Endothelial dysfunction contributes to the progression of atherosclerotic disease. Recent studies suggest electrical stimulation (ES) has a beneficial effect on endothelial function. Additionally, local heating also enhances endothelial function via an increase in skin blood flow and shear stress. Interestingly, ES alone can lead to a small increase in skin blood flow, whereas the combination of ES and local heating could generate a synergistic effect on skin blood flow. Therefore, the aim of this study was to test the hypothesis that combined local heating and ES provide the additive improvement on endothelial function than heating and ES alone. On three separate visits, brachial artery flow‐mediated dilation (FMD), an index of endothelium‐dependent vasodilator function, was assessed before and immediately after 30‐min of exposure to electrical stimulation (ES), heating (Heat), or combined electrical stimulation and heating (ES+Heat) in seven young male subjects (Age; 22.3±1.8 years, BMI; 22.1±0.6 kg/m2, Mean±SE). ES was delivered by an electrical stimulator and surface electrodes (5×5cm) placed bilaterally over the right brachioradialis and extensor carpi ulnaris muscles. Heat was performed using a heating pad (42–43□) wrapped around the right forearm. Brachial blood flow and shear rate and forearm skin blood flow were measured throughout each intervention. Skin blood flow at 30 min was increased (% change from baseline) with Heat (300±64%, p=0.001) and ES+Heat (345±69%, p<0.001), but not ES alone (98±20%, p=0.182). Brachial shear rate at 30 min of ES+Heat was higher than that in Heat (ES+Heat vs. Heat. 168±13 vs. 101±14 sec−1, p=0.026). However, brachial shear rate in ES+Heat vs. ES alone did not differ (168±13 vs. 122±16 sec−1, p=0.162). Importantly, ES+Heat induced a significant increase in FMD after the intervention (Pre vs. Post. 4.5±0.4 vs. 6.7±0.7%, p=0.042), whereas FMD did not change with Heat alone (5.2±0.3% vs. 6.1±0.6%, p=0.342) and ES alone (4.8±0.4 vs. 5.0±0.8%, p=0.804). These results demonstrated that combined heating and electrical stimulation could be an effective method to increase endothelial vasodilator function.Support or Funding InformationThis study was supported in part by Grant‐in‐Aid for Scientific Research from the Japanese Ministry of Education, Science, Sports, and Culture (Grant No. 25750208, 16K16432)