Background: Improved of mood is frequently reported with caffeine intake, probably by improve reaction time, cognitive tasks, attenuate fatigue of exercise and increase arousal
threshold, suggesting that caffeine could contribute to the ability to tolerate prolonged aerobic exercise. However, some studies failed to find a significant association between caffeine, mood and
Methods:To investigate the influence of Caffeine in physical performance, anxiety and physiological responses, seven healthy male subjects (21.86±2.61yrs; 75.81±11.83kg; 1.75±0.05m;
24.60±2.91kg/m2), was submitted to a completion of a 10 km cycling time-trial with analyses of ventilatory responses (ergospirometry). The exercise was performed in two conditions separated by 7
days: Placebo- PLA (Psyllium 5-15 mg with 250 mL of water) and Caffeine – CAF (6 mg/kg with 250 mL of water), 30 minutes before start the exercise in a double-blind protocol. For these conditions, the
subjects answered an anxiety status questionnaire (Idate Trait-State), and temperature and arterial blood pressure was collected before (B), immediately after (IA) and 30 minutes after (30’) finishing
of the exercise. Rated Perceived Exertion (RPE) Scale was used to measure the intensity of exercise during the protocol. The situations were compared by T-Test or two-way ANOVA with post-hoc Duncan
test, with significance p≤0.05. The protocol was approved by Unifesp Ethics Committed (#1.009.434).
Results: We not observed differences related to the ventilatory parameters, blood pressure, RPE and temperature during the 10 Km cycling time trial when compared Placebo vs. Caffeine
conditions and when compared the different time-course. Curiously, we observed increase of anxiety state IA exercise when compared to B, with decrease of this scores at 30’ in PLA condition
(27.83±6.55 (B); 33.33±3.01 (IA); 28.17±5.38 (30’), the CAF condition not show significant differences (33.57±7.21 (B); 33.43±3.95 (IA); 31.29±4.99 (30’).
Conclusions: The Caffeine was not sufficient to influence physical performance in a 10 km cycle time trial test, however, the caffeine maintain anxiety state without change.