Reliability of radar-derived measures of sprint performance in female field sport athletes

Radar is commonly used to assess overground sprinting performance and estimate the force-velocity-power (FvP) mechanical variables; however, limited work has examined the reliability of these measures in female field sport athletes. This study aimed to assess the reliability of radar-derived measures, and to examine the associations between sprinting split times and the FvP. Twenty-three female rugby league and field hockey athletes (15-35 yrs, 70.2 ± 12.2 kg, 169 ± 6 cm) completed two 40 m sprints on two separate days. Split times displayed acceptable inter-day absolute reliability (CV = 0.91-2.17%) as did the FvP (CV range = 1.37-6.28%), however, relative reliability ranged from moderate to excellent (ICC_3,1 = 0.60-0.98) or poor to excellent (ICC_3,1 = 0.15-0.96), respectively. Maximal power output (P_MAX W/kg) was most associated to 0-30 m (<i>r</i> = -0.95). However, for completion time of the maximal velocity phase (CT_MVP) (20-40 m), P_MAX (W/kg) displayed a moderate association (<i>r</i> = -0.69), in comparison, power output at maximal velocity (P_VMAX W/kg) displayed a stronger association (<i>r</i> = -0.83). Utilising the fastest trial on a given day is suitable for monitoring sprinting performance, whilst correlations between split-times and the FvP in the current study provide important insights into the sprinting mechanics of female field sport athletes.