Do Pedometers Work?Tuesday, August 12, 2008
Yesterday’s post, as expected, provoked several e-mail responses (not sure, why folks are shy about posting comments directly on the site).
One reader asked if there was any evidence that asking patients to wear pedometers actually works.
The simple answer is: Yes, it does!
This answer is based on a meta-analysis of pedometer-based walking interventions and weight loss by Caroline Richardson and colleagues from the University of Michigan, published earlier this year in the Annals of Family Medicine.
For this meta-analysis, Richardson and colleagues 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. Nine studies met the 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.
So, evidently, pedometer-based walking programs do result in a modest amount of weight loss, whereby longer programs lead to more weight loss than shorter programs.
Two important messages here:
1. By themselves, pedometers are hardly the greatest obesity intervention (actually, even more intense exercise, despite its many health benefits, is by itself highly over-rated as a weight-loss strategy).
2. As with all obesity management strategies, any intervention should be aimed for life – using a pedometer for a few weeks or even months is probably useless, as the weight would simply come back the minute your patient stops using it.
In case anyone is wondering why bother if the weight loss is so modest: the point is not the weight loss – the point is that any increase in physical activity, if sustained, is more likely to prevent weight regain, than any regimen that is based on caloric restriction alone. A pedometer is simply the simplest tool to objectively self-monitor physical activity (sure, accelerometers are even better, but cost 10-100 times as much).
Tip: ask you patient to invest in a decent device – the cheaper, the more prone to inaccuracy and frustration – a good device will cost around $20-30 – money well spent!