Statistical analysis
fatigue
REGRESSION
For each trial, mean values for time to completion (hr:min:sec), peak and average power output (W), and VAS responses were computed for the 20 km TT test. Mean values for time to fatigue (hr:min:sec) and VAS responses were computed for the HIEC test. Differences between trials were assessed with a paired samples T-test. Mean values were computed for the OMNI perceived exertion measures in the 20 km TT and analyzed with a two-way repeated measures ANOVA. Pearson correlation coefficients were computed to assess the relationship individually for both supplement and placebo trials with regard to 20 km TT average power, 20 km TT peak power, 20 km TT time to completion, HIEC time to fatigue, and VO2 max. A simple linear regression was performed for significant correlations. A chi-square test of independence was performed to examine the relationship between the order of treatment (supplement first or placebo first) and whether there was improvement between the two trials (yes or no) for the 20 km TT time to completion, 20 km TT average power, 20 km TT peak power, and HIEC time to fatigue. The same statistical approach was used to examine the relationship between the age range (30–39, 40–49, 50–59) and the same test variables. Data were analyzed using SPSS (Version 28.0.1.0) with a significance set at 