Is consumer behaviour towards footwear predisposing for lower extremity injuries in runners and walkers? A prospective study

gested that there is a subjectand task-specific locomotion pattern that is determined by many factors and that this preference for a particular motion path may explain why shoes have little effect on lower extremity kinematics. This new paradigm has given researchers ‘food for thought’ and has led to the new assessment tools such as how footwear may affect the determination of a runner’s deviation from the runner’s preferred path. A runner’s ‘preferred movement path’ may be interpreted in many different ways, one of which relates to the movement of the whole body system rather than a single joint movement. Joints and segments of the lower extremity interact to produce a smooth and efficient movement path. Thus, for an individual, there will be a movement path unique to them and, in Nigg’s words, would result in significant muscle adaptations if there are deviations from the ideal path. Such an analysis of the coordination of the body when running gives rise to analysis techniques based on Dynamical Systems Theory (Hamill, van Emmerik, Heiderscheit, & Li, 1999). It may be this systems approach could lead to a more fruitful evaluation of running footwear that what was used in the past. As an example, Taunton et al. (2002) identified the knee as the most prevalent site for running injuries. However, focusing on a single parameter such as calcaneal eversion may be too narrow a view and, as we have seen, produce mixed results. It may be that the hip or ankle is affected by footwear, and these joints cause deviations at the knee, with the knee being the site of the injury. By analysing how the knee interacts with other joints using a holistic or coordination analysis, we may then present a reason, for example, for the number of so many knee injuries in running. Then we may answer the question: can footwear reduce the risk of these injuries? The holistic analyses may also help reveal functional groups of runners to identify which runners are more or less susceptible to injury.

what he termed the 'preferred movement path'. He suggested that there is a subject-and task-specific locomotion pattern that is determined by many factors and that this preference for a particular motion path may explain why shoes have little effect on lower extremity kinematics. This new paradigm has given researchers 'food for thought' and has led to the new assessment tools such as how footwear may affect the determination of a runner's deviation from the runner's preferred path.
A runner's 'preferred movement path' may be interpreted in many different ways, one of which relates to the movement of the whole body system rather than a single joint movement. Joints and segments of the lower extremity interact to produce a smooth and efficient movement path. Thus, for an individual, there will be a movement path unique to them and, in Nigg's words, would result in significant muscle adaptations if there are deviations from the ideal path. Such an analysis of the coordination of the body when running gives rise to analysis techniques based on Dynamical Systems Theory (Hamill, van Emmerik, Heiderscheit, & Li, 1999). It may be this systems approach could lead to a more fruitful evaluation of running footwear that what was used in the past.
As an example, Taunton et al. (2002) identified the knee as the most prevalent site for running injuries. However, focusing on a single parameter such as calcaneal eversion may be too narrow a view and, as we have seen, produce mixed results. It may be that the hip or ankle is affected by footwear, and these joints cause deviations at the knee, with the knee being the site of the injury. By analysing how the knee interacts with other joints using a holistic or coordination analysis, we may then present a reason, for example, for the number of so many knee injuries in running. Then we may answer the question: can footwear reduce the risk of these injuries? The holistic analyses may also help reveal functional groups of runners to identify which runners are more or less susceptible to injury.

Conclusions
While running footwear can be a risk factor for injury, it is not the 'main' or most significant factor. The research conducted in the past has produced excellent footwear but we cannot state definitively that footwear has reduced the risk of running injuries.

Disclosure statement
No potential conflict of interest was reported by the author.

Introduction
When looking for a new pair of running or walking shoes, the customer is overwhelmed by the possible choices.
Advertisements with commitments of better stability, lower impact forces next to increasing speed, distance and performance, less fatigue, and reduction of injuries are legion. Although those promises, still many running-and walking-related injuries occur. Not all can be related to the footwear since the aetiology of those injuries is multifactorial (Hreljac, 2004). However, little is known about the relationship between the consumer behaviour towards footwear and the development of those injuries.

Purpose of the study
The purpose of this investigation was to investigate if consumer behaviour towards footwear is a risk factor for lower extremity injuries.

Methods
The consumer behaviour towards running and walking footwear was investigated in 300 runners and 280 walkers by means of a baseline questionnaire which included 28 questions concerning the basic decisions and influencing factors. The basic decisions imply those choices that a runner/walker makes before he gets to the store, including the place of acquisition, whether or not undergoing a gait analysis, the price, a second-hand buy, the replacement after a specific distance or time, the reason of acquisition, the influence of advice of others, and impulsiveness. The influencing factors include colour, model, material, closure mechanism, presence of specific properties, price, quality, price-quality ratio, sales and discounts, brand, fashion, advertisement, comfort, necessity, sport specificity, right fitting, technology, and store service. Information on injuries sustained during a 24-week period after the baseline questionnaire was obtained using a 2-weekly questionnaire. A running or walking injury was defined as a self-reported injury on muscles, joints, tendons, and/or bones of the lower extremities that the participant attributed to running or walking. The problem had to be severe enough to cause a reduction in the distance, speed, duration or frequency of running or walking, or treatment of the injury was carried out. Binary logistic regression analysis was used to identify risk factors for lower extremity injuries in the consumer behaviour.

Results
Data of 104 walkers and 104 runners who responded to all injury questionnaires and who did not change footwear during the follow-up period was used for further analysis. Forty-nine (24%) subjects suffered a self-reported lower extremity injury. Thirty-five injuries occurred in runners and 14 among the walkers. Logistic regression analysis showed that a gait analysis before buying footwear, not caring for the model or the closure mechanism of the shoe and feeling very much concerned about price-quality ratio were risk factors for lower extremity injuries. Buying shoes specific for the requested sport activity and buying the correct size decreased the risk.

Discussion and conclusion
The results of this study showed that buying footwear after a gait analysis increased the risk for a lower extremity injury in runners and walkers. Runners might think that after a gait analysis, they are protected against injuries but the contrary seems to be true. A possible explanation might be that they presume to have the perfect shoes with optimal protection against injuries after such an analysis. Consequently, they become unconsciously imprudent and take more risks. Another explanation might be that those subjects who have an injury history are more likely to undergo a gait analysis, hoping not to develop any further injuries by procuring individually adapted shoes. But in fact, they have a higher risk of developing another injury because injury history is the most predisposing factor for a new injury.
Next to that, results of this study also showed that not caring for the model and the closure mechanism of the shoe were risk factors for a lower extremity injury, while buying sport-specific shoes and correct size were rather protective against developing injuries. Therefore, runners and walkers should pay attention to the model, the sport specificity, the closure mechanism, and the correct size when buying footwear.
Since consumer behaviour towards footwear is a risk factor for lower extremity injuries, physical therapists and other medically trained co-workers might assist runners/ walkers in buying correct footwear to prevent these injuries.

Disclosure statement
No potential conflict of interest was reported by the authors.