(P29-004-25) Coffee Roast Level and Anaerobic Exercise

Objectives: Coffee has been linked to improvements in aerobic exercise performance. Roasting coffee affects its chemistry, both destroying and creating compounds that impact the flavor of the coffee and its composition. This pilot study investigated the impact of the level of roasting coffee on composition and anaerobic power and strength output in human test subjects.

Methods: A single batch of green coffee was quartered and roasted to light, medium, and dark with the last quarter remaining green before analytical testing for caffeine, chlorogenic acid (3CQA), and total phenolic content. Ten subjects were tested for baseline performance using a digital hand dynamometer for grip strength, a force plate for countermovement jump height (CMJH), and an isolateral leg press for power output during the movement. The subjects then repeated the tests five times on five different days, 30 minutes after consuming: green coffee; light; medium; and dark roast coffee; and a no coffee control. A one-way analysis of variance (ANOVA) compared each treatment to the baseline value.

Results: Grip strength results were as follows: baseline 42.81 ± 12.24 kg; control 43.06 ± 11.14; green coffee 43.39 ± 10.61; light 43.13 ± 10.46; medium 43.11 ± 10.32; and dark roast 44.25 ± 12.00 kg. CMJH results were: baseline 39.92 ± 61.31; control 22.33 ± 8.71; green coffee 18.60 ± 8.51; light 21.84 ± 10.20; medium 21.98 ± 9.85; and dark roast 19.20 ± 7.80 cm. Leg press results were inconclusive due to system crash and equipment failure. Results for caffeine content were: green coffee 68.54 ± 0.15; light 91.58 ± 0.26; medium 87.96 ± 0.40, and dark roast 78.90 ± 0.27mg/kg. Results for total phenolic content were: green coffee 9.05 ± 0.35: light 14.20 ± 0.78; medium 12.22 ± 0.41; and dark roast 9.98 ± 0.08 mM. Results for 3 CQA were: green coffee 114.70 ± 1.40; light 113.65 ± 0.05; medium 81.18 ± 0.65; and dark roast 19.31 ± 0.05 mg/L.

Conclusions: Light roast coffee remained significantly high in caffeine, 3 CQA, and total phenolic compounds even though the study did not yield statistically significant differences in anaerobic performance among coffee treatments. Future studies should include more participants from the same population and additional performance measurements to effectively determine if coffee roast level impacts anaerobic performance.

Funding Sources: North Carolina State University, Elon University