Seeking to develop a simple ambulatory test of maximal aerobic power (VO(2 max)), we hypothesized that the ratio of inverse foot-ground contact time (1/t(c)) to heart rate (HR) during steady-speed running would accurately predict VO(2 max). Given the direct relationship between 1/t(c) and mass-specific O(2) uptake during running, the ratio 1/t(c). HR should reflect mass-specific O(2) pulse and,...

On the basis of cross-sectional data, we previously reported that the absolute, but not the relative (%), rate of decline in maximal oxygen consumption (VO(2 max)) with age is greater in endurance-trained compared with healthy sedentary women. We tested this hypothesis by using a longitudinal approach. Eight sedentary (63 +/- 2 yr at follow-up) and 16 endurance-trained (57 +/- 2) women were ree...

Inspiring a hyperoxic (H) gas permits subjects to exercise at higher power outputs while training, but there is controversy as to whether this improves skeletal muscle oxidative capacity, maximal O(2) consumption (Vo(2 max)), and endurance performance to a greater extent than training in normoxia (N). To determine whether the higher power output during H training leads to a greater increase in ...

CONTEXT A common variant in the first intron of FTO (rs9939609, T/A) is associated with fatness in Caucasians. OBJECTIVE FTO may regulate energy homeostasis through the hypothalamus, and we hypothesized that AA-genotypes of rs9939609 FTO have lower energy expenditure and/or a lower level of physical activity. METHODS The study population included all obese young men (body mass index > or = ...

BACKGROUND Dyspnea and fatigue are the main causes of exercise limitation in chronic heart failure (CHF) patients, whose peak inspiratory (Pi(max)) and expiratory pressures (Pe(max)) are often reduced. The aim of this study was to examine the relationship between respiratory muscle performance and oxygen kinetics. METHODS AND RESULTS A total of 55 patients (NYHA class I to III) and 11 healthy...

Exercise performance in chronic heart failure is severely impaired, due in part to a peripherally mediated limitation. In addition to impaired maximal exercise capacity, the O(2) uptake (VO(2)) response during submaximal exercise may be affected, with a greater reliance on anaerobiosis leading to early fatigue. However, the response of VO(2) kinetics to submaximal exercise in chronic heart fail...

BACKGROUND Oral contraceptives are commonly used by women athletes. However, their effect on athletic performance is unclear. OBJECTIVES To examine the effects of a moderate dose, triphasic oral contraceptive on measures of athletic performance in highly trained women athletes. METHODS This is a double blind, placebo controlled trial in 14 women with ovulatory menstrual cycles and maximal a...

Plasma glucose and muscle glycogen oxidation during prolonged exercise [75-min at 48 and 76% maximal O(2) uptake (Vo(2 max))] were measured in eight well-trained male subjects [Vo(2 max) = 4.50 l/min (SD 0.63)] using a simplified tracer technique in which a small amount of glucose highly enriched in (13)C was ingested: plasma glucose oxidation was computed from (13)C/(12)C in plasma glucose (wh...

BACKGROUND Low cardiorespiratory fitness is considered to be a major public health problem. We examined the relationship of cardiorespiratory fitness, as indicated by maximum oxygen consumption VO(2)max with subsequent incidence of stroke. We also compared VO(2)max with conventional risk factors as a predictor for future strokes. METHODS Population-based cohort study with an average follow-up...

AIM To determine if there are correlations between the physical fitness of young soccer players assessed by field and laboratory testing. METHODS Thirty four male soccer players took part in the study (mean (SD) age 17.5 (1.1) years, height 177.8 (6.7) cm, weight 70.5 (6.4) kg). Maximal oxygen uptake (VO(2)MAX) during treadmill running and vertical jump height on a force platform were measure...