Effects of running with minimal and conventional footwear in habitual and non-habitual users: a musculoskeletal simulation and statistical parametric mapping based approach.

Abstract

The current investigation examined running biomechanics in minimal and conventional footwear in two groups of runners who either ran habitually in minimal footwear (habitual minimal footwear users) or habitually in conventional footwear (non-habitual minimal footwear users). We studied ten male non-habitual minimal footwear users and ten male habitual minimal footwear users, who were required to complete ≥35 km per week of training. Lower extremity joint loading was explored using a musculoskeletal simulation approach. Differences between conditions were examined using statistical parametric mapping and 2 × 2 mixed ANOVA. This study revealed via the strike index that minimal footwear caused a more anterior contact position in both groups (habitual: minimal = 61.68% & conventional = 46.48%/non-habitual: minimal = 33.79% & conventional = 22.61%), although non-habitual runners still adopted a rearfoot strike pattern. In addition, in non-habitual users minimal footwear increased tibial accelerations (habitual: minimal = 6.35g & conventional = 7.06g/non-habitual: minimal = 9.54g & conventional = 8.16g), loading rates (habitual: minimal = 105.44 BW/s & conventional = 105.97 BW/s/non-habitual: minimal = 293.00 BW/s & conventional = 154.36 BW/s) and medial tibiofemoral loading rates (habitual: minimal = 196.17 BW/s & conventional = 274.96 BW/s/non-habitual: minimal = 274.96 BW/s & conventional = 212.57 BW/s). Furthermore, minimal footwear decreased patellofemoral loading in both habitual (minimal = 0.28BW·s & conventional = 0.31 BW·s) and non-habitual (minimal = 0.26 BW·s & conventional = 0.29 BW·s) users. Finally, Achilles tendon loading was larger in minimal footwear and in habitual runners (habitual: minimal = 0.79 BW·s & conventional = 0.71 BW·s/non-habitual: minimal = 0.71 BW·s & conventional = 0.65 BW·s) whereas iliotibial band strain rate was reduced in habitual (minimal = 28.32%/s & conventional = 30.30%/s) in relation to non-habitual (minimal = 42.96%/s & conventional = 42.87%/s) users. This study highlights firstly the importance of transitioning to minimal footwear and also indicates that post-transition may be effective in attenuating the biomechanical mechanisms linked to the aetiology of many chronic injuries.