Ostojic SM, Stojanovic, MD, Djordjevic B, Jourkesh M, Vasiljevic N. The effects of a 4-week coffee berry supplementation on antioxidant status, endurance, and anaerobic performance in college athletes. Res Sports Med. 2008;16: 1-14.
Physical exercise increases oxygen consumption, which, in turn, increases the production of reactive oxygen species and free radicals. The increase in antioxidant capacity known to occur with endurance training may not be sufficient to neutralize this increase in free radical production. Thus, nutritional supplements rich in bioavailable antioxidants have become particularly popular in physically active persons over the past decade. However, the effects of antioxidant supplements on antioxidant status, cellular structure, and performance are not clearly understood. In physically active persons, antioxidant supplementation has been shown to have beneficial effects on performance and recovery (e.g., increased energy levels and a decreased risk of muscle injury) in some studies but to cause decreases in training efficiency and in cellular antioxidant adaptation in other studies. Therefore, the benefit of antioxidant supplementation in athletes is controversial. The objective of this study was to evaluate changes in total antioxidant capacity (TAC) and in aerobic and anaerobic performance in college athletes after supplementation with coffee (Coffea spp.) berry (CB).
Twenty healthy college athletes (14 men and 6 women) were
recruited for this study, which was conducted at the University of Belgrade,
Serbia. The subjects were randomly assigned to receive CB capsules (400 mg each
twice daily) or placebo capsules (cellulose) for 28 days. Both the CB and
placebo capsules were manufactured by Futureceuticals (
No significant differences in baseline measures were observed between the CB and placebo groups. The mean (± SD) TAC was significantly greater in the CB group than in the placebo group after supplementation and was significantly greater after supplementation (1.66 ± 0.16 mmol/L) than at baseline (1.54 ± 0.13 mmol/L) in the CB group. The mean (± SD) HRR index was also significantly greater in the CB group than in the placebo group after supplementation and was significantly greater after supplementation (38 ± 4 beats/min) than at baseline (32 ± 9 beats/min) in the CB group. Lactrec decreased significantly in the CB group after supplementation (from 7.6 ± 4.2 to 5.5 ± 2.6 mmol/L) and was significantly lower in the CB group than in the placebo group after supplementation. Glucose, total cholesterol, high-density and low-density lipoproteins, triglycerides, HRmax, Lactmax, average anaerobic power, maximal oxygen uptake, and the index of anaerobic fatigue did not change significantly from baseline and were not significantly different between the CB and placebo groups after supplementation. None of the subjects reported any adverse side effects.
The results indicate that CB supplementation slightly but significantly increased TAC but had only "minimal effects" on the recovery parameters measured after exercise in college athletes. To the authors' knowledge, this study was the first to directly analyze the effects of CB supplementation on antioxidant status and exercise performance in athletes. Because no data are available in peer-reviewed journals to corroborate these data, the authors recommend that additional research be conducted to determine the possible underlying mechanisms for the observed effects. Possible variables to be studied include the changes in dosage and duration and the nature and intensity of training on anaerobic performance and endurance.
—Brenda Milot, ELS