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A Randomized Crossover Trial on the Acute Cardiovascular Demands During Flywheel Exercise.

ABSTRACT: In a randomized crossover trial, we examined whether age plays a role in the mean arterial pressure (MAP) response during a vigorous flywheel exercise of varying load. We hypothesized that the magnitude of increase in the MAP during the flywheel exercise would increase in proportion to advancing age, thereby imposing a significant challenge to the cardiovascular system. A total of 30 participants of both sexes (age range from 20-55 y, 37% women) underwent a detailed medical examination, and their maximal oxygen uptake was determined. They performed a squat exercise (2 sets × 7 repetitions) on a flywheel ergometer at three randomly assigned moments of inertia set at 0.025, 0.05, and 0.075 kg m², while the cardiovascular response was continuously recorded via a Task force monitor. Compared to the resting values, robust rises in the MAP were observed during all three flywheel loads, reaching the highest value of 179 ± 4 mmHg (p = 0.001) during the highest load. In parallel, the cardiac index (cardiac output normalized by the body surface area) was two-fold greater during all the flywheel loads compared to rest, and at a high load, exclusively, the total peripheral resistance increased by 11% (p = 0.001). The rise in heart rate compensated for a load-dependent drop in the stroke index (stroke volume normalized by the body surface area). In our study population, no correlations were observed between the relative increase in the MAP and the participants' age for the three flywheel loads. The present findings suggest that the larger moments of inertia impose a substantial burden to the cardiovascular system, without apparent associated age-differences of the relative magnitude of MAP rise throughout the exercise.

SUBMITTER: Zubac D

PROVIDER: S-EPMC8267577 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Project description:BackgroundMany breast cancer survivors (BCS) report deficits in cognitive function. Physical activity (PA) has been associated with better processing speed and memory in healthy adults and thus may be a useful method for improving cognition in BCS. The purpose of this study was to examine the effects of an acute bout of PA on processing speed and spatial working memory in a sample of BCS.MethodsUsing a repeated measures, crossover design, BCS [N = 27; Mage (SD) = 49.11(8.05)] completed two sessions in counterbalanced order: 30 min of moderate-intensity treadmill walking and 30 min of seated rest. Women completed cognitive tasks immediately before and after each session.ResultsWithin-subjects repeated measures analyses of variance revealed a significant time by session effect for processing speed reaction time [F (1,25) = 5.02, p = .03, η2 = 0.17]. This interaction was driven by significantly reduced reaction time (e.g., faster response) post-exercise and no change post-rest. Further between-subjects analyses indicated a significant time by session by moderate to vigorous physical activity (MVPA) split [F (1,25) = 5.23, p = .03, η2 = 0.17], such that women who engaged in ≥45 min of average daily MVPA reduced their reaction time post-exercise (p = .01) and increased RT post-rest (p = .06). Time by session effects for spatial working memory 3-item accuracy and 4-item reaction time trended towards significance, p = 0.08 and p = 0.10, respectively, again driven by better performance post-exercise.ConclusionsThe moderate effect of acute exercise on domains of memory and processing speed in BCS is encouraging. Cancer-related cognitive impairment remains largely misunderstood; however, the results from the present study offer preliminary evidence for the positive relationship between acute exercise and cognition in BCS.Trial registrationClinicalTrials.gov NCT02592070 . Registered 30 October 2015. Retroactively registered.

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A Randomized Crossover Trial on the Acute Cardiovascular Demands During Flywheel Exercise.

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