The effects of complex training on performance variables in basketball players: a systematic review and meta-analysis

Introduction: Basketball requires explosive power, agility and change of direction (CoD) ability. Although often used interchangeably with agility, CoD is distinct: it involves rapid directional changes in response to a pre-planned stimulus, while agility also requires perceptual cognitive responses to unpredictable cues. In this review agility is considered under CoD, emphasizing the physical component that can be directly trained. Improving CoD and power is essential for optimal basketball performance. Complex training (CT), which combines strength and plyometric exercises, has emerged as a promising method. However, its specific effects on basketball player's physical performance variables remain unclear, warranting a focused systematic review and meta-analysis. Methods: A structured search strategy was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA 2020) guidelines and the PICOS framework. PubMed, Web of Science, and Scopus databases were searched to identify appropriate Randomized Clinical Trials (RCTs) relating to CT in basketball players, up to May 2025. Standardised mean differences (SMDs), with 95% confidence intervals (CI), were calculated using a random-effects model. Heterogeneity (I2), sensitivity analysis, and publication bias were assessed using standard methods. Seven RCTs were included in the meta-analysis. Results: Analysing within-group effects following CT demonstrated significant improvements in CoD speed (SMDs: 1.11; 95%CI: 0.56 to 1.66; p < 0.001, I2:53), and vertical jump performance (SMDs: −1.44; 95%CI: −2.16 to −0.72; p < 0.001, I2:91). However, between-group comparisons (CT vs. active controls) revealed significant improvements only in CoD speed (SMDs: −1.04; 95%CI: −1.61 to −0.47; p < 0.001, I2:57) and vertical jump performance (SMDs: 1.01; 95%CI: 0.46 to 1.56; p < 0.001, I2:86). Funnel plot analysis indicated moderate asymmetry for CoD speed and clear asymmetry with outliers for vertical jump performance. Conclusion: Our findings demonstrate that CT significantly enhances jump performance and CoD speed in basketball players. This study highlights the efficacy of CT in significantly improving CoD speed and jump performance in basketball players. These findings support its inclusion in athletic conditioning programs and offer valuable insights for coaches and practitioners aiming to optimize sport-specific performance through targeted training interventions. Systematic Review Registration: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251057718. PROSPERO (CRD420251057718).