RAT: Reactive agility test; PAT: Pre-planned agility test; RT: Reaction test; B-Outliers: Before outliers were excluded; Full: Model fitted using data after influential studies excluded; Reduced: Model fitted after significant different baseline data was excluded; df: Degree of freedom; REML: Restricted maximum-likelihood; ML: maximum-likelihood; Change: Calculating effect size using change score; Level 2: Heterogeneity within the study; Level 3: Heterogeneity between the study