Reliability of horizontal force–velocity–power profiling during short sprint-running accelerations using radar technology

Abstract

Radar technology can be used to perform horizontal force–velocity–power profiling during sprint-running. The aim of this study was to determine the reliability of radar-derived profiling results from short sprint accelerations. Twenty-seven participants completed three 30 m sprints (intra-day analysis), and nine participants completed the testing session on four separate days (inter-day analysis). The majority of radar-derived kinematic and kinetic descriptors of short sprint performance had acceptable intra-day and inter-day reliability [intraclass correlation coefficient (ICC) ≥ 0.75 and coefficient of variation (CV) ≤ 10%], but split times over the initial 10 m and some variables that include a horizontal force component had only moderate relative reliability (ICC = 0.49–0.74). Comparing the average of two sprint trials between days resulted in acceptable reliability for all variables except the relative slope of the force–velocity relationship (S _Fvrel; ICC = 0.74). Practitioners should average sprint test results over at least two trials to reduce measurement variability, particularly for outcome variables with a horizontal force component and for sprint distances of less than 10 m from the start.

Keywords:

• Speed test
• team sports
• rugby

Acknowledgements

The authors would like to acknowledge the study participants and all research assistants involved in the data collection process. The authors would also like to acknowledge the work of Matt Brughelli and Matt Cross in developing the custom-made Labview program used in the current study and Scott Brown for guidance with the radar analysis.