Microvascular distribution is a key in determining efficacy of peripheral O2transport. Angiogenesis, growth of capillaries from a pre-existing network, is driven by a range of chemical and mechanical factors. Although often described in global terms, we have demonstrated that neovascularisation in skeletal muscle is effected on a lengthscale approximating the diameter of individual fibres. To characterise the complex local feedback required for such tight regulation of the growth process, it is necessary to quantify both structural and functional responses following stimulation of angiogenesis in a physiological context. Sustained skeletal muscle hyperaemia (predominantly mechanical stimulus) was induced by prazosin (PRAZ: 50 mg l−1) given ad libitum in drinking water, while overload (OV: mechanical stimulus that also invokes an anabolic, chemical stimulus) induced by surgical extirpation of the tibialis anterior, results in extensor digitorum longus (EDL) hypertrophy. Animals were sampled after 7 or 14 days. Simultaneous recordings were made of hindlimb (femoral artery) perfusion with a Transonic® flow probe and EDL twitch force by an Aurora® force transducer system. Fatigue resistance was quantified with 10Hz twitches (0.3ms pulse width, supramaximal voltage) for 180s, and fatigue index (FI) calculated as end-stimulation tension/peak tension at the start of the test. Muscles were frozen in liquid N2 cooled isopentane, and 10µm cryosections were stained with G. simplicifolia lectin-1 (Vector). FI was improved in 7d and 14d OV EDL compared to control (P<0.05) and PRAZ (P<0.01) animals (all n=5), but there was no effect of PRAZ on FI compared to control (P=0.94), and no difference in FI between 7d and 14d treatments. Resting femoral flow was enhanced with PRAZ relative to control (P≤0.05) and OV animals (P<0.05), with no difference between end-stimulation blood flow among treatments (P>0.05). When considering global microvascular supply, capillary to fibre ratio (C:F) at 7d (1.90±0.08, n=5) and 14d OV (1.85±0.11, n=3), as well as 14d PRAZ (1.72±0.07, n=4), were all significantly (P<0.05) higher than control tissue (1.43±0.02, n=6). Fibre cross-sectional area (FCSA) after 14d OV (2660±350 µm2) was significantly higher than control (1629±86 µm2). Examining local capillary distribution, by the capillary domains technique (Al-Shammari et al. 2019. J Appl Physiol 126:544-557), allowed capillary-spacing heterogeneity to be quantified as LogSD of supply area to account for the log-normal distribution. LogSD after 7d OV (0.16±0.01) was significantly (P<0.01) reduced compared to control (0.19±0.01) and 7d PRAZ (0.18±0.01). These data show that a haemodynamic signal alone can elicit an angiogenic response, with little effect on muscle fatigability and a stochastic location of new vessels, while a combination of mechanical and chemical stimulation improves muscle function and is associated with directed location of capillaries to optimise O2 delivery.