Methods Fifteen (22.1 ± 2.7 years old) participants completed the study. Maximal oxygen consumption (VO2 max) was initially measured to establish each participant’s exercise for the 70% treadmill exercise protocol after ingesting an energy drink. Following VO2 max testing, all participants completed a total of four conditions. Each condition required a participant to ingest an energy drink then...

Persons with type II diabetes mellitus (DM), even without cardiovascular complications have a decreased maximal oxygen consumption (VO2 max) and submaximal oxygen consumption (VO2) during graded exercise compared with healthy controls. We evaluated the hypothesis that change in the rate of VO2 in response to the onset of constant-load exercise (measured by VO2-uptake kinetics) was slowed in per...

To unravel the mechanisms by which maximal oxygen uptake (VO2 max) is reduced with severe acute hypoxia in humans, nine Danish lowlanders performed incremental cycle ergometer exercise to exhaustion, while breathing room air (normoxia) or 10.5% O2 in N2 (hypoxia, approximately 5,300 m above sea level). With hypoxia, exercise PaO2 dropped to 31-34 mmHg and arterial O2 content (CaO2) was reduced ...

The relationship of maximal oxygen uptake (VO2 max) with dihydrogenated ergot alkaloids was investigated in twelve young men. They were subjected to graded bicycle exercise with work loads corresponding to 75% and 120% of the load necessary to elicit VO2 max. The exercise tests were performed after intravenous administration of 2 mg dihydroergostin (DE-145) as well as after saline as control, b...

Controversy exists regarding the relative importance of adiposity, physical fitness, and physical activity in the regulation of insulin-stimulated glucose disposal. To address this issue, we measured insulin-stimulated glucose disposal [mg. kg fat-free mass (FFM)(-1). min(-1); oxidative and nonoxidative components] in 45 nondiabetic, nonobese, premenopausal women (mean +/- SD; 47 +/- 3 yr) by u...

Previous investigators have reported that oxygen consumption (VO2) continues to rise after the initial 2- to 3-min transient period of exercise when work exceeds approximately 60% of VO2 max. The purpose of this investigation was to examine the possible causes of this slow rise in VO2. Eighteen subjects exercised for 20 min at 65% and at 80% of VO2 max on the bicycle ergometer. VO2, ventilation...

OBJECTIVE Little is known about levels of physical fitness in children from different ethnic groups in the UK. We therefore studied physical fitness in UK children (aged 9-10 years) of South Asian, black African-Caribbean and white European origin. DESIGN Cross-sectional study. SETTING Primary schools in the UK. PARTICIPANTS 1625 children (aged 9-10 years) of South Asian, black African-Ca...

The effect of oral doses of the beta 1-selective adrenoceptor antagonist atenolol (50 mg), the non-selective antagonist propranolol (40 mg) and placebo was investigated during exercise in a crossover comparison in six healthy but untrained subjects. Descriptors of ventilation, respiratory gas exchange, and arterialized blood lactate and glucose were obtained during steady state bicycle ergometr...