Metabolic Demands, Center of Mass Movement and Fractional Utilization of VO2max in Elite Adolescent Tennis Players During On-Court Drills

The aim of the study was to investigate the exercise intensity and energy expenditureduring four types of on-court tennis drills. Five female andfive male tennis playersparticipated in the study (age: 17±2 years; ̇VO2max: 54±6 ml·kg−1·min−1).Anthropometric measures were taken for each player and, on separate days, each playerperformed (i) treadmill running to determine ̇VO2maxand (ii) four different tennis drills(Drill1-4) during which ̇VO2, blood lactate concentration, ratings of perceived exertion(RPE 6–20), and displacement of center of mass (m) using 3D kinematics were recorded.The drills were designed to simulate match play with 90 s of rest between each drill.A repeated two-way ANOVA was used for physiological and biomechanical data andFriedman’s test for RPE using<α0.05. Fractional utilization of ̇VO2maxwas greatestduring Drill1 81.8±7.0% and lowest during Drill4 72.4±5.2% (p<0.001) with nodifference between sexes (p>0.05). The highest energy expenditure was during Drill1and lowest during Drill4 (77±15 and 49±11 kcal, respectively,p<0.05). Energyexpenditure per meter for Drill1–Drill4 was subsequently reduced for each drill with 10.5±2.1, 9.9±2.2, 7.6±1.7, and 8.0±1.6 J·kg−1·m−1(p<0.01). There were nointeraction effects for any of these variables. RPE (6–20) and blood lactate concentrationpost Drill1–Drill4 were 17.5, 15.5, and 13.0 (overall, legsand arms,p<0.001) and 5.9±2.0, 4.9±1.9, 5.6±2.0, and 5.0±2.2 mmol·l−1(p<0.05). The findings of this studydemonstrate that the on-court tennis drills performed hereare suitable for high intensitytraining in junior tennis players. The energy expenditure per minute is comparable tosimilar sports whereas the energy expenditure per meter is notably greater.Tennis Research and Performance Grou