Modulation of Vascular Function by Diet and Exercise

Abstract

Clinical research is conducted in free living individuals who are always subject to the influences on vascular function and the major cardiovascular regulators of their lifestyle. The purpose of this paper is to review some lifestyle influences on cardiovascular function, particularly the sympathetic nervous system and endothelially mediated vasodilatation. There are highly differentiated sympathetic responses to feeding, and to acute exercise. Over a longer period obesity has a typical pattern of sympathetic activity. Reduced dietary salt intake elicits profound localised increases in sympathetic activity to the kidney. Marine oil supplementation attenuates the sympathetic responses to psychological stress and improves endothelially mediated vasodilatation in hypercholesterolaemics. Exercise training reduces total noradrenaline spillover, the major beds affected being the renal and skeletal muscle. These examples illustrate the dynamic nature of vascular dilatation and that, like the sympathetic nervous system, it is modulated by short, medium and long term influences. In both cases there is regulation both at a local and systemic level. Habitual, and recent, lifestyle can exert important cardiovascular effects which must be taken into account in clinical and epidemiological research.

Key Words:

• Diet
• exercise
• sympathetic activity
• endothelium
• nitric oxide
• cholesterol
• marine oils