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Cardiopulmonary exercise testing
Published in Jonathan Dakin, Mark Mottershaw, Elena Kourteli, Making Sense of Lung Function Tests, 2017
Jonathan Dakin, Mark Mottershaw, Elena Kourteli
The most commonly employed CPET protocol employs a progressively incremental workload which continues until exercise cannot be sustained or physiological parameters necessitate exercise termination. For most reliable results, the incremental exercise period should last between 8 and 12 minutes. The rate of workload increase is selected according to the predicted , age, gender and habitual levels of activity of the subject.
Nutritional Ergogenic Aids: Introduction, Definitions and Regulatory Issues
Published in Ira Wolinsky, Judy A. Driskell, Nutritional Ergogenic Aids, 2004
Ira Wolinsky, Judy A. Driskell
The effects of the drug on speed and power output during short-term intense exercise are summarized in Table 17.5. The limited number of studies and the heterogeneous experimental designs preclude drawing unequivocal conclusions. For example, caffeine ingestion has been reported to increase maximal anaerobic power during a force-velocity test,169 and also mean power output during rowing,170,171 but to have no effects on mean power sustained during a mock test172 or on anaerobic power, anaerobic capacity and rate of power loss during the 30-s Wingate test.102 Similarly, no effects on peak power, average power and rate of power loss were observed during a sequence of four repeated Wingate tests and, in fact, performance was impaired during the last two bouts in the caffeine trials.95 On the other hand, the results of the studies measuring speed in time trials during running,173 swimming174 and rowing170,171 demonstrate a clear ergogenic effect of the drug. Interestingly, an improvement in swimming velocity was noted only in well-trained swimmers and not in recreational ones.174Incremental Exercise
Power versus endurance
Published in Francesco E. Marino, Human Fatigue, 2019
While these models of endurance continue to be debated, the traditional method used to determine endurance is still the VO2max test, whereby an individual either runs on a treadmill or cycles on a stationary ergometer, commencing with a low speed or power output with progressive increments until voluntary termination or exhaustion. The prediction of the classic understanding of exercise limitation is that oxygen consumption during increasing intensity should level off since the delivery (cardiac output) and the usage (skeletal muscle) of oxygen for the generation of ATP through oxidative processes should be at their limit. An early description suggested that when exercise is at its limit – at exhaustion – oxygen consumption should plateau (Taylor et al. 1955). This is an essential outcome if the model predicts that exercise terminates because there is hypoxia-induced failure of mitochondrial ATP production which leads to fatigue. It is also an essential outcome because training studies show that improvements in VO2max are a result of either enhanced delivery of oxygen to the tissues or increased capillarisation and mitochondrial capacity (Daussin et al. 2007). As is shown in Figure 9.4, when oxygen consumption is continuously sampled and is then plotted against increasing work rate, oxygen consumption increases somewhat linearly early on and then slows as exercise intensity increases. What is also evident from the top panel is that oxygen consumption for a particular individual shows an asymptote rather than a true plateau, whereas in the bottom panel a plateau for a different individual is never attained. The data shown in Figure 9.4 are redrawn and based primarily on those provided in the classic study of Wyndham et al. (1959). When these authors assessed these data, they suggested that the VO2max value should be based on the mean of three values falling on the asymptote, with the caveat being that these points should not differ more than 0.15 l/min. The issue here is that the plateau in oxygen consumption during maximal incremental exercise is as common as it is elusive. In fact, the literature dealing with this topic is littered with studies that show a plateau in oxygen consumption is identified in only a fraction of the population studied. For example, see Cumming and Borysyk (1972) and Myers et al. (1989).
Influence of personality and self-efficacy on perceptual responses during high-intensity interval exercise in adolescents
Published in Journal of Applied Sport Psychology, 2021
Adam A. Malik, Craig A. Williams, Kathryn L. Weston, Alan R. Barker
With regard to self-efficacy (i.e., confidence to perform the exercise task), a review of research in adolescents has indicated self-efficacy as a prominent personal determinant to engage with physical activity behavior (Van Der Horst, Paw, Twisk, & Van Mechelen, 2007). Bandura (1986) argued that there is a link between affective responses and the subsequent formation of individual self-efficacy (i.e., pleasurable feelings may reflect high confidence level and unpleasant feelings may reflect low confidence level). Previous studies in adults have consistently reported that individuals with high self-efficacy exhibit more positive affect and a lower rating of perceived exertion (RPE) compared to low self-efficacy individuals during exercise (Focht, 2013; McAuley & Courneya, 1992; Tate, Petruzzello, & Lox, 1995). These authors revealed that the differences between low vs. high self-efficacy individuals were increasingly evident at more demanding work intensities (e.g., above 70% of predicted maximal heart rate). However, these observations were limited to incremental exercise to exhaustion and continuous exercise in adults, which is untypical of youth patterns of activity and exercise (Barkley, Epstein, & Roemmich, 2009).
Influence of time of day and intermittent aerobic exercise on vascular endothelial function and plasma endothelin-1 in healthy adults
Published in Chronobiology International, 2021
Kevin D. Ballard, Roshan Timsina, Kyle L. Timmerman
Prior to the screening visit, participants were instructed to fast overnight, abstain from caffeine for 12 h, and abstain from alcohol and strenuous exercise for 24 h. After obtaining written informed consent, participants were familiarized with the equipment and exercise protocol. Height, weight, waist circumference (umbilicus), and resting heart rate (HR) and blood pressure were measured using standard procedures, and health history, physical activity, and menstrual history questionnaires (women only) were completed. Body composition was measured with bioelectrical impedance (InBody 770, Cerritos, CA). A blood sample was obtained via finger stick for the determination of fasting blood lipid and glucose concentrations (Cholestech LDX Analyzer, Abbott, Abbott Park, IL) (Table 1). Next, participants were familiarized with the equipment and exercise protocol. VO2peak and peak Watts were determined using an incremental exercise protocol to exhaustion on a cycle ergometer (SCIFIT PRO2, Life Fitness, Rosemont, IL). The incremental exercise test began at 25 W for 3 min and progressed in 25 W increments every 2 min until volitional exhaustion or the participant could no longer maintain the required cadence (≥60 rpm). HR and rating of perceived exertion (RPE) were assessed at the end of each stage during the incremental exercise test. Expired gases were collected and sampled every 30 s (ParvoMedics, Sandy, UT). The exercise work rate corresponding to 70% peak Watts was determined.
Patients recovering from exacerbations of COPD with and without hospitalization need: could ICF score be an additional pulmonary rehabilitation outcome?
Published in Annals of Medicine, 2021
Michele Vitacca, Laura Comini, Anna Giardini, Adriana Olivares, Giacomo Corica, Mara Paneroni
At the time of rehabilitative in-hospital admission, each patient received a multidisciplinary pulmonary rehabilitation program (PRP) according to the Clinical Care Pathway (CCP) [7]. A multidisciplinary team consisting of chest physicians, nurses, physiotherapists, dieticians, and psychologists offered care. Our in-patient multidisciplinary program included the optimization of drug therapy, education, nutritional programs, and psychosocial counselling when appropriate, and at least 22 sessions for 3–4 weeks, of supervised incremental exercise training according to Maltais et al. [15], until performing 30 min of continuous cycling at 50–70% of the maximal load calculated based on the baseline 6MWD according to Luxton et al. [16]. Peripheral limb muscle activities, shoulder, and full arm circling were also performed. Supplemental oxygen for patients under LTOT and interval training for most compromised patients weredelivered. Pulse oximetry and rate, and arterial blood pressure were monitored during exercise. The total daily time duration of activities was 2–3 h.