Please cite this article in press as: Bergstra SA, et al. Running with a minimalist shoe increases plantar pressure in the forefoot region of healthy female runners. J Sci Med Sport (2014), http://dx.doi.org/10.1016/j.jsams.2014.06.007 ARTICLE IN PRESS G Model JSAMS-1046; No. of Pages 6 Journal of Science and Medicine in Sport xxx (2014) xxx–xxx Contents lists available at ScienceDirect Journal of Science and Medicine in Sport journal h om epage: www.elsevier.com/locate/jsams Original research Running with a minimalist shoe increases plantar pressure in the forefoot region of healthy female runners S.A. Bergstra a , B. Kluitenberg b , R. Dekker b,c , S.W. Bredeweg b , K. Postema c , E.R. Van den Heuvel d , J.M. Hijmans c , S. Sobhani c,∗ a Centre for Human Movement Sciences, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands b Center for Sports Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands c Department of Rehabilitation Medicine, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands d Department of Epidemiology, University Medical Center Groningen, University of Groningen, Groningen, The Netherlands a r t i c l e i n f o Article history: Received 30 January 2014 Received in revised form 9 June 2014 Accepted 11 June 2014 Available online xxx Keywords: Overuse injury Footwear Barefoot running Stress fracture Landing strategy a b s t r a c t Objectives: Minimalist running shoes have been proposed as an alternative to barefoot running. However, several studies have reported cases of forefoot stress fractures after switching from standard to minimalist shoes. Therefore, the aim of the current study was to investigate the differences in plantar pressure in the forefoot region between running with a minimalist shoe and running with a standard shoe in healthy female runners during overground running. Design: Randomized crossover design. Methods: In-shoe plantar pressure measurements were recorded from eighteen healthy female run- ners. Peak pressure, maximum mean pressure, pressure time integral and instant of peak pressure were assessed for seven foot areas. Force time integral, stride time, stance time, swing time, shoe comfort and landing type were assessed for both shoe types. A linear mixed model was used to analyze the data. Results: Peak pressure and maximum mean pressure were higher in the medial forefoot (respectively 13.5% and 7.46%), central forefoot (respectively 37.5% and 29.2%) and lateral forefoot (respectively 37.9% and 20.4%) for the minimalist shoe condition. Stance time was reduced with 3.81%. No relevant differences in shoe comfort or landing strategy were found. Conclusions: Running with a minimalist shoe increased plantar pressure without a change in landing pat- tern. This increased pressure in the forefoot region might play a role in the occurrence of metatarsal stress fractures in runners who switched to minimalist shoes and warrants a cautious approach to transitioning to minimalist shoe use. © 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved. 1. Introduction Running is a popular sport among adults. However, research into running injuries has shown an overall incidence of lower extrem- ity injuries between 19.4% and 79.3%. 1 In the last three decades running shoes with a cushioned heel and motion control features have been promoted to prevent these injuries, 2–4 however no evi- dence has established yet that injury rates among runners have declined accordingly. 5 This led to an increased interest in barefoot running. 6,8,9 When the dynamics of barefoot running are compared to run- ning with standard running shoes, findings include a change in ∗ Corresponding author. E-mail address: sobhan132@gmail.com (S. Sobhani). landing strategy from a rearfoot to a midfoot/forefoot strike, which leads to a reduction in stride length, a higher step frequency, more plantarflexion and higher ankle compliance. 5–7 Several authors suggested that these changes in running biomechanics lead to a lower impact load during loading phase and a more distributed force, which might eventually reduce the risk of running overuse injuries (e.g. knee overuse injuries and heel and tibial stress fractures). 6,10,11 Despite these possible advantages, barefoot running without shoe protection can have disadvantages such as risk of skin wounds (e.g. due to sharp objects on the road) or discomfort in cold weather. Therefore minimalist running shoes have been developed to mimic barefoot running, while at the same time offering protection to the feet. 8 Several running companies such as Vibram Fivefingers and Merrell 12,13 have claimed on their websites that running with mini- malist shoes is equal to barefoot running. These minimalist running http://dx.doi.org/10.1016/j.jsams.2014.06.007 1440-2440/© 2014 Sports Medicine Australia. Published by Elsevier Ltd. All rights reserved.