OBJECTIVE: To conduct a systematic review and meta-analysis of randomised control trials that examined the effect of walking on risk factors for cardiovascular disease.
METHODS: Four electronic databases and reference lists were searched (Jan 1971-June 2012). Two authors identified randomised control trials of interventions = 4 weeks in duration that included at least one group with walking as the only treatment and a no-exercise comparator group. Participants were inactive at baseline. Pooled results were reported as weighted mean treatment effects and 95% confidence intervals using a random effects model.
RESULTS: 32 articles reported the effects of walking interventions on cardiovascular disease risk factors. Walking increased aerobic capacity (3.04 mL/kg/min, 95% CI 2.48 to 3.60) and reduced systolic (-3.58 mm Hg, 95% CI -5.19 to -1.97) and diastolic (-1.54 mm Hg, 95% CI -2.83 to -0.26) blood pressure, waist circumference (-1.51 cm, 95% CI -2.34 to -0.68), weight (-1.37 kg, 95% CI -1.75 to -1.00), percentage body fat (-1.22%, 95% CI -1.70 to -0.73) and body mass index (-0.53 kg/m(2), 95% CI -0.72 to -0.35) but failed to alter blood lipids.
CONCLUSIONS: Walking interventions improve many risk factors for cardiovascular disease. This underscores the central role of walking in physical activity for health promotion.
Unfortunately, all included trials are very small and I can`t tell whether the results reported are real or just due to small study effects (the latter is very probable). So, yes, the topic is really relevant, but, no, there is nothing to be reported to clinical colleagues, except that a large trial is urgently needed.
This systematic review shows that walking interventions improve risk factors (increase aerobic capacity, reduce systolic and diastolic blood pressure, reduce waist circumference, reduce weight, reduce percentage body fat and reduce BMI) for cardiovascular disease. However, walking interventions have no effect on blood lipids. The meta-analysis is well designed and carefully executed. The authors pooled the results of a sufficient number of studies (32 RCTs).
This is a meta-analysis of studies looking at the cardiac effects of a walking regimen. Shocking news! Walking is good for the heart. This paper has all the pitfalls of a meta-analysis -- large number of studies eliminated because of they couldn`t be analyzed and no clear statement of what type of walking, duration, intensity, or gradient to recommend to patients. The meta-analysis was also limited in examining other markers of heart disease such as inflammatory markers.
It is good to know that something I recommend very strongly to my patients has some scientific heft to it.
Walking is good for you. It's nice to have a meta-analysis for those times when you want to have some clinical trials evidence, but probably does not change practice for most practitioners.
The results of this meta-analysis provide us with a powerful tool to educate our colleagues. We are the care providers and we need to be convinced. That is the only way to give exercise the true relevance it should have in the primary prevention of cardiovascular diseases and of many other conditions.