Exploratory Systematic Review and Meta-Analysis of Panax Genus Plant Ingestion Evaluation in Exercise Endurance

Background: Many studies that use food containing Panax genus plants (PGPs) have been conducted but most of them have not mentioned the effective compounds ginsenosides and their composition. Therefore, we conducted a systematic review and meta-analysis of time to exhaustion as an index of exercise endurance with ingestion of PGPs or ginsenosides to reveal their effects. Methods: We performed a systematic review with a comprehensive and structured literature search using seven literature databases, four clinical trial databases, and three general web search engines during 15–22 March 2021. A random-effects model was applied to calculate the standardized mean difference (SMD) and 95% confidence interval (CI) as the difference between the mean in the treatment and placebo groups. We evaluated the risk of bias of individual studies along with the risk of bias tool in the Cochrane handbook. This study was funded by Maruzen Pharmaceuticals Co., Ltd. (Hiroshima, Japan). The protocol for this study was registered with the UMIN-CTR (No. UMIN000043341). Results: Five studies met the inclusion criteria. The number of total participants was 90, with 59 in the ingestion-PGPs group and 64 in the control group, because three studies were crossover-design trials. We found that ingestion of PGPs or ginsenosides significantly improved exercise endurance (SMD [95% CI]: 0.58 [0.22–0.95], I² = 0%). It was suggested that ginsenoside Rg₁ (Rg₁) and PGPs extract containing Rg₁ were significantly effective in improving exercise endurance (SMD [95% CI]: 0.70 [0.14–1.27], I² = 30%) by additional analysis. Conclusions: This systematic review suggests that the ingestion of PGPs or ginsenosides, especially Rg₁, is effective in improving exercise endurance in healthy adults. However, further high-quality randomized controlled trials are required because imprecision and publication bias cannot be ignored in this systematic review.