Objective To assess the health benefits of outdoor walking groups.

Design Systematic review and meta-analysis of walking group interventions examining differences in commonly used physiological, psychological and well-being outcomes between baseline and intervention end.

Data sources Seven electronic databases, clinical trial registers, grey literature and reference lists in English language up to November 2013.

Eligibility criteria Adults, group walking outdoors with outcomes directly attributable to the walking intervention.

Results Forty-two studies were identified involving 1843 participants. There is evidence that walking groups have wide-ranging health benefits. Meta-analysis showed statistically significant reductions in mean difference for systolic blood pressure −3.72 mm Hg (−5.28 to −2.17) and diastolic blood pressure −3.14 mm Hg (−4.15 to −2.13); resting heart rate −2.88 bpm (−4.13 to −1.64); body fat −1.31% (−2.10 to −0.52), body mass index −0.71 kg/m² (−1.19 to −0.23), total cholesterol −0.11 mmol/L (−0.22 to −0.01) and statistically significant mean increases in VO_2max of 2.66 mL/kg/min (1.67–3.65), the SF-36 (physical functioning) score 6.02 (0.51 to 11.53) and a 6 min walk time of 79.6 m (53.37–105.84). A standardised mean difference showed a reduction in depression scores with an effect size of −0.67 (−0.97 to −0.38). The evidence was less clear for other outcomes such as waist circumference fasting glucose, SF-36 (mental health) and serum lipids such as high-density lipids. There were no notable adverse side effects reported in any of the studies.

Conclusions Walking groups are effective and safe with good adherence and wide-ranging health benefits. They could be a promising intervention as an adjunct to other healthcare or as a proactive health-promoting activity.