C-26 Free Communication/Poster - Objective Measures: Accelerometry and Pedometry: JUNE 3, 2010 7:30 AM - 12:30 PM: ROOM: Hall C
Pedometers could provide great insights into walking habits, if they are found to be accurate for people of all weight categories.
PURPOSE: To determine if the New Lifestyles NL-2000 (NL) and the Digi-Walker SW-200 (DW) yield similar daily step counts compared to the StepWatch 3 (SW-3) in a free-living environment and to determine if pedometer error is influenced by adiposity and speed of walking. The SW-3 served as the criterion, due to its extreme accuracy across a range of speeds and BMI categories. Slow walking was defined as <80 steps per minute.
METHODS: Fifty-six adults (32.7 ± 14.5 y) wore the devices for seven days. There were 20 normal weight, 18 overweight, and 18 obese participants. A two-way repeated measures ANOVA was performed to determine if BMI and device were related to number of steps counted per day. Stepwise linear regressions were performed to determine what variables contribute to NL and DW error.
RESULTS: Both the NL and DW recorded fewer steps than the SW-3 (P<0.001). In the normal weight and overweight groups, error was similar for the DW and NL. In the obese group, the DW underestimated steps more than the NL (P<0.01). DW error was positively related to BMI and percentage of steps taken at a slow pace, while NL error was linearly related to percentage of slow steps. A surprising finding was the volume of slow walking steps accumulated by healthy, community-dwelling adults.
CONCLUSIONS: The NL is more accurate for obese individuals, and neither pedometer is accurate for people who accumulate steps at a slow walking speed.