Sprint mechanical properties of professional rugby league players according to playing standard, age and position, and the association with key physical characteristics

BACKGROUND: This study determined the influence of playing standard, age, and position on the horizontal force-velocity (FV) properties of rugby league players, and the association with other characteristics. METHODS: This observational study used a cross-sectional design with a range of physical characteristics recorded from 132 players from 5 Super League clubs. Sprint data was used to derived theoretical maximal force (F0) and velocity (V0), power (Pmax), maximal rate of force (RFmax) and the rate of decrease in RFmax (DRF). Differences between playing standard, age groups and playing positions were determined (P value and standardised mean difference (SMD) along with correlational analysis to assess the relationship between FV properties and key physical characteristics. RESULTS: Senior players reported lower split time (SMD = -0.26--0.59, P =0.002-0.017), absolute F0, Pmax and V0 (SMD = 0.47-0.78, P 26 years (SMD = -0.40, P=0.002). Hit-up forwards were slower than outside backs (SMD = -0.30--0.89, P