Paul W Macdermid1, Josh Wharton2, Carina Schill2, Philip W Fink2. 1. Massey University, College of Health, School of Sport & Exercise, Private Bag 11-222, Palmerston North 4474, New Zealand. Electronic address: p.w.macdermid@massey.ac.nz. 2. Massey University, College of Health, School of Sport & Exercise, Private Bag 11-222, Palmerston North 4474, New Zealand.
Abstract
PURPOSE: The purpose of this study was to compare impact loading, kinematic and physiological responses to three different immersion depths (mid-shin, mid-thigh, and xiphoid process) while running at the same speed on a water based treadmill. METHODS: Participants (N=8) ran on a water treadmill at three depths for 3min. Tri-axial accelerometers were used to identify running dynamics plus measures associated with impact loading rates, while heart rate data were logged to indicate physiological demand. RESULTS: Participants had greater peak impact accelerations (p<0.01), greater impact loading rates (p<0.0001), greater stride frequency (p<0.05), shorter stride length (p<0.01), and greater rate of acceleration development at toe-off (p<0.0001) for the mid-shin and mid-thigh compared to running immersed to the xiphoid process. Physiological effort determined by heart rate was also significantly less (p<0.0001) when running immersed to the xiphoid process. CONCLUSION: Water immersed treadmill running above the waistline alters kinematics of gait, reduces variables associated with impact, while decreasing physiological demand compared to depths below the waistline.
PURPOSE: The purpose of this study was to compare impact loading, kinematic and physiological responses to three different immersion depths (mid-shin, mid-thigh, and xiphoid process) while running at the same speed on a water based treadmill. METHODS:Participants (N=8) ran on a water treadmill at three depths for 3min. Tri-axial accelerometers were used to identify running dynamics plus measures associated with impact loading rates, while heart rate data were logged to indicate physiological demand. RESULTS:Participants had greater peak impact accelerations (p<0.01), greater impact loading rates (p<0.0001), greater stride frequency (p<0.05), shorter stride length (p<0.01), and greater rate of acceleration development at toe-off (p<0.0001) for the mid-shin and mid-thigh compared to running immersed to the xiphoid process. Physiological effort determined by heart rate was also significantly less (p<0.0001) when running immersed to the xiphoid process. CONCLUSION:Water immersed treadmill running above the waistline alters kinematics of gait, reduces variables associated with impact, while decreasing physiological demand compared to depths below the waistline.
Authors: Billy C L So; Manny M Y Kwok; Veron C Y Fung; Ally H Y Kwok; Crystal W C Lau; Alison L Y Tse; Mini S Y Wong; John A Mercer Journal: J Hum Kinet Date: 2022-04-26 Impact factor: 2.923