Date of Award
Thesis and Dissertation
Master of Science (MS)
School of Kinesiology and Recreation
Kelly R. Laurson
The purpose of this study was to examine the step count validity of the pendulum-based Yamax Digiwalker SW-701 pedometer (YX), piezoelectric Omron HJ-720-T pedometer (OP), uni-axial Polar Active accelerometer (PAC), and micro electro-mechanical system Actigraph gt3x accelerometer (AG) during controlled and free-living conditions. A convenience sample of college-aged students participated in Study 1 (treadmill walking, n = 43; 21 females) and Study 2 (free-living, n = 37; 18 females). During study 1, subjects walked on a treadmill at five speeds for 3-minutes per stage wearing all four devices while a researcher manually counted steps which provided a criterion measure. During study 2, subjects wore the devices for 3-days while performing their normal activities. The YX was utilized as the comparative monitor. Results: In Study 1, the OP was within 1.1% of manually counted steps during all speeds while the PAC was not accurate during any speed ranging in error from 6.7% to 16%. The YX and AG were inaccurate at slow speeds, but became accurate as speed increased. In Study 2, the OP mean percent error ranged from -1.0 to -3.3% daily compared to the YX. The AG step counts were also accurate compared to the YX (mean percent error between +2.2 and -2.5% daily). The PAC overestimated steps by 44.0% (5,265 steps) per day. This overestimation was observed for each of the three days when observed individually with mean error between 40.8% - 50.0% per day. Conclusion: In our sample of apparently healthy individuals, the OP and AG provided reliable stepping information. Caution should be used if selecting the PAC if stepping information is targeted. Future studies validating the step count validity of these monitors in additional populations is warranted.
Lee, Joey, "Validity of Four Activity Monitors during Controlled and Free-Living Conditions" (2013). Theses and Dissertations. 165.