Factors associated with resting capillary blood volume. The panel A describes the relationship between age (years) and resting capillary blood volume available for gas exchange (VC, mL) in inactive (closed circles) and endurance-trained (open circles) men. A significant relationship is evidenced (see Table 2). The panel B describes the relationship between the vigorous-intensity activity domain of the International Physical Activity Questionnaire (Vigorous-IPAQ) and resting VC. A significant relationship is evidenced (see Table 2). The panel C describes the relationship between resting VC and expressed as raw values, while the panel D describes the relationship between normalized for age and height (expressed as% predicted, see Table fourteen in ). The statistical significance of the relationship of panel C is given in Table 2. The significance of the relationship of panel D (r = 0.311, p = 0.013) further suggests that VC is an independent (of age and height) predictor of .