Cardiovascular control during exercise in type 2 diabetes mellitus.
Controlled studies of male and female subjects with type 2 diabetes mellitus (DM) of short duration (~3-5 years) show that DM reduces peak VO2 (L·min(-1) and mL·kg(-1)·min(-1)) by an average of 12-15% and induces a greater slowing of the dynamic response of pulmonary VO2 during submaximal exercise. These effects occur in individuals less than 60 years of age but are reduced or absent in older males and are consistently associated with significant increases in the exercise pressor response despite normal resting blood pressure. This exaggerated pressor response, evidence of exertional hypertension in DM, is manifest during moderate submaximal exercise and coincides with a more constrained vasodilation in contracting muscles. Maximum vasodilation during contractions involving single muscle groups is reduced by DM, and the dynamic response of vasodilation during submaximal contractions is slowed. Such vascular constraint most likely contributes to exertional hypertension, impairs dynamic and peak VO2 responses, and reduces exercise tolerance. There is a need to establish the effect of DM on dynamic aspects of vascular control in skeletal muscle during whole-body exercise and to clarify contributions of altered cardiovascular control and increased arterial stiffness to exertional hypertension.
School of Science and Health, University of Western Sydney, Sydney, NSW 2751, Australia ; Neuroscience Research Australia, Sydney, NSW 2751, Australia.
Simon
S
Green
Department of Physiology, School of Medicine, Trinity College Dublin, Dublin 1, Ireland.
Mikel
M
Egaña
Department of Medicine, University of Otago, Dunedin, Otago 9054, New Zealand.
J Chris
JC
Baldi
Department of Physiology-HeartOtago, University of Otago, Dunedin, Otago 9054, New Zealand.
Regis
R
Lamberts
Division of General Internal Medicine, Center for Women's Health Research, Department of Medicine, School of Medicine, University of Colorado, Denver, CO 80210, USA.
Judith G
JG
Regensteiner
D062186:Arterial Pressure; D001794:Blood Pressure; D002302:Cardiac Output; D002319:Cardiovascular System; D003924:Diabetes Mellitus, Type 2 / Q000378:metabolism*; D015444:Exercise / Q000502:physiology*; D017079:Exercise Tolerance; D005260:Female; D006339:Heart Rate; D006801:Humans; D006973:Hypertension / Q000503:physiopathology; D008168:Lung / Q000378:metabolism; D008297:Male; D008875:Middle Aged; D018482:Muscle, Skeletal / Q000378:metabolism; D010100:Oxygen / Q000737:chemistry; D010101:Oxygen Consumption; D059289:Vascular Stiffness; D014664:Vasodilation
D010100:Oxygen