Search results for " Oxygen uptake"

Exercise intolerance at high altitude (5050 m): critical power and W'.

2011

Abstract The relationship between work rate (WR) and its tolerable duration (tLIM) has not been investigated at high altitude (HA). At HA (5050 m) and at sea level (SL), six subjects therefore performed symptom-limited cycle-ergometry: an incremental test (IET) and three constant-WR tests (% of IET WRmax, HA and SL respectively: WR1 70 ± 8%, 74 ± 7%; WR2 86 ± 14%, 88 ± 10%; WR3 105 ± 13%, 104 ± 9%). The power asymptote (CP) and curvature constant (W′) of the hyperbolic WR–tLIM relationship were reduced at HA compared to SL (CP: 81 ± 21 vs. 123 ± 38 W; W′: 7.2 ± 2.9 vs. 13.1 ± 4.3 kJ). HA breathing reserve (estimated maximum voluntary ventilation minus end-exercise ventilation) was also comp…

Cardiorespiratory Changes During Prolonged Downhill Versus Uphill Treadmill Exercise

2020

AbstractOxygen uptake (V̇O2), heart rate (HR), energy cost (EC) and oxygen pulse are lower during downhill compared to level or uphill locomotion. However, a change in oxygen pulse and EC during prolonged grade exercise is not well documented. This study investigated changes in cardiorespiratory responses and EC during 45-min grade exercises. Nine male healthy volunteers randomly ran at 75% HR reserve during 45-min exercise in a level (+1%), uphill (+15%) or downhill (−15%) condition. V̇O2 , minute ventilation (V̇E ) and end-tidal carbon dioxide (PetCO2) were recorded continuously with 5-min averaging between the 10th and 15th min (T1) and 40th and 45th min (T2). For a similar HR (157±3 bpm…

Sex differences on peak oxygen uptake in heart failure

2019

Women represent nearly half of the adult heart failure (HF) population and they remain underrepresented in HF studies. We aimed to evaluate the evidence about peak oxygen uptake (peak VO2) for clinical stratification in women with HF. This narrative review summarizes (i) the evidence endorsing the value of cardiopulmonary exercise testing for clinical stratification and phenotyping HF population; (ii) the determinants of a person’s functional aerobic capacity to understand predicted values for patients with chronic HF; and (iii) sex differences on peak VO2 data in different forms of HF. Lastly, based on existing data in patients with HF, we provide a perspective on how to improve existing g…

VO2max Characteristics of Elite Female Soccer Players, 1989–2007

2013

Purpose:To quantify VO2max among female competitive soccer players as a function of performance level, field position, and age. In addition, the evolution of VO2max among world-class players over an 18-y period was quantified.Methods:Female players (N = 199, 22 ± 4 y, 63 ± 6 kg, height 169 ± 6 cm), including an Olympic winning squad, were tested for VO2max at the Norwegian Olympic Training Center between 1989 and 2007.Results:National-team players had 5% higher VO2max than 1st-division players (P = .042, d = 0.4), 13% higher than 2nd-division players (P < .001, d = 1.2), and 9% higher than junior players (P = .005, d = 1.0). Midfielders had 8% higher VO2max than goalkeepers (P = .048, d …

Recent advances in machine learning for maximal oxygen uptake (VO2 max) prediction : A review

2022

Maximal oxygen uptake (VO2 max) is the maximum amount of oxygen attainable by a person during exercise. VO2 max is used in different domains including sports and medical sciences and is usually measured during an incremental treadmill or cycle ergometer test. The drawback of directly measuring VO2 max using the maximal test is that it is expensive and requires a fixed and controlled protocol. During the last decade, various machine learning models have been developed for VO2 max prediction and numerous studies have attempted to predict VO2 max using data from submaximal and non-exercise tests. This article gives an overview of the machine learning models developed over the past five years (…

CIRCUIT WORKOUT TRAINING IN THE MORNING OR IN THE EVENING: EFFECTS ON BODY COMPOSITION AND INDIRECT MAXIMUM OXYGEN CONSUMPTION

2009

Association of cardio-pulmonary stress test parameters and heart rate recovery in obese subjects with or without type II diabetes

2016

Background and Objectives: Heart rate recovery at first (HRR-I) and second (HRR-II) minute after exercise is accurate in estimating autonomic nervous system balance, and has been related to risk of cardiovascular events. Our aim was to determine independent predictors of HRR collected during standard cardio-pulmonary stress test (CPT) in a group of overweight/obese subjects without (N=14) and with type 2 diabetes (N=19), as compared to a sample (N=15) of healthy sedentary subjects. Methods: A graded exercise test on treadmill was performed. Oxygen uptake at rest and at peak exercise (VO2max), as well as respiratory exchange ratio at peak exercise was collected. Linear and logistic regressio…

Physiological responses of running intermittent exercises

2012

The aims of the present work were to analyze the physiological responses during intermittent exercise and to determine; i) an field test to assess the maximal aerobic velocity (MAV) for intermittent exercise; ii) the type of intermittent exercise could elicit maximal oxygen uptake (VO2max); iii) the physiological and neuromuscular factors that could limit intermittent exercise duration.The first study demonstrated that the MAV (MAV45-15) reached at the end of an incremental intermittent (45s run/ 15s rest) field test (45-15FIT) was relevant to elicit a high percentage of VO2max during a 30s-30s intermittent training session. The second and third studies demonstrated that intermittent exerci…

Ultra Trail Performance is Differently Predicted by Endurance Variables in Men and Women

2020

AbstractThe study aimed to assess the relationship between peak oxygen uptake, ventilatory thresholds and maximal fat oxidation with ultra trail male and female performance. 47 athletes (29 men and 18 women) completed a cardiopulmonary exercise test between 2 to 4 weeks before a 107-km ultra trail. Body composition was also analyzed using a bioelectrical impedance weight scale. Exploratory correlation analyses showed that peak oxygen uptake (men: r=–0.63, p=0.004; women: r=–0.85, p < 0.001), peak speed (men: r=–0.74, p < 0.001; women: r=–0.69, p=0.009), speed at first (men: r=–0.49, p=0.035; women: r=–0.76, p=0.003) and second (men: r=–0.73, p < 0.001; women: r=–0.76, p=0.003) vent…

RELATIONSHIP BETWEEN MAXIMAL FAT OXIDATION AND OXYGEN UPTAKE: COMPARISON BETWEEN PATIENTS WITH TYPE 2 DIABETES AND HEALTHY SEDENTARY SUBJECTS

2014

The contribution of fat oxidation to energy production during exercise is influenced by intensity of exercise. The aim of this study was to assess the relationship between the highest value of fat oxidation rate (FATmax) and the oxygen uptake (VO2) in sedentary type 2 diabetes (T2D) patients vs healthy sedentary subjects. Sedentary T2D patients and healthy sedentary subjects were evaluated to a graded exercise test, and oxygen uptake and fat oxidation rate were detected. Data show that in T2D patients fat oxidation rate is not impaired and the positive linear correlation between FATmax and both VO2 and VO2max suggests that even in T2D patients the muscle oxidative capacity might increase in…