Introduction: Basketball is a sport characterized by an intermittent game model of which short shuttle runs (SR) are typical components. Buglione and di Prampero (2013) measured the energy cost (EC) of SR over the distances of 10 and 20 m and showed that EC increases with the shuttle speed and decreases with the shuttle distance; no data are reported in the literature over shorter distances. Thus, the aim of this study was to assess the EC of short SR (5 m) at different shuttle speeds. Methods: A descriptive design was used in this study. Ten male basketball players (age 24 ± 1.5 years, body mass 80 ± 8.6 kg, height 1.84 ± 5.8 m) performed a preliminary test on a treadmill in order to estimate the EC of "linear running" (at a speed of 10 km/h). They were then asked to perform 10 SR (with 30 seconds of passive recovery in-between) over a distance of 5+5 m with 180° change of direction; these experiments were repeated at different speeds (2, 2.5, 3, 3.5 m/s). During both protocols oxygen consumption (V`O2) was determined on a breath-by-breath basis by means of a portable metabolimeter (K4b2, Cosmed, Italy) and blood lactate concentration was determined at the end of each test (Biosen C-Line, Germany). Based on these data EC (the energy expended to cover one unit distance, normalized per body mass: J/kg.m) was then calculated as proposed by Zadro et al. (2011). Results: The EC of linear running amounted to 3.96 ± 0.47 J/kg.m whereas the EC of shuttle runs was 4 to 7 times larger: 15.67 ± 2.85 J/kg.m (2 m/s), 19.20 ± 2.87 J/kg.m (2.5 m/s), 23.81 ± 4.69 J/kg.m (3 m/s), 29.42 ± 6.21 J/kg.m (3.5 m/s). Significant differences were observed in EC at the different speeds, p < 0.001, ç2 = 0.788. The relationship between EC and speed is well described by the following equation: EC = 10.12.v - 5.20, N = 39, R = 0.66, p < 0.001. Discussion: These findings confirm data reported in the literature since they show that EC increases with the shuttle speed; moreover, these data show that the EC of short SR (5 m) is larger than for the 10 and 20 m distances thus confirming that EC decreases with the shuttle distance. These findings have a practical application since they allow calculating EC of short SR (at different shuttle speeds) and thus can be utilized to develop train protocols in basketball as well as in other team sports (characterized by repeated sprints over short distances and with changes of direction).
© Copyright 2014 19th Annual Congress of the European College of Sport Science (ECSS), Amsterdam, 2. - 5. July 2014. Veröffentlicht von VU University Amsterdam. Alle Rechte vorbehalten.