The purpose of the master's thesis was to check the influence of different surfaces and speeds on the biomechanical characteristics of running, and within this evaluate the sensitivity and reliability of the commercial RunScribe™ sensor. In the study, 24 runners performed repeated runs of 200 m on grass, asphalt and macadam surfaces at a predicted competitive speed of 21 km. In addition, a measurement was made on the asphalt surface with the predicted competitive speed of the 5 km run. Contact time, flight time, stride length, stride frequency, ground reaction braking force and vertical ground reaction force, as well as pronation angle and angular velocity were recorded. Data collection between individual visits was repeated within 7 to 10 days. The reliability of the measurements was checked using the method of repeated visits. Coefficient of variance (CV), standard error of measurement, interclass correlation coefficient (ICC 2,1 and 2,k) and systematic effect (analysis of variance for repeated measures – level of statistical significance, p < 0.05) were used as measures of reliability. Data from the first visit were used for sensitivity measures. The comparison between types of running surface and different speeds in the selected biomechanical parameters was checked with a two-way t-test for dependent samples, where we additionally calculated the effect size. All results were interpreted as statistically significant at a risk level of 5 %. Intra visit reliability was excellent for all variables at a competitive speed of 21 km (ICC: asphalt: 0.90 0.99; macadam: 0.94 1.00; grass: 0.92 1.00). The coefficient of absolute variation was acceptable in all conditions (KV < 10%). Inter visit reliability was good or high for all variables considered (ICC ≥ 0,85). The difference in running speed did not have a statistically significant effect on the selected parameter (ES = 0,04 – 0,38). Sensitivity tests between individual surfaces showed statistically significant differences and medium to high effect size for only a few parameters.
However, based on the limitations of our research, we cannot evaluate the sensitivity of the sensor and the degree of validity of the measurements. Based on the others and our study, we can conclude that the RunScribe™ sensor is a reliable tool for evaluating spatio-temporal and kinematic parameters as well as basic kinetic parameters of running technique, but their validity is questionable. In the future, it will be necessary to investigate the sensitivity of the sensor and the validity of the measurements in comparison with the measurements of the gold standard.
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