stresses must therefore be expected to be low. In this ‘bradytrophic’ situation, the provision of resistive exercise might engender increased blood flow in the absence of any substantial acceleration-induced shear strains in the conduit arteries. Of note, walking and running is associated with vertical accelerations of up to 10 g (Lafortune, 1991), meaning that the habitual activity in an ambulatory setting is indeed likely to provide acceleration-related endothelial shear stresses. One way of reconciling findings from this study with those from the aforementioned bed-rest studies, therefore, would be in assuming that acceleration-induced shear stress does have an effect upon resting diameter that is independent of flow-mediated shear stress and that his effect saturates under ambulatory conditions with habitual activities. Although the training loads differed significantly between RVE and RE group for the last four training sessions, training load progressio did not have any measurable effect on resting SFA diameters, as yielded by ANCOVA (P = 017, data not shown).