A comparison between a new foot-mounted inertial measurement system and a local positioning system in amateur futsal

This study aimed to 1) establish the level of agreement between a foot-mounted inertial measurement system (PlayerMaker™) and a local positioning system (Catapult ClearSky™) for time-motion analysis variables in recreational futsal, (2) determine the level of agreement between the technical futsal performance variables of the foot-mounted inertial measurement units and video analysis (Catapult Vision), and 3) assess the match-to-match variability of the futsal players’ physical and technical performances throughout recreational games of futsal. Twenty-eight male participants (mean ± SD age: 32.8 ± 11.7 years; stature: 179.6 ± 8.8 cm; mass: 83.4 ± 12.2 kg), each wearing a pair of PlayerMaker™ sensors and a Catapult ClearSky™ S7 Vector unit, played ten-minute games of five a side recreational futsal across the data collection period. The level of agreement for total distance covered (meters) between the PlayerMaker™ sensors (790 ± 107) and Catapult ClearSky™ (780 ± 104) was measured. The maximum velocity (meters per second) metric was quantified PlayerMaker™ (5.3 ± 0.6) and Catapult ClearSky™ (5.3 ± 0.7) to represent the level of agreement between the two systems. The level of agreement for the number of ball releases per futsal game was analysed in the present study between PlayerMaker™ (8.1 ± 5.9) and video analysis (16.1 ± 5.1). The level of agreement between PlayerMaker™ (18.5 ± 6.5) and video analysis (37.3 ± 5.3) for the number of ball touches per futsal game was also analysed. This study recommends the PlayerMaker™ inertial measurement system is utilised as a cheaper alternative to an LPS for quantifying time-motion analysis variables indoors. The PlayerMaker™ sensors might serve as a valid and reliable alternative to an LPS, but sporting practitioners must remain aware of the shortcomings of the system or of the various factors that compromise the quality of data produced by it.