Optimizing Training Preparation In University-Level Athletes (18-25 Years): A Systematic Review And Meta-Analysis Of Periodization, Recovery, And Performance Outcomes

Background: The optimization of athletic training in university-level sport science programmes (ages 18-25) requires evidence-based synthesis. Despite a growing body of individual intervention studies on periodization, recovery modalities, and multi-component training, no meta-analysis has systematically quantified the pooled effect sizes across these domains for collegiate athletes. Objectives: To synthesize and meta-analyze the effects of (1) periodization strategies, (2) sleep and nutrition-based recovery protocols, and (3) combined strength-endurance training on physical performance outcomes - including VO₂max, maximal strength (1RM), power output (Wmax), and sport-specific performance indices - in university-level athletes. Methods: A systematic search was conducted in Scopus, PubMed/MEDLINE, SPORTDiscus, and Web of Science (January 2010 - March 2025). Studies were eligible if they: (a) employed randomized or quasi-experimental designs, (b) enrolled healthy university athletes aged 18-25, and (c) reported at least one quantifiable performance outcome. Risk of bias was assessed using the Cochrane RoB 2.0 tool. Random-effects meta-analyses were performed using Hedges' g with 95% confidence intervals. Heterogeneity was quantified via I² statistics. GRADE certainty of evidence was applied to all outcomes. Results: Forty-seven studies (n = 2,314 participants) met inclusion criteria. Periodized training produced large pooled effects on VO₂max (g = 0.88; 95% CI: 0.71-1.05; I² = 42%) and maximal strength (g = 0.93; 95% CI: 0.78-1.08; I² = 38%). Recovery optimization (sleep extension + targeted nutrition) yielded moderate effects on power output (g = 0.61; 95% CI: 0.48-0.74). Combined training programmes demonstrated large effects on sport-specific performance (g = 0.86; 95% CI: 0.70-1.02; I² = 47%). Conclusions: Evidence supports the adoption of block periodization and recovery-integrated programming as the most effective approaches for optimizing multi-dimensional athletic performance in university-level athletes. These findings provide a robust evidence base for national physical education curricula reform in higher-education sport science programmes.