Abstract

Purpose: Leg venous compliance decreases with age, but subjects with high fitness show less venous remodelling than unfit subjects. Whether a high fitness level can counteract the normal age-decline in upper arm venous compliance is unknown.

Study aim: First, to examine upper arm venous compliance across age in participants with comparable levels of maximal oxygen uptake (VO_2max). Second, to examine if upper arm venous compliance is related to total blood volume.

Methods: Twenty-eight healthy fit participants within the age groups 20-39 (young: VO_2max 3.44 (2.35–5.09) L∙min^-1, n=9), 40-59 (middle-aged: VO_2max 3.08 (2.17-4.60) L∙min^-1, n=9), and 60-69 (old: VO_2max 3.27 (2.24–4.04) L∙min^-1, n=10) years of age were recruited to the study. Upper arm venous compliance was examined using high-resolution ultrasound and Doppler, while total blood and plasma volume were measured using the optimized carbon monoxide (CO)-rebreathing method.

Results: No difference was found in upper arm venous compliance normalized to blood volume in participants aged 20-69 years (young: 0.22 (-0.02–0.5) mm³∙mmHg^-1∙L^-1, middle aged: 0.05 (-0.1–0.4) mm³∙mmHg^-1∙L^-1, old: 0.16 (0.1–0.5) mm³∙mmHg^-1∙L^-1) with comparable high VO_2max levels.

Conclusion: In the studied subjects between 20-70 years old with comparable absolute VO_2max, upper arm venous compliance normalized to blood volume seems to be age independent.

Keywords: Veins, age, VO_2max, blood volume