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Dysfunctions of COVID-19
Published in Wenguang Xia, Xiaolin Huang, Rehabilitation from COVID-19, 2021
Oxygen uptake reflects the body’s ability to absorb and consume oxygen, which is determined by the level of oxygen demand in cells and the maximum amount of oxygen transport. Oxygen uptake can be calculated by oxygen uptake into the bloodstream and tissues. Maximal oxygen uptake (VO2max) is the most important index to reflect aerobic capacity and exercise potential. Factors affecting oxygen uptake include oxygen-carrying capacity of blood, cardiac function, peripheral blood flow redistribution, tissue uptake, etc. The relationship between heart rate and oxygen uptake is usually nonlinear in low power motion but becomes nearly linear when the power gradually increases to the maximum. When an age-predicted heart rate is reached during exercise, it usually reflects that the patient has made the most effort and is close to reaching VO2max. The difference between the heart rate predicted by age and the maximum heart rate during exercise is the heart rate reserve. For COVID-19 patients, after correction of hypoxemia, anemia, and hypoproteinemia, tachycardia in calm state and low metabolic equivalent during exercise exceed the predicted value, both of which reflect the patient’s reduced exercise ability.
Coffee as a Functional Beverage
Published in Robert E.C. Wildman, Richard S. Bruno, Handbook of Nutraceuticals and Functional Foods, 2019
Victoria Burgess, Lem Taylor, Jose Antonio
Caffeine has been shown to improve performance and increase endurance during prolonged exercise, and in smaller amounts in shorter-term endurance performance.4, 22 This enhanced performance in endurance exercise is typically not associated with elevations in VO2 max and/or any parameters related to it, but it could allow an individual to compete at a higher power output or give the ability to train longer.23 Other reported benefits include a reduction in perceived leg pain induced by exercise24 and improved psychomotor performance (reaction time) during exercise.2 Improved concentration, improved cognitive performance after exercise,25 a reduction or delay in fatigue,26 and enhancement in alertness22 have also been reported. The benefits of caffeine consumption are clear. The evidence supporting a functional role for coffee consumption on exercise performance is discussed next.
Physical fitness development and its relationship to cognition
Published in Michael Horvat, Ronald V. Croce, Caterina Pesce, Ashley Fallaize, Developmental and Adapted Physical Education, 2019
Michael Horvat, Ronald V. Croce, Caterina Pesce, Ashley Fallaize
From basic physiology, you will recall that metabolism increases proportionally to increases in workload. However, when faced with increasingly higher energy demands, the body ultimately reaches a limit for oxygen consumption. At this point, oxygen consumption peaks and remains constant even with increasing workloads. This peak value is often referred to as maximal oxygen uptake (VO2 max), maximal aerobic power (capacity), or simply cardiorespiratory endurance capacity or aerobic fitness and is often regarded as the best single measure of cardiorespiratory endurance and aerobic fitness (Armstrong, 2013; Rowland, 2005).
COVID-19 reduces cardiorespiratory fitness even months after a mild to moderate acute phase: a retrospective cohort study
Published in Infectious Diseases, 2023
Ladislav Štěpánek, Marie Nakládalová, Eliška Sovová, Lubomír Štěpánek, Alena Boriková, Markéta Sovová, Katarína Moravcová, Jaromír Ožana, Libor Jelínek
The obtained results show that with similar mean values at baseline in both subgroups of HCWs, VO2 max decreased statistically significantly between examinations in the subgroup that experienced COVID-19. Mean VO2 max did not change significantly in the subgroup that did not experience COVID-19. VO2 max is the gold standard expression of cardiorespiratory fitness and aerobic capacity, and is also a strong predictor of all-cause and case-specific mortality and morbidity [13]. An individual’s VO2 max should be considered in the context of what is normal for that person. It is known that VO2 max decreases with age and that higher values are observed in men compared to women. Therefore, it is important to have predicted reference values for comparison when assessing VO2 max [14]. In HCWs with a history of COVID-19, the proportion of individuals reaching predicted values decreased between both cardiopulmonary exercise tests, but without statistical significance, which can be attributed to the relatively small number of HCWs in the COVID-19 subgroup. In the control subgroup, however, a slightly greater proportion of HCWs achieved the predicted VO2 max values during the second cardiopulmonary exercise testing compared with the first test.
Ubiquitin Proteasome System Activity is Suppressed by Curcumin following Exercise-Induced Muscle Damage in Human Skeletal Muscle
Published in Journal of the American College of Nutrition, 2021
Thomas D. Cardaci, Steven B. Machek, Dylan T. Wilburn, Paul S. Hwang, Darryn S. Willoughby
Total body mass (kg) was determined on a standard dual beam balance scale (Detecto Bridgeview, IL, USA). Body composition analyses were determined using DEXA (Hologic Discovery Series W, Waltham, MA, USA). Quality control calibration procedures were performed on a spine phantom prior to each testing session. Total body water was determined by bioelectric impedance spectroscopy (ImpediMed Ltd., Australia). Based on previous studies in our laboratory, the accuracy of the DEXA for body composition assessment is ±3.7% as assessed by direct comparison with hydrodensitometry and scale weight (37–39). In order to determine maximal aerobic capacity (VO2max), participants performed a volitional maximal cardiopulmonary exercise (VO2max) test on a laboratory treadmill using the Bruce protocol (40). Participants were instructed to perform the test for as long as possible to ensure a true maximal attempt. Standard ACSM test termination criteria were monitored and followed throughout each test. Metabolic gases were obtained with the Parvo Medics 2400 TrueMax metabolic measurement system (Parvo Medics, Sandy, Utah) to determine maximal aerobic capacity. The mean coefficient of variation for this protocol has previously been shown to be 6.5% (range 2%–14%) (40). Participant dietary intakes were not standardized; however, participants were instructed not to change their diet throughout the duration of the study.
Chronic Beetroot Juice Supplementation Accelerates Recovery Kinetics following Simulated Match Play in Soccer Players
Published in Journal of the American College of Nutrition, 2021
Wael Daab, Mohamed Amine Bouzid, Mehdi Lajri, Mustapha Bouchiba, Mohamed Ali Saafi, Haithem Rebai
The effect of beetroot juice supplementation on several aspects of exercise performance and physiological reponses has been well studied before. Bailey et al. (38) demonstrated a reduced PCr degradation with 500 mL of beetroot juice supplemntation following an incremental leg extension test. Moreover, Flanagan et al. (39) showed that 3 days of dietary nitrate supplementation increase average EMG amplitude during maximal isometric voluntary contractions. The authors concluded that nitrate-rich dietary supplementation was responsible of the improvement of neuromuscular efficiency. In the same way, Thompson et al. (23) showed that beetroot juice supplementation for 7 days was able to enhance repeated sprint performance (23). Recently, de Castro et al. (40) showed that 3 days of natural BET improved VO2max, speed at VO2max and speed peak in recreational runners.