2134/22645 Paul Sindall Paul Sindall John P. Lenton John P. Lenton Katie Whytock Katie Whytock Keith Tolfrey Keith Tolfrey Michelle L. Oyster Michelle L. Oyster Rory A. Cooper Rory A. Cooper Vicky Goosey-Tolfrey Vicky Goosey-Tolfrey Criterion validity and accuracy of global positioning satellite and data logging devices for wheelchair tennis court movement Loughborough University 2016 Aerobic fitness Spinal cord injuries Disability sport Tennis Global positioning system Wheelchairs Data logging Distance Speed Medical and Health Sciences not elsewhere classified 2016-10-03 10:26:28 Journal contribution https://repository.lboro.ac.uk/articles/journal_contribution/Criterion_validity_and_accuracy_of_global_positioning_satellite_and_data_logging_devices_for_wheelchair_tennis_court_movement/9628235 PURPOSE. To compare the criterion validity and accuracy of a 1 Hz non-differential global positioning system (GPS) and data logger device (DL) for the measurement of wheelchair tennis court movement variables. METHODS. Initial validation of the DL device was performed. GPS and DL were fitted to the wheelchair and used to record distance (m) and speed (m/second) during (a) tennis field (b) linear track, and (c) match-play test scenarios. Fifteen participants were monitored at the Wheelchair British Tennis Open. RESULTS. Data logging validation showed underestimations for distance in right (DLR) and left (DLL) logging devices at speeds >2.5 m/second. In tennis-field tests, GPS underestimated distance in five drills. DLL was lower than both (a) criterion and (b) DLR in drills moving forward. Reversing drill direction showed that DLR was lower than (a) criterion and (b) DLL. GPS values for distance and average speed for match play were significantly lower than equivalent values obtained by DL (distance: 2816 (844) vs. 3952 (1109) m, P = 0.0001; average speed: 0.7 (0.2) vs. 1.0 (0.2) m/second, P = 0.0001). Higher peak speeds were observed in DL (3.4 (0.4) vs. 3.1 (0.5) m/second, P = 0.004) during tennis match play. CONCLUSIONS. Sampling frequencies of 1 Hz are too low to accurately measure distance and speed during wheelchair tennis. GPS units with a higher sampling rate should be advocated in further studies. Modifications to existing DL devices may be required to increase measurement precision. Further research into the validity of movement devices during match play will further inform the demands and movement patterns associated with wheelchair tennis.