The purpose of this study was to investigate the effect of different foot strike patterns during running on VALR. The purpose of this study was to investigate the effect of different foot strike patterns during running on VALR.
The participants were 20 healthy adult males. Barefoot running with RFS, MFS, and FFS was performed on a force plate at a speed of 10 km/h ± 5%. Reflective markers were attached to the lower limb, and the positions of the markers during running were measured using a three-dimensional motion analysis system. The analysis items included the first peak value of the vGRF during the right leg stance phase, the time to the first peak, and VALR. VALR was calculated by dividing the first peak value of the vGRF by the time to the peak. These variables were statistically compared between foot strike patterns. The significance level was adjusted using the Bonferroni method for post-hoc tests (α = 0.016). Additionally, Cohen's d was used to calculate the effect size.
VALR was significantly higher for RFS and MFS compared to FFS (p 0.016, ES = -2.47 to -3.68). The first peak value of vGRF was significantly higher in order of FFS, MFS and rearfoot strikes (p 0.016, ES = -1.47 to -3.74). The time to the first peak was significantly shorter in the order of rearfoot, midfoot, and forefoot strikes (p 0.016, ES = -0.66 to -3.19). Based on criteria previous research, the effect sizes indicated medium to large effects.
The result of present study clearly showed that the VALR was lowest in the FFS. Thus, from the perspective of VALR, the FFS has the lowest mechanical load. Additionally, there was a significant difference in peak values between RFS and MFS, but no significant difference was observed in VALR. These suggest that the first peak value of vGRF and VALR are different indicators.
FFS running can reduce VALR. FFS running may reduce the load on the lower limbs.
Foot strike pattern
Vertical average loading rate
