Sports require specific strength and explosiveness characteristics, and in order to enable training monitoring of athletes, the Portuguese Athletics Federation, in collaboration with the Polytechnic Institute of Leiria (Portugal), and the team of Paulo Miranda-Oliveira, designed a methodology for assessing crouch jumps (CMJs) using the IMU to analyze the performance of athletes in the build-up phase of the force, the height of the jump, and the Modified Reaction Strength Index (RSImod).

The team developed a device that contains a 9-axis IMU-accelerometer (±16g), gyroscope (±2000dps), and magnetometer (±4900µT), with a data sampling rate of 300Hz.The connection between the IMU and the laptop was made via Wifi. Meanwhile, the experimental tests were performed on a Force Plate (FP) and the data collected from the Force Plate was used as a baseline for comparison.

A total of eight high-level athletes (six males and two females) participated in the test, none of whom had a documented injury in the six months prior to the test. The research team placed an IMU fixation on the athlete's fifth lumbar vertebra (L5).

Schematic of IMU location, fifth vertebra (L5)

Each athlete performed 3-5 CMJ jumps per set, with 1 minute between each jump, for a total of 30 CMJ jumps.

Statistical results of force plate FP and IMU in different phases of jumping

The statistical results of IMU and FP show that they have similar results in terms of positive pulse phase time, negative pulse phase time, lag time, etc. Meanwhile, they also have similar results in terms of jumping height, maximal force, minimal force, RSImod, etc. The device is simple and easy to use, which can help coaches and athletes to monitor and control their training. At the same time, the device is simple and easy to use, which can help coaches and athletes to monitor and control the training, improve the systematic training, and improve the training level at the same time.

Original paper: https://www.mdpi.com/1424-8220/22/19/7186