Background and objective: The role of leisure-time physical activity in sciatica is uncertain. This study aimed to assess the association of leisure-time physical activity with lumbar radicular pain and sciatica. Databases and data treatment: Literature searches were conducted in PubMed, Embase, Web of Science, Scopus, Google Scholar and ResearchGate databases from 1964 through August 2015. A random-effects meta-analysis was performed, and heterogeneity and small-study bias were assessed. Results: Ten cohort (N = 82,024 participants), four case-control (N = 9350) and four cross-sectional (N = 10,046) studies qualified for meta-analysis. In comparison with no regular physical activity, high level of physical activity (≥4 times/week) was inversely associated with new onset of lumbar radicular pain or sciatica in a meta-analysis of prospective cohort studies [risk ratio (RR) = 0.88, 95% CI 0.78-0.99, I2 = 0%, 7 studies, N = 78,065]. The association for moderate level of physical activity (1-3 times/week) was weaker (RR = 0.93, CI 0.82-1.05, I2 = 0%, 6 studies, N = 69,049), and there was no association with physical activity for at least once/week (RR = 0.99, CI 0.86-1.13, 9 studies, N = 73,008). In contrast, a meta-analysis of cross-sectional studies showed a higher prevalence of lumbar radicular pain or sciatica in participants who exercised at least once/week [prevalence ratio (PR) = 1.29, CI 1.09-1.53, I2 = 0%, 4 studies, N = 10,046], or 1-3 times/week (PR = 1.34, CI 1.02-1.77, I2 = 0%, N = 7631) than among inactive participants. There was no evidence of small-study bias. Conclusions: This meta-analysis suggests that moderate to high level of leisure physical activity may have a moderate protective effect against development of lumbar radicular pain. However, a large reduction in risk (>30%) seems unlikely.