Little is known of the vasomotor responses of skeletal muscle arterioles during and following muscle contraction. We hypothesized that aging impairs arteriolar responses to muscle contraction and recovery. Nitric oxide (NO) availability, which is age-dependent, has been implicated in components of these kinetics. Therefore, we also hypothesized that changes in the kinetics of vascular responses are associated with the NO pathway. Groups were young (3 mo), old (24 mo), endothelial NO synthase knockout (eNOS-/-) and N-nitro-L-arginine (LNA) -treated male and female C57BL6 mice. The kinetics of vasodilation during and following 1 min of contractions of the gluteus maximus muscle were recorded in second order (2A, regional distribution) and third order (3A, local control) arterioles. Baseline, peak (during contraction) and maximal diameters (pharmacologic) were not affected by age or sex. The kinetics of dilation and recovery were not different between males and females at the young age. There was a slowing of vasodilation at the onset of contractions (~2-fold; p<0.05) and a speeding of recovery (~5-fold; p<0.05) in old males vs old females and vs young . eNOS-/- and LNA did not affect the kinetics at the onset of contractions. eNOS-/- mimicked the rapid recovery of old males in 2A; acute NOS production (LNA) explained ~50% of this effect. These data demonstrate age-related differences between the sexes in the dynamic function of skeletal muscle arterioles. Understanding how youthful function persists in females may provide therapeutic insight into clinical interventions to maintain dynamic microvascular control of nutrient supply with age.