G-40 Free Communication/Poster - Running Mechanics Saturday, June 4, 2016, 7:30 AM - 11:00 AM Room: Exhibit Hall A/B
Asymmetry of loading has been related to running injuries. Studies within our lab suggest that symmetry of loading increases when habitually shod (SH) individuals run barefoot (BF), suggesting that sensory input may play a role. However, it is unclear if this is true of habitually BF runners.
PURPOSE: To compare the Symmetry Index between habitual SH and habitual BF runners.
METHODS: 12 habitually SH runners (10 M, aged 35.6 ± 8.4 yrs) and 11 habitually BF runners (10 M, 42.5 ± 11.4 yrs) who run at least 10 mpw were recruited in this ongoing study. All subjects ran on an instrumented treadmill at 2.62 m/s while force was sampled at 1500 Hz. Vertical force peak (VP), average (ALR) and instantaneous (ILR) loadrates, and stance time (ST) were extracted from each stance phase and averaged over 10 strides. The symmetry index (SI) was calculated between the average for each variable for the right (R) and left (L) sides. A higher SI value indicates greater asymmetry. SI values were compared between habitually SH and habitually BF subjects using an independent t-test (p-value < 0.05).
RESULTS: Results for loading variables on the L and R sides, as well as the calculated SI values are reported in Table 1. Note the lower values for ALR and ILR in the BF condition. However, values between L and R sides are similar in all variables for both SH and BF conditions. This resulted in no significant differences in SI between SH and BF conditions.
CONCLUSION: Contrary to our findings in novel BF conditions, these preliminary data suggest that habitual BF runners do not exhibit greater symmetry than habitually shod runners. It is possible that once habituated to being BF, sensory input has less of an effect on gait. We will continue to examine this as we continue our subject recruitment.