Arm venous compliance and maximal oxygen uptake: adding age, cardiovascular disease, exercise and total blood volume to the discussion.
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Age and heart failure is associated with impaired arm venous function, indicating a negative effect of both age and heart failure on arm venous compliance. Positive associations have been found between cardiopulmonary fitness and leg venous compliance; however, diverging results are reported with regards to the association between arm venous compliance and cardiopulmonary fitness. Additionally, the role of blood volume in the determination of venous compliance is unknown. The overall aim of the present thesis was to investigate the effect of age, coronary artery disease, and blood volume on upper arm venous compliance. The present thesis compared healthy individuals (aged 20-69 years), stable coronary artery disease patients and overweight and obese individuals with similar VO2max/peak to examine whether age, coronary artery disease or overweight per se has an effect on upper arm venous compliance. No difference was found in upper arm venous compliance normalized to blood volume, indicating that total blood volume and VO2max/peak might be of importance for upper arm venous compliance. The present thesis also examined the effect of six weeks of exercise training with different durations and intensities on upper arm venous compliance. No change in upper arm venous compliance was found, despite increased VO2max after high intensity interval training. However, no change was found in total blood volume in either group. These results indicate that upper arm venous compliance will remain unchanged after high intensity interval training which increases VO2max, as long as blood volume is unchanged. In conclusion, this thesis shows that total blood volume and VO2max/peak might be of importance for upper arm venous compliance in ageing individuals (20-69 years of age), in patients with stable coronary artery disease (CAD), and in overweight and obese individuals. Additionally, the present thesis indicates that upper arm venous compliance will remain unchanged after high intensity interval training, which increases VO2max in overweight and obese participants as long as blood volume is unchanged.