Electromyographic Examination Of Hex Bar Deadlift Variations Differentiated By Starting Knee And Torso Angles

Abstract

Certain anthropometric, spatiotemporal and kinematic characteristics can contribute to 100-meter sprint performance. However, it is unclear how these are different by gender for medalists and non-medalists in elite level events such as the USA Olympic Trials. PURPOSE:The purpose of this study was to analyze differences on specific anthropometric, spatiotemporal and kinematic data at 80-meters by gender for international level medalists and non-medalists. METHODS: 38 sprinters (19 males, 19 females) who made the 100-meter final or semifinal in the 2014-2019 United States National Championships were included in this study. Anthropometric data was collected using a tape measure. High speed video (300 Hz, Casio EXILM Pro EX-F1), taken at 80-meters into the 100-meter race, and kinematic software were used to collect sagittal plane kinematic variables. Group differences were assessed using a series of one-way ANOVAs. RESULTS: In males, leg length (0.93 ± 0.02m, 0.95 ± .01m; p < 0.05) and average contact time (0.085 ± 0.004s, 0.094 ± 0.007s; p < 0.01) were significantly shorter while velocity (11.50 ± 0.43m/s, 10.83 ± 0.33m/s; p < 0.01), average upper leg full extension angle (152.45 ± 7.63°, 145.63 ± 3.46°; p < 0.05), and average horizontal backward foot velocity at touchdown (8.49 ± 0.33m/s, 7.84 ± 0.47m/s; p < 0.01) were significantly larger in medalists versus non-medalists. In females, only leg length was significantly longer in medalists versus non-medalists (0.89 ± 0.03m, 0.86 ± 0.03m; p < 0.05). CONCLUSIONS: These results indicate that among females, of the variables measured here, only anthropometric characteristics seem to influence medal position.. Conversely, form and technique heavily dependent upon kinematics separate males from making a medal position. These data suggest that males may need to focus on specific kinematic outcomes in order to increase the changes of successfully making the podium in a 100-meter race.