Short-Term Effects of Using Pedometers to Increase Daily Physical Activity in Smokers: A Randomized Trial

Abstract

In adults it is recommended that the minimum of 10,000 steps/day should be performed in order to consider an individual as active. The pedometer, a small device that counts steps, has been used to monitor and/or motivate physical activity in various populations. To investigate the short-term effects of a protocol using a pedometer or an informative booklet to increase daily physical activity in apparently healthy smokers who reached or did not reach the minimum public health recommendation of 10,000 steps/day. Subjects were randomly assigned to 2 groups: group pedometer (GP, n = 23), who wore a pedometer every day during 1 month, aiming to achieve 10,000 steps/day; and group booklet (GB, n = 17), who received a booklet with encouragement to walk as much as possible in everyday life. Each group was subdivided according to their baseline daily physical activity level: active (subjects who achieved 10,000 steps/day), and inactive (those who did not achieve this minimum). Only the physically inactive GP increased significantly its daily physical activity (pre vs post 7,670 [6,159-9,402] steps/day vs 10,310 [9,483-11,110] steps/day, P < .001), with a concomitant increase in the 6-min walking test (6MWT) distance (mean and interquartile range 540 m [501-586 m] vs 566 m [525-604 m], P = .03). In GP, Δ post-pre steps/day correlated significantly with baseline number of steps/day (r = -0.63, P = .01), but not with 6MWT. In the inactive subjects (summing GP and GB), there were significant correlations between steps/day and cigarettes/day, pack-years, and Fagerström questionnaire (r = -0.55, -0.40, and -0.59, P ≤ .05 for all). Furthermore, improvement in steps/day in the inactive subjects of GP was correlated with baseline cigarettes smoked per day, pack-years, and Fagerström questionnaire (r = 0.51, 0.65 and 0.53, P ≤ .05 for all). Physically inactive smokers improve their daily physical activity level by using a simple tool (pedometer), and larger improvement occurs in subjects with the lowest levels of physical activity.