Cardiovascular and cerebral hemodynamics during exercise and recovery in obese individuals as a function of their fitness status

Mathieu Gayda (1, 2, 3) , Gabriel Lapierre (2, 3) , Olivier Dupuy (4) , Sarah Fraser (5) , Louis Bherer (2, 3, 1) , Martin Juneau (2, 3, 1) , Vincent Gremeaux (6) , Anil Nigam (2, 3, 1)

1 Faculté de Médecine, Université de Montréal
2 Centre EPIC [Institut de Cardiologie de Montréal]
3 Montreal Heart Institute - Institut de Cardiologie de Montréal
4 MOVE [Poitiers] - Laboratoire Mobilité, Vieillissement, Exercice
5 University of Ottawa [Ottawa]
6 PIT - Plateforme d’Investigation Technologique [Centre d’Investigation Clinique 1432 module Plurithématique - Dijon]

The aim of this study was to compare cardiovascular hemodynamics and cerebral oxygenation/perfusion (COP) during and after maximal incremental exercise in obese individuals according to their aerobic fitness versus age-matched healthy controls (AMHC). Fifty-four middle-aged obese (OB) and 16 AMHC were recruited. Maximal cardiopulmonary function (gas exchange analysis), cardiac hemodynamics (impedance cardiography), and left frontal COP (near-infrared spectroscopy: NIRS) were measured continuously during a maximal incremental ergocycle test. During recovery, reoxygenation/perfusion rate (ROPR: oxyhemoglobin: Delta O(2)Hb, deoxyhemoglobin: Delta HHb and total hemoglobin: Delta tHb; with NIRS) was also measured. Obese participants (OB, n = 54) were divided into two groups according to the median VO2 peak: the low-fit obese (LF-OB, n = 27) and the high-fit obese (HF-OB, n = 27). During exercise, end tidal pressure of CO2 (PETCO2), and COP (Delta O(2)Hb, Delta HHb and Delta tHb) did not differ between groups (OB, LF-OB, HF-OB, AMHC). During recovery, PETCO2 and ROPR (Delta O(2)Hb, Delta HHb and DtHb) were similar between the groups (OB, LF-OB, HF-OB, AMHC). During exercise and recovery, cardiac index was lower (P < 0.05) in LF-OB versus the other two groups (HF-OB, AMHC). As well, systolic blood pressure was higher during exercise in the OB, LF-OB and HF-OB groups versus AMHC (P < 0.05). When compared to AMHC, obese individuals (OB, LF-OB, HF-OB) have a similar cerebral vasoreactivity by CO2 and cerebral hemodynamics during exercise and recovery, but a higher systolic blood pressure during exercise. Higher fitness in obese subjects (HF-OB) seems to preserve their cardiopulmonary and cardiac function during exercise and recovery.

Mots clés: diastolic dysfunction; cardiac-output; coronary-heart-disease; oxygenation; metabolic syndrome; normal-weight; Cardiac and cerebral hemodynamics; exercise; obesity; recovery; impedance cardiograph device; intensity interval exercise; near-infrared spectroscopy; men

Domaines: Physiologie [q-bio.TO]

Mathieu Gayda, Gabriel Lapierre, Olivier Dupuy, Sarah Fraser, Louis Bherer, et al.. Cardiovascular and cerebral hemodynamics during exercise and recovery in obese individuals as a function of their fitness status. Physiological Reports, 2017, 5 (12), pp.e13321. ⟨10.14814/phy2.13321⟩. ⟨hal-01588561⟩