"A New Approach to Assess the Physical Demands of Young Tennis Players: Inertial Movement Analysis. Preliminary Data"

Abstract

In recent years, there has been an increased interest around the use of wearable microsensor technology in order to improve the knowledge about activities patterns such as accelerations, decelerations, jumps and changes of direction. This complex information is a result of accelerometers, magnetometers and gyroscopes and is processed with an advanced algorithm to provide Inertial Movement Analysis (IMA). This technology may also calculate the magnitude and the direction of an agility action, classifying events within intensity and direction. Therefore, the aim of this study was to describe the physical profile of elite young tennis players focusing in the “IMA” patterns. Twenty female young high-level tennis players took part in the study (14.3 age ± 0.8 years). All tennis players were tracked at least in two matches-play (n=62) on hard court. Twelve Portable GPS devices (Minimax X S4, Catapult Innovations) operating at a sampling frequency of 10 Hz were used to collect velocity data. The GPS unit contains a tri-axial piezoelectric linear accelerometer (Kionix: KXP94) sampling at a frequency of 100 Hz. The most common axis of movement was the vertical (V_axis:39.3 ±1.9%). On the other hand, lateral displacement were the most common movements of tennis players (right:6.4±1.2 effort· min 1; left:6.3±1. effort· min 1). Furthermore, low accelerations were the most common acceleration pattern in tennis (low accelerations: 7.4±2.3 effort·min-1), whereas, the high intensity accelerations (>1.0 m·s-2) were the less frequent (high accelerations: 5.1±1.6 effort·min-1). Therefore, further literature should focus on “IMA” patterns to improve tennis players’ performance. .