A meta-analysis of pedometer-based walking interventions and weight loss.
OBJECTIVE
Cross-sectional studies show that individuals who walk more tend to be thinner than those who walk less. This does not mean, however, that the association between higher step counts and lower weight is causal or that encouraging sedentary individuals to increase step counts helps them lose weight.


METHODS
In this meta-analysis, we searched 6 electronic databases and contacted pedometer experts to identify pedometer-based walking studies without a dietary intervention that reported weight change as an outcome. We included randomized controlled trials and prospective cohort studies published after January 1, 1995, in either English or Japanese, with 5 or more adult participants and at least 1 cohort enrolled in a pedometer-based walking intervention lasting at least 4 weeks.


RESULTS
Nine studies met the study inclusion criteria. Cohort sample size ranged from 15 to 106, for a total of 307 participants, 73% of whom were women and 27% of whom were men. The duration of the intervention ranged from 4 weeks to 1 year, with a median duration of 16 weeks. The pooled estimate of mean weight change from baseline using a fixed-effects model and combining data from all 9 cohorts was -1.27 kg (95% confidence interval, -1.85 to -0.70 kg). Longer intervention duration was associated with greater weight change. On average, participants lost 0.05 kg per week during the interventions.


CONCLUSIONS
Pedometer-based walking programs result in a modest amount of weight loss. Longer programs lead to more weight loss than shorter programs.
Richardson
Caroline R
CR
Department of Family Medicine, University of Michigan Medical School, Ann Arbor, MI 48104, USA. caroli@umich.edu
Newton
Tiffany L
TL
Abraham
Jobby J
JJ
Sen
Ananda
A
Jimbo
Masahito
M
Swartz
Ann M
AM
D000328:Adult; D015706:Bibliometrics; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D016206:Databases, Bibliographic / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D008991:Monitoring, Physiologic / Q000295:instrumentation*; D009765:Obesity / Q000628:therapy; D016032:Randomized Controlled Trials as Topic; D016138:Walking / Q000502:physiology / Q000706:statistics & numerical data*; D015431:Weight Loss / Q000502:physiology*