The One Giant Leap Commercial Wireless Power Meter Can Be Used for Sprint Kayaking with The Appropriate Calibration

Joshua A GorehamMichel Ladouceur^*

• School of Health and Human Performance, Faculty of Health, Dalhousie University, Halifax, Canada

For full guidelines please refer to Author Guidelines Purpose: Two experiments were used to determine the construct and concurrent validity of a commercial kayak paddle shaft power meter (OGL) for measuring force and power output in female sprint kayakers. Methods and Results: Construct validity: Seven female participants used the same OGL paddle to complete 30 second trials at different stroke rates (60, 80, 100, maximum strokes per minute) while a global positioning system measured kayak velocity. Regression analysis provided a large coefficient of determination (R2≥0.83) between mean power and mean velocity (f(x) =6.892x3). Concurrent validity: Two known weight combinations were used to calibrate the paddle (wide range: 51.5-394.9 N; narrow range: 100.6-247.7 N), whereas both left and right sides of the shaft were statically loaded eight separate times with known weights (51.5 N to 394.9 N at 49.1 N intervals) to test its concurrent validity. The right side of the shaft had proportional bias (p<0.001) and the left side of the shaft had fixed bias (65.7±21.1 N, p=0.017) when calibrated with a narrow range. Neither shaft side had proportional bias, but both shaft sides had small, fixed biases (left: 18.3±7.4 N, p=0.043; right: 9.3±3.0 N, p=0.018) when calibrated with a wide range. Conclusion: the study establishes that even though the OGL reports power values that appear to have construct validity up to 4.6m•s -1 , calibration with a range of weights that encompasses the projected applied forces is needed to improve the accuracy of the force measurement, and thus the power calculation, by the OGL.