Validação e replicabilidade de medidas acelerométricas para identificação das fases do salto de contramovimento

Abstract

Currently, techniques used in motion analysis have evolved in terms of data storage and processing, which are essential for understanding movement parameters. In the study of movement, vertical jump is present in various sports modalities. In this regard, the assessment of vertical jump has traditionally been performed using a force platform. However, force platforms come with a high cost, and for this reason, new possibilities have been explored to make vertical jump assessment more affordable. One of these alternatives is the use of inertial measurement units, such as commercial accelerometers, capable of analyzing and describing movement. The objective of this dissertation is to evaluate the validation and replicability of a commercial accelerometer for measuring intervals related to the phases of the countermovement vertical jump (CMJ). Fifteen participants aged between 18-40 years were evaluated. The test involved performing the countermovement vertical jump, which was analyzed using inertial sensors and a force platform. The force platform identified the phases of CMJ, while the inertial sensor aimed to identify the transient accelerometric components that could be used to identify the jump phases determined by the force platform. For each transient accelerometric component, the duration of this component was identified. Bland-Altman analysis and linear correlation were used to validate the results obtained with the accelerometer, and the intraclass correlation coefficient was used to assess the replicability of both the platform and the accelerometer for measuring CMJ-related phases. It was observed that there was a high correlation between the accelerometric measurements and the force platform measurements; however, there was a significant bias in the measurement of flight time by the accelerometer, which was longer than that measured by the force platform. Both devices showed moderate to high replicability for all measurements taken. The accelerometer proved to be a valid and replicable device for identifying the different phases of CMJ.