Effect of Acute Coffeeberry Extract on Self-Reported Mental Energy and Physical Performance Following a Fatiguing Cognitive Task: a Randomized, Double-Blind Controlled Trial

Objectives To assess the acute effects of two doses of coffeeberry (CB®) extract use on (i) mental energy and fatigue-related feelings (primary outcomes) and (ii) cycling performance (exploratory outcome). Methods Twenty-eight adults completed a randomized, double-blind, placebo-controlled, cross-over experiment. Treatments were a base beverage supplemented with a CB® extract at doses of 100 mg (CB®100) and 300 mg (CB®300). The base beverage alone was the placebo (PL) and the base beverage with 75 mg caffeine (CAFF) was the positive control. Participants consumed one of the four beverages during four separate visits. Before (BL) and one-hour post-treatment (Post 1), cognitive tests and scales assessing the mood states of alertness, energy and fatigue were completed, taking 55-min. Two-hours post-treatment, a 20-min-high intensity interval cycling protocol was performed followed by a 3-min all-out time trial. Treatment effects on primary outcomes were tested using repeated measures ANOVAs. Cycling performance outcomes were tested using dependent t-tests. Results There was a significant Beverage x Time interaction for alertness ( p = 0.008), mental energy ( p = 0.009), and mental fatigue ( p = 0.008). Post-hoc analysis showed significant improvements from BL to Post 1 in the CAFF condition for alertness ( p = 0.002); and mental energy ( p = 0.006). Conclusions Beverages containing 100 mg or 300 mg CB® extract consumed one-hour before a cognitive test and two-hours before a high intensity exercise bout does not influence feelings of alertness, mental energy and fatigue or cycling performance. A 75 mg dose of caffeine transiently improves feelings of alertness and mental energy. Trial Registration The trial is registered at the US National Institutes of Health (ClinicalTrials.gov) #NCT03870126. Presented at the American Society of Nutrition, 2021.