foot touches the ground and helps 'control' the heel from excessively pronating. When we delve through the literature and look at the science underpinning rearfoot shoe design, apart from the work of Nigg and Butler in the late 1980’s, minimal work has been done substantiating the presence of a heel counter in the modern athletic shoe. This doesn’t say that many of the shoe companies haven’t done their own R&D and simply haven’t published their work which I’m sure they have. But lets look at some of the findings out there with respect to motion control, fit and variability in response: In 2000, the late Alex Stacoff and co-authors compared hindfoot biomechanics during running both barefoot and in shoes. There findings contrast the previous findings in the literature that showed substantial and significant reduction of hindfoot eversion, identifying that the differences in calcaneal eversion between barefoot running and running with normal shoes were small and not systematic. Given these authors used more accurate methods by attaching markers directly to the bone rather than on the skin, it is likely that previous studies identifying a reduction in hindfoot eversion were measuring the movement of the shoe and/or skin, and not the true movement of the underlying bone. This indicates no motion-control benefits were identified. In 2007, Irene Davis and co-workers published their findings on the contribution of a heel counter to internal stresses of the heel pad during static standing. When comparing the results of a finite element model of the heel inside the shoe with and without a heel counter, the heel counter provided CONTINUED ON NEXT PAGE >>
