Hendrik Enders1, Vinzenz von Tscharner2, Benno M Nigg2. 1. Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada. Electronic address: henders@kin.ucalgary.ca. 2. Human Performance Laboratory, Faculty of Kinesiology, University of Calgary, Calgary, AB, Canada.
Abstract
OBJECTIVES: To characterize soft tissue vibrations during running with a preferred and a non-preferred strike pattern in shoes and barefoot. DESIGN: Cross-sectional study. METHODS: Participants ran at 3.5 m s(-1) on a treadmill in shoes and barefoot using a rearfoot and a forefoot strike for each footwear condition. The preferred strike patterns for the subjects were a rearfoot strike and a forefoot strike for shod and barefoot running, respectively. Vibrations were recorded with an accelerometer overlying the belly of the medial gastrocnemius. Thirteen non-linearly scaled wavelets were used for the analysis. Damping was calculated as the overall decay of power in the acceleration signal post ground contact. A higher damping coefficient indicates higher damping capacities of the soft tissue. RESULTS: The shod rearfoot strike showed a 93% lower damping coefficient than the shod forefoot strike (p<0.001). A lower damping coefficient indicates less damping of the vibrations. The barefoot forefoot strike showed a trend toward a lower damping coefficient compared to a barefoot rearfoot strike. Running barefoot with a forefoot strike resulted in a significantly lower damping coefficient than a forefoot strike when wearing shoes (p<0.001). The shod rearfoot strike showed lower damping compared to a barefoot rearfoot strike (p<0.001). While rearfoot striking showed lower vibration frequencies in shod and barefoot running, it did not consistently result in lower damping coefficients. CONCLUSIONS: This study showed that the use of a preferred movement resulted in lower damping coefficients of running related soft tissue vibrations.
OBJECTIVES: To characterize soft tissue vibrations during running with a preferred and a non-preferred strike pattern in shoes and barefoot. DESIGN: Cross-sectional study. METHODS:Participants ran at 3.5 m s(-1) on a treadmill in shoes and barefoot using a rearfoot and a forefoot strike for each footwear condition. The preferred strike patterns for the subjects were a rearfoot strike and a forefoot strike for shod and barefoot running, respectively. Vibrations were recorded with an accelerometer overlying the belly of the medial gastrocnemius. Thirteen non-linearly scaled wavelets were used for the analysis. Damping was calculated as the overall decay of power in the acceleration signal post ground contact. A higher damping coefficient indicates higher damping capacities of the soft tissue. RESULTS: The shod rearfoot strike showed a 93% lower damping coefficient than the shod forefoot strike (p<0.001). A lower damping coefficient indicates less damping of the vibrations. The barefoot forefoot strike showed a trend toward a lower damping coefficient compared to a barefoot rearfoot strike. Running barefoot with a forefoot strike resulted in a significantly lower damping coefficient than a forefoot strike when wearing shoes (p<0.001). The shod rearfoot strike showed lower damping compared to a barefoot rearfoot strike (p<0.001). While rearfoot striking showed lower vibration frequencies in shod and barefoot running, it did not consistently result in lower damping coefficients. CONCLUSIONS: This study showed that the use of a preferred movement resulted in lower damping coefficients of running related soft tissue vibrations.
Authors: Marie-Caroline Play; Robin Trama; Guillaume Y Millet; Christophe Hautier; Marlène Giandolini; Jérémy Rossi Journal: Sports Med Open Date: 2022-10-22