Shoe-mounted accelerometers should be used with caution in gait retraining

Area of Science:

• Biomechanics
• Sports Medicine
• Wearable Technology

Background:

• Real-time biofeedback gait retraining effectively reduces impact loading.
• Laboratory studies often use tibia sensors, but commercial options are frequently shoe-mounted.
• The accuracy of shoe-mounted sensors for gait retraining interventions needs further investigation.

Purpose of the Study:

• To compare impact loading parameters measured by shoe-mounted versus tibia sensors before and after gait retraining.
• To assess the correlation between peak positive acceleration at the shoe (PPA_S) and tibia (PPA_T) with vertical loading rates.
• To evaluate the effectiveness of visual biofeedback walking and running retraining using different sensor placements.

Main Methods:

• 24 participants underwent 2-week visual biofeedback walking retraining.
• 14 participants underwent 2-week visual biofeedback running retraining.
• Impact loading parameters (PPA_S, PPA_T, vertical loading rates) were measured using both shoe-mounted and tibia sensors.

Main Results:

• Walking retraining reduced PPA_S but not PPA_T or vertical loading rates.
• Running retraining reduced PPA_T and vertical loading rates.
• PPA_S was significantly higher than PPA_T, indicating a decoupling effect, and PPA_S did not correlate with vertical loading rates, unlike PPA_T.

Conclusions:

• Commercial shoe-mounted sensors may have limitations in accurately capturing gait modifications during retraining.
• Tibia sensors provide a more reliable measure of impact loading changes relevant to injury risk.
• Gait retraining effectiveness may differ depending on sensor placement and activity type (walking vs. running).