Serum Tumor Necrosis Factor-alpha associates with Myocardial Oxygen Demand and Exercise Tolerance in Postmenopausal Women
Year: 2018
Type: article
Study design: Observational Study
Abstract: International Journal of Exercise Science 11(2): 42-54, 2018. The functional implications of serum tumor necrosis factor-alpha (TNF-a), a marker of oxidative stress, on hemodynamic parameters at rest and during physical exertion are unclear. The aims of this investigation were to examine the independent associations of TNF-a on myocardial oxygen demand at rest and during submaximal exercise, while also evaluating the association of TNF-a on exercise tolerance. Forty, postmenopausal women, provided blood samples and completed a modified-Balke protocol to measure maximal oxygen uptake (VO2max). Large artery compliance was measured by pulse contour analyses while rate-pressure product (RPP), an index of myocardial oxygen demand, was measured at rest and during two submaximal workloads (i.e., ≈55% and ≈75% VO2max). RPP was calculated by dividing the product of heart rate and systolic blood pressure (via auscultation) by 100. Exercise tolerance corresponded with the cessation of the graded exercise test. During higher-intensity exertion, ≈75% VO2max, multiple linear regression revealed a positive association (r = 0.43; p = 0.015) between TNF-a and RPP while adjusting for maximal heart rate, VO2max, large artery compliance, and percent body fat. Path analyses revealed a significant indirect effect of large artery compliance on exercise tolerance through TNF-a, β = 0.13, CI [0.03, 0.35], indicating greater levels of TNF-a associated with poorer exercise tolerance. These data suggest TNF-a independently associates with myocardial oxygen demand during physical exertion, thus highlighting the utility of higher-intensity efforts to expose important phenomena not apparent at rest. TNF-a also appears to be indirectly associated with the link between large artery compliance and exercise tolerance.
DOI: 10.70252/prws2257
Institutions: University of Alabama at Birmingham, University of Kentucky
Language: English
Subfield: Complementary and alternative medicine
Field: Medicine
Domain: Health Sciences
Open Access status: diamond
Awards: UAB Center for Clinical and Translational Science (CCTS) UL1, G283777812, G3179975197, UAB Diabetes Research and Training Center, Frequency of aerobic/resistance training in older women, UAB Nutrition Obesity Research Center (NORC), UAB Pre-Doctoral Training Program in Obesity-Related Research
OpenAlex ID: W2781901995