RESUMO
The purpose of the present study was to evaluate the ergogenic effect of caffeine ingestion on mood state, simple reaction time, and muscle power during the Wingate test recorded in the morning on elite Judoists. Twelve elite judoists [age: 21.08 +/- 1.16 years, body mass: 83.75 +/- 20.2 kg, height: 1.76 +/- 6.57 m] participated in this study. Mood states, simple reaction time, and muscle power during the Wingate test were measured during two test sessions at 07:00 h and after placebo or caffeine ingestion [i.e. 5 mg/kg]. Plasma concentrations of caffeine were measured before [T0] and 1-h after caffeine' ingestion [T1] and after the Wingate test [T3]. Our results revealed an increase of the anxiety and the vigor [P<0.01], a reduction of the simple reaction time [P<0.001] and an improvement of the peak and mean powers during the Wingate test. However, the fatigue index during this test was unaffected by the caffeine ingestion. In addition, plasma concentration of caffeine was significantly higher at T1 in comparison with T0. In conclusion, the results of this study suggest that morning caffeine ingestion has ergogenic properties with the potential to benefit performance, increase anxiety and vigor, and decrease the simple reaction time
RESUMO
The purpose of this study was to examine the effects of Ramadan fasting on circulating levels of interleukin-12 [IL-12] after a brief maximal exercise. Nine subjects performed a Wingate test on three different occasions: [i] the first week of Ramadan [1WR], [ii] the fourth week of Ramadan [4WR], and [iii] three weeks after Ramadan [AR]. Blood samples were taken before, immediately and 60 min after the exercise. Plasma concentrations of IL-12 were measured using enzyme-linked immunosorbent assay. Variance analysis revealed no significant effect of Ramadan on Ppeak and Pmean during the three testing periods. Considering the effect of Ramadan on plasma concentrations of IL-12, analysis of the variance revealed a significant Ramadan effect [F[2, 16]=66.27 ; P<0.001] as well as a significant time effect [F[2, 16]=120.66; P<0.001]. However, no significant [Ramadan time] of test interaction [F[4, 32]=2.40; P>0.05]. For all measures, IL-12 levels were lower during 1WR and 4WR in comparison with AR [P<0.05]. Considering the exercise effects, IL-12 levels measured immediately after the exercise were significantly higher than those measured before and at 60 minutes after the exercise [P<0.001]. These results suggest that an acute intense exercise-induced IL-12 response is modified by daytime fasting and modifications in sleep schedule during Ramadan