Methods of assessing, monitoring and improving strength and ballistic performance in highly trained rugby union players

by Daniel Travis Williams McMaster

Institution: AUT University
Year: 0
Keywords: Force; Velocity; Power
Record ID: 1317177
Full text PDF: http://hdl.handle.net/10292/7333


Strength and ballistic qualities are vital to excelling in contact team sports, such as rugby. The assessment, development, retention and decay of these qualities are of great interest, as this information can be utilised by strength and conditioning coaches to better inform and guide the yearly training plan. The overall aim of this project was to develop innovative and effective strength and ballistic assessment batteries that provide an in depth athlete profile through novel analytical approaches to improve current methods of assessment, monitoring and programming in the semi-professional rugby union. In study one, measurement system validation (Chapter 4) outcomes revealed an inconsistency between peak force (PF), peak velocity (PV) and peak power (PP) between the force plate and accelerometers (hip and bar attachments) during vertical jumps (VJ). Both accelerometer attachments were reliable for assessing PF (ICC = 0.80 – 0.83), but were low to moderately reliable for monitoring PV and PP (ICC = 0.35 – 0.77); therefore, subsequent studies in this PhD utilised force plate technology and linear position transducers as the primary means of assessing ballistic performance. In Chapter five, bench throw (BTH) and VJ incremental relative load (body mass-VJ, 15, 30, 45, 60 and 75% 1RM) profiles were also validated using a linear position transducer. The BTH (ICC > 0.80; CV < 11 %) and VJ (ICC > 0.75; CV < 11%) protocols described were relatively stable and reliable within and across testing sessions; and in turn deemed appropriate to monitor BTH and VJ PP, PF and PV adaptations in subsequent studies. The force-velocity profiling data was further analysed to predict maximum BTH and VJ force (Fmax) and velocity (Vmax) to provide a more holistic representation of these ballistic movements. In chapters six and seven, the effects of strength and sprint ability on the previously validated BTH and VJ force-velocity-power profiles were assessed. The comparative statistical analysis illustrated that stronger players produced higher BTH Pmax (14%) and Fmax (17%) and higher VJ Fmax (10%); whereas faster players produced greater VJ Pmax (14%) and Vmax (11%). These findings could be useful to better inform programming of individual and group mechanical efficiencies and deficiencies. The next three chapters used the major findings of these validation and comparative studies to assess the effects of training, detraining and a competitive season on the performance profile. Firstly, the five week complex training (Chapter 8) interventions (strength + heavy ballistic [SHB]; strength + light ballistic [SLB]) herein elicited positive adaptations in 1RM bench press (4 – 9 %) and 1RM squat (9 – 12 %); as well as reductions in 10, 20 and 30 m sprint times (-1 to -2%). SHB training caused positive shifts in Fmax (6 to 10%) and Pmax (12 to 46%); whereas the SLB training caused increases in Vmax (15 to 68%) and Pmax (15 to 36%). Findings indicate that acute SHB and SLB training can be implemented to elicit positive adaptations in…