Cardiovascular Response Essay

Cardiovascular Response to Exercise

Introduction

The cardiovascular system, comprising of blood vessels, the heart, and blood, responds predictably with regards to the increased exercise demands (Centers for Disease Control and Prevention 62). In a sense, a series of cardiovascular changes take place in response to physical exercise for providing enough blood supply to the constricting muscles, to dissipate the energy produced by active muscles, and to maintain the supply of blood to vital organs of the body such as the brain and the heart (Agarwal et al. CC06). In this regard, cardiovascular response to exercise occurs with changes in heart rate, cardiac output, stroke volume, peripheral vascular resistance and blood pressure/arterial pressure,

In other words, the increase in stroke volume occurs as a result of improved ventricular force of contraction. Heterometric and homeometric control governs myocardial force of contraction. While homeometric control is independent of the myocardial fibres length at the end of diastole, heterometric control depends on this length of myocardial fibres at the diastole end and is mainly influenced by the venous return (Agarwal et al. CC06). The respiratory pump, as well as venoconstriction skeletal muscle pump, influences the rise in venous return during physical activity. The increased venous return results in end-diastolic volume increase, which generates stretching of ventricular muscle fibres causing an increase in stroke

At the dynamic exercise onset, oxygen consumption starts to increase, continues to rise through the initial time of sustained exercise, but then flattens as transport and uptake are increased adequately so that the consumption is matched to the demand (Laughlin S245). In the recovery stage, oxygen uptake will eventually surpass oxygen supply to a point at which oxygen consumption rate exceeds aerobic capacity resulting in oxygen