Fig. 5
Meta-analysis of V̇O2max. A random effects model was used to determine the effect of post-exercise heat exposure (heat acclimation) on V̇O2max in millilitres per kilogram body weight per minute (mL/kg/min). The meanΔ values in the control and treatment groups represent the post-intervention minus pre-intervention change scores. The mean difference values represent the difference in the change scores between the treatment and control groups, i.e. (PostTreatment—PreTreatment)—(PostControl—PreControl). The overall risk of bias for this outcome in each study is rated as high ( ×), low (✓), or some concerns (!). The forest plot bubbles represent the standardised mean difference (SMD; Hedges’ g) for each study. The size of the bubbles represents the weights of each study in the inverse variance model. Error bars represent the 95% confidence interval (CI). The 95% prediction interval is shown in orange. N = sample size; SE = standard error; Z = z-test statistic and the corresponding p-value; Q = Cochrane’s Q; I2 = percentage variability in effect sizes across studies; Tau2 and Tau are measures of the dispersion of true effect sizes between studies