Using a boat instrumentation system to measure and improve elite on-water sculling performance
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Sculling performance is largely determined by the magnitude and timing of blade force application, i.e. the size and shape of the sculler’s force profile. Discovering specific force profile characteristics that relate strongly with boat velocity in elite scullers, and determining how best to measure them, would allow recommendations for improved performances. The objective of this thesis was to expand knowledge regarding biomechanical measurement of sculling force profiles and to understand how the PowerLine™ boat instrumentation system could be used effectively to measure and improve elite on-water sculling performance. A literature review showed that effective rowing force profiles are large, smooth, rectangular, and have a peak force in front of the perpendicular oar position. Laboratory validity testing showed that PowerLine™ was valid for use with elite scullers, displaying a standard error of the estimate of less than 0.90 kgF for force and less than 0.5° for angle measures. On-water reliability testing established smallest worthwhile effect sizes for PowerLine™ variables for elite scullers completing 500-m trials, including 0.44% for stroke power and 0.5° for angular variables. Scullers in double sculls were more variable than single scullers so consistency in stroke power was recommended as a focus for crew scullers. Sculler analyses using PowerLine™ was better when using the average of five strokes rather than single strokes. Step wise linear regression analyses presented models for two elite scullers explaining 84% and 85% of their variation in boat velocity. However, the relationships between sculling performance and biomechanical stroke variables, including different measures of catch technique, were not consistent between elite scullers and cannot be generalised. Analyses of changes in means for four elite scullers showed that biomechanical stroke variables did differ significantly between single, double and quad sculls and therefore training and selection should be boat class specific. In elite double sculls, correlations between change in performance and change in bow versus stroke peak force synchronization indicated that it is likely to be beneficial to performance if the stroke peaks with their force earlier and with the handles further to the stern than the bow seat. Switching the seating order in these double sculls resulted in mean boat velocity changing by up to 5.8% of world record time signifying the importance of seat-specific trialling. Extensive differences between elite scullers in the strength and direction of relationships between performance and PowerLine™ variables showed that full analyses of all variables must be conducted individually for each sculler. The importance of seating order in double sculls, and the benefits of the stroke seat peaking before the bow, have implications for crew selection, seat allocation, and technical recommendations. Seat trials for crew sculling boats must be seat-specific and include racing in all seating orders. Further research is necessary to verify and explain the synchronisation requirements of crew sculling boats before more scientific seat allocation can be achieved in these boats. Sculling force profiles from PowerLine™ can be used effectively to measure and improve elite on-water sculling performance.