Energetics (and kinematics) of short shuttle runs

The energy cost of shuttle running (C netSR), over distances of 10-20 m, was reported to increase with the shuttle speed and to decrease with the shuttle distance. The aims of this study were to assess C netSR over a shorter distance (5 m), at different speeds, and to estimate the energy cost based on a simple kinematic analysis (C netK).

Ten subjects (six basketball players, BP; four non-basketball players, NBP) performed ten shuttle runs (SR) with 30 s of passive recovery in-between, over a distance of 5 + 5 m (with a 180° change of direction); these experiments were repeated at different speeds (range 2-3.5 m s(-1)). The values of average (v mean) and maximal (v max) speed during each run were determined by means of kinematic analysis and C netK was calculated as: 0.96[Formula: see text]. C netSR was calculated based on data of oxygen uptake, blood lactate concentration and distance covered.

The relationships between C (J m(-1) kg(-1)) and v (m(.)s(-1)) are well described by C netK (all subjects) = 11.76v - 13.09, R (2) = 0.853; C netSR (BP) = 11.94v - 12.82, R (2) = 0.636; and C netSR (NBP) = 14.09v - 14.53, R (2) = 0.738. Hence C netSR ≈ C netK in BP, whereas C netSR > C netK in NBP (un-familiar with this specific motor task).

The calculations proposed in this study allow to estimate C of short SR based on simple measures of v max and can be utilized to develop training protocols in basketball as well as in other team sports (characterized by repeated sprints over short distances).