2.3. Statistical Analysis
RPE
Data normality was confirmed using the Shapiro–Wilk test. Therefore, the results were presented as mean ± standard deviation (SD). RPE and Stroop test performance (response time and accuracy) were assessed using a 2-way repeated measures analysis of variance using the Geisser–Greenhouse epsilon correction for violations of the sphericity assumption. The independent variables used in the analysis were: condition (placebo vs. caffeine); and time (from SSG1 to SSG5 in the RPE assessment and pre- vs. post-SSG protocol on the Stroop test analysis). Post hoc analysis using Tukey’s multiple comparisons test was performed where any significant interaction and main effects were found. A 