Repeated-Sprint Performance, Locomotor Profile and Muscle Oxygen Uptake Recovery: Effect of Training Background

The aim of the present study was to examine the respective importance of locomotor profile and muscle oxygen uptake (mV O-2) recovery on repeated-sprint ability (RSA) and overall repeated-sprint performance. 11 sprint- (STR) and 10 middle-distance-trained (MDTR) athletes (20.8 +/- 4.0 yr) performed an incremental test and a 40-to-50-m sprint to estimate their maximal aerobic (MAS) and sprinting (MSS) speeds. They also performed 6x30-m sprints, departing every 30 s, where mean (RSmean) sprint time was calculated. Muscle oxygenation (Near-infrared spectroscopy, NIRS, [Hb(diff)]) was measured for similar to 4 min post test. The mean response time of [Hb(diff)]-mV O-2 recovery (monoexponential curve fitting, MRT[Hb(diff)]-mV O-2) was calculated. Compared with MDTR, STR presented faster MSS (+11.4 +/- 6.7%, with 99% chances to observe a substantially greater value) and RSmean (-3.7 +/- 5.4%, 78%), but slower MAS (-15.8 +/- 8.0%, 100%) and MRT[Hb(diff)]-mV O-2 (+46.2 +/- 31.7%, 96%). RSmean was largely correlated with MSS [r=-0.83 (90%CL, -0.92;-0.67)], but neither with MAS [r=-0.12 (-0.47;0.25)] nor MRT[Hb(diff)]-mV O-2 [r=-0.27(-0.58;0.11)]. RSmean adjusted for MSS (which indirectly reflects RSA) was largely correlated with both MAS [r=0.51(0.18;0.74)] and MRT[Hb(diff)]-mV O-2 [r=0.53(0.20;0.75)]. While a fast mV O-2 recovery is associated with an improved RSA, MSS remains of primary importance for overall repeated-sprint performance (i.e., RSmean).