Premium
Cardiac response to exercise in normal‐weight and obese, Hispanic men and women: implications for exercise prescription
Author(s) -
Vella C. A.,
Paul D. R.,
Bader J.
Publication year - 2012
Publication title -
acta physiologica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.591
H-Index - 116
eISSN - 1748-1716
pISSN - 1748-1708
DOI - 10.1111/j.1748-1716.2011.02371.x
Subject(s) - medicine , cardiac output , vo2 max , body mass index , stroke volume , cardiology , cardiac index , cardiac function curve , ejection fraction , exercise prescription , heart rate , obesity , endocrinology , blood pressure , physical therapy , heart failure
Aim: The effects of obesity on cardiac function during incremental exercise to peak oxygen consumption ( V O 2peak ) have not been previously described. The purpose of this study was to compare submaximal and maximal cardiac function during exercise in normal‐weight and obese adults. Methods: Normal‐weight ( n = 20; means ± SE: age = 21.9 ± 0.5 years; BMI = 21.8 ± 0.4 kg m −2 ) and obese ( n = 15; means ± SE: age = 25.1 ± 5.2 years; BMI = 34.1 ± 01.0 kg m −2 ) participants were assessed for body composition, V O 2peak and cardiac variables (thoracic bioimpedance analysis) at rest and at heart rates (HR) of 110, 130, 150 and 170 beats min −1 and maximal HR during incremental cycling exercise to exhaustion. Differences between groups were assessed with mixed‐model ancova with repeated measures. Cardiac variables were statistically indexed for body surface area and resting HR. V O 2 and arteriovenous oxygen difference (a‐ v O 2 ) were statistically indexed for fat‐free mass and resting HR. Results: Significant main effects for group indicated obese participants had higher cardiac output (Q) index and stroke volume (SV) index but lower ejection fraction (EF) and a‐ v O 2 index during incremental exercise to exhaustion compared with their normal‐weight peers, despite similar submaximal and maximal V O 2 and absolute power outputs ( P < 0.05). Conclusions: Our findings suggest that although Q index and SV index were higher in obese, young adults, EF and a‐ v O 2 index were significantly lower when compared to matched, normal‐weight adults.