COMPARING PEAK ANTERIOR-POSTERIOR GROUND REACTION FORCES BETWEEN RECREATIONAL RUNNERS IN MAXIMAL AND TRADITIONAL SHOES

L. Bartel, A. Traut, C. Pollard, J. Hannigan Oregon State University-Cascades, Bend, OR Peak posterior ground reaction force (PPGRF) during running results from rapid deceleration or “braking” and is a biomechanical variable associated with injury. Peak anterior ground reaction force (PAGRF) represents the forward propulsion force during running. Previous research has suggested that maximal shoes can increase vertical ground reaction force metrics related to injury, but there is little research on how maximal shoes affect anterior-posterior ground reaction forces, and whether this may depend on an individual’s shoe preference. PURPOSE: To compare PPGRFs and PAGRFs between maximal and traditional shoes in both runners that prefer traditional shoes and runners that prefer maximal shoes. METHODS: 30 participants were recruited (18 traditional-preferred and 12 maximal-preferred shoe runners) for a single testing session. Three-dimensional lower extremity biomechanics were captured during running using a 10-camera motion capture system and three force plates in two shoe conditions: maximal shoes (rearfoot: 37mm, forefoot: 33mm) and traditional shoes (rearfoot: 32mm, forefoot: 22mm). Variables of interest included peak posterior and peak anterior ground reaction forces. For both variables, a mixed-effects ANOVA compared data between shoes and between shoe preference groups (α = .05). RESULTS: No interaction effect or main effect of preference were noted for either variable. For the main effect of shoe, PAGRF values were lower in maximal shoes (.296 .062 BWs) compared to traditional shoes (.319 .062 BWs, p \u3c .001). PPGRF values were trending but not significantly different between maximal shoes (-.416 ± .101 BWs) and traditional shoes (-.403 .101 BWs, p = .055). CONCLUSION: Our findings suggest that participants who preferred maximal running shoes exhibited lower PAGRF values which could conclude that the thicker, “rocker-shaped” midsole of the maximal shoe requires less propulsion force. PPGRF values in the maximal shoe were trending but not significantly lower, which may increase risk of injury related to deceleration. Further research is needed to confirm these conclusions. Supported by OSU-Cascades Layman Fellowship Awar