The Effect of Walking on Depressive and Anxiety Symptoms: Systematic Review and Meta-Analysis

Background: Previous literature lacks summative information on the mental health benefits achieved from different forms of walking. Objective: The aim of this study was to assess the effectiveness of different forms of walking in reducing symptoms of depression and anxiety. Methods: This was a systematic review and meta-analysis of randomized controlled trials (RCTs) assessing the effects of walking on depressive and anxiety symptoms. MEDLINE, CENTRAL, Embase, PsycINFO, AMED, CINAHL, and Web of Science were searched on April 5, 2022. Two authors independently screened the studies and extracted the data. Random-effects meta-analysis was used to synthesize the data. Results were summarized as standardized mean differences (SMDs) with 95% CIs in forest plots. The risk of bias was assessed using the Cochrane Risk of Bias tool. Results: This review included 75 RCTs with 8636 participants; 68 studies reported depressive symptoms, 39 reported anxiety symptoms, and 32 reported both as outcomes. One adolescent study was not included in the meta-analysis. The pooled adult results indicated that walking significantly reduced depressive symptoms (n=44 RCTs; SMD -0.591, 95% CI -0.778 to -0.403; I²=84.8%; τ²=0.3008; P<.001) and anxiety symptoms (n=26 RCTs; SMD -0.446, 95% CI -0.628 to -0.265; I²=81.1%; τ²=0.1530; P<.001) versus inactive controls. Walking significantly reduced depressive or anxiety symptoms in most subgroups (frequency, duration, location, format; all P<.05). Adults who were depressed benefited more for depressive symptoms (n=5 RCTs; SMD -1.863, 95% CI -2.764 to -0.962) than nondepressed adults (n=39 RCTs; SMD -0.442, 95% CI -0.604 to -0.280; P=.002). There was no significant difference between walking and active controls for depressive symptoms (n=17 RCTs; SMD -0.126, 95% CI -0.343 to 0.092; I²=58%; τ²=0.1058; P=.26) or anxiety symptoms (n=14 RCTs; SMD -0.053, 95% CI -0.311 to 0.206; I²=67.7%; τ²=0.1421; P=.69). Conclusions: Various forms of walking can be effective in reducing symptoms of depression and anxiety, with effects comparable to active controls. Walking can be adopted as an evidence-based intervention for reducing depression and anxiety. More evidence on the effect of low-intensity walking is needed. Trial Registration: PROSPERO CRD42021247983.