Abstract
This study determined the effects of a six-week lower-limb wearable resistance training (WRT) intervention on sprint running time, velocity, and horizontal force-velocity mechanical variables. Twenty-two collegiate/semi-professional rugby athletes completed pre- and post-intervention testing of three maximal effort 30 m sprints. A radar device was used to measure sprint running velocity from which horizontal force-velocity mechanical profiling variables were calculated. All athletes completed two dedicated sprint training sessions a week for six-weeks during pre-season. The intervention (wearable resistance, WR) group completed the sessions with 1% body mass load attached to the left and right shanks (i.e. 0.50% body mass load on each limb), whilst the control group completed the same sessions unloaded. For the control group, all variables were found to detrain significantly (p ≤ 0.05) over the training period with large detraining effects (ES > 0.80) for theoretical maximal horizontal force, slope of the force-velocity profile, maximal ratio of force, index of force application, 5 and 10 m times. For the WR group, there were no significant changes to any recorded variables (all p > 0.05) and all effects of training were trivial or small (ES < 0.50). After adjustment for baseline differences, significant between group differences were found for all variables (large effects, ES > 0.80) except theoretical maximal velocity, 30 m time, and maximal velocity. The addition of light wearable resistance to sprint training during a six-week pre-season block enables the maintenance of sprint performance and mechanical output qualities that otherwise would detrain due to inadequate training frequencies.
Acknowledgements
The authors would like to thank the athletes that participated in this study and to the coaching staff for their interest in getting involved. Also, a thank you goes to Kyle Lindley, from the School of Biological and Health Systems Engineering, Arizona State University, USA for providing data processing assistance and Dr. Ken Clark from West Chester University, USA for his input and guidance throughout the course of this project. Funding for this study was provided by the Global Sport Institute at Arizona State University.
Disclosure statement
John Cronin is Head of Research for Lila but is blinded from data collection, statistical analyses and writing of article, and is typically involved in methodological design and final proofing.