Evidence for behavioural effects of caffeine is well documented in the literature. It is associated with increased subjective alertness, improved reaction time and enhanced encoding of new information. These effects are most prominent in low arousal situations. However, there is an ongoing debate as to whether such changes are in fact improvements or merely a reversal of the negative effects of...

PURPOSE This study investigated the effects of a low and moderate caffeine dose on exogenous CHO oxidation and endurance-exercise performance. METHODS Nine trained and familiarized male cyclists (mean +/- SD: 29.4 +/- 4.5 yr, 81.3 +/- 10.8 kg body weight [BW], 183.8 +/- 8.2 cm, V O2peak = 61.7 +/- 4.8 mL.kg.min) undertook three trials, with training and high CHO diet being controlled. One hou...

The present study was conducted to investigate whether green tea may improve weight maintenance by preventing or limiting weight regain after weight loss of 5 to 10 % in overweight and moderately obese subjects. The study had a randomised, parallel, placebo-controlled design. A total of 104 overweight and moderately obese male and female subjects (age 18-60 years; BMI 25-35 kg/m(2)) participate...

background evidence indicates that insulin resistance results in poor sustained viral response (svr) in patients with chronic hepatitis c (chc). metformin is an oral hypoglycemic agent which improves insulin resistance. methods we sought to determine if the addition of metformin to the treatment regimen could improve svr in treatment-naive chc patients in a randomized, double-blind, placebo-con...

Despite the widespread use of caffeine as a central nervous stimulant, the central pharmacodynamic properties of the drug have not yet been conclusively evaluated in humans. The present study was undertaken to assess the acute effects of caffeine on measures of topographical quantitative electroencephalogram (EEG) in normal subjects. Ten healthy male volunteers (mean age +/- SD 25 +/- 4 years) ...

Caffeine increases time to fatigue [limit of endurance (T(lim))] during submaximal isometric contractions without altering whole muscle activation or neuromuscular junction transmission. We used 10 male volunteers in a randomized, double-blind, repeated-measures experiment to examine single motor unit firing rates during intermittent submaximal contractions and to determine whether administerin...

INTRODUCTION Preclinical studies have shown that the endogenous nucleoside adenosine prevents excessive tissue injury during systemic inflammation. We aimed to study whether endogenous adenosine also limits tissue injury in a human in vivo model of systemic inflammation. In addition, we studied whether subjects with the common 34C > T nonsense variant (rs17602729) of adenosine monophosphate dea...

objectives: we have investigated the effect of a saffron supplement, given at a dose of 100 mg/kg, on prooxidant-antioxidant balance (pab) in individuals with metabolic syndrome. materials and methods: a randomized, placebo-controlled trial design was used in 75 subjects with metabolic syndrome who were randomly allocated to one of two study groups: (1) the case group received 100mg/kg saffron ...

Caffeine is a commonly used neurostimulant that also produces cerebral vasoconstriction by antagonizing adenosine receptors. Chronic caffeine use results in an adaptation of the vascular adenosine receptor system presumably to compensate for the vasoconstrictive effects of caffeine. We investigated the effects of caffeine on cerebral blood flow (CBF) in increasing levels of chronic caffeine use...

OBJECTIVE We investigated the effect of caffeine ingestion on insulin sensitivity in sedentary lean men (n = 8) and obese men with (n = 7) and without (n = 8) type 2 diabetes. We also examined whether chronic exercise influences the relationship between caffeine and insulin sensitivity in these individuals. RESEARCH DESIGN AND METHODS Subjects underwent two hyperinsulinemic-euglycemic clamp p...