IHG training reduces arterial blood pressure (ABP), particularly in hypertensive subjects and was shown to enhance reactive hyperaemia in the trained arm (1, 2). We hypothesised that IHG training may have remote effects on endothelial dilator function. Since the prevalence of cardiovascular disease (CVD) is greater in White Europeans (WEs) and South Asians (SAs) men, we tested whether IHG training would similarly affect reactive and exercise hyperaemia in the untrained arm of young SA and WE men. Experiments were performed on 10 recreationally active young (18-25 years) WE and 10 SA men (1st or 2nd generation UK residents originating from the Indian subcontinent. IHG training comprised 4x3min contractions at 30% Maximum voluntary contraction (MVC) at 5min intervals, 4 days/week for 4 weeks with the dominant arm. Forearm blood flow (FBF) was recorded by venous occlusion plethysmography at rest and at intervals after 3-min rhythmic handgrip contractions at 60%MVC (exercise hyperemia) and 3-min arterial occlusion (reactive hyperaemia) before and after training. As expected, MVC was increased after IHG training in the trained arm (WEs: 29.0±1.3, vs 33.5±1.5§Kg; SAs: 27.6±1.6, vs 32.6±1.0§, §: P< 0.01, paired t-test), but not in the untrained arm (WEs: 27.0±0.9 vs 27.1±0.9Kg; SAs: 26.1± 0.9 vs 26.8±0.9Kg). Resting arterial blood pressure was not different between WEs and SAs and not changed by IHG training: WEs 124±1.8/70±1.7 vs 125±1.8/72±1.6 mmHg; SAs: 116.33±1.76/64.44±1.13 vs 115.90±1.65/74.0±1.75 mmHg. FBF in the untrained arm was also not different between WEs and SAs and not changed by IHG training: WEs 4.8±0.9 vs 6.6±0.8; SAs 5.3±1.0 vs 6.8±1.1 ml.100ml-1.min-1. However, peak exercise hyperaemia in the untrained arm was increased by IHG training, from 77.8±9.4 to 101.1±2.9* ml.100ml-1.min-1 in WEs and from 86.1±3.0 to 98.2±3.3* ml.100ml-1.min-1 in SAs (*: P< 0.01 RMANOVA). Furthermore, reactive hyperaemia increased from 41.4±1.9 to 50.8±2.0* ml.100ml-1.min-1 in the untrained arm of WEs and from 45.2±2.1 to 49.8±2.1 ml.100ml-1.min-1 in SAs. These results indicate that in healthy young WE and SA men, IHG training of one arm for 4 weeks not only improves peak muscle power in the trained arm but induces a concomitant increase in exercise and reactive hyperaemia in the untrained trained arm in the absence of a change in muscle power. The mechanisms underlying these effects are not yet clear, but we propose IHG training does have remote, beneficial effects on endothelial dilator function, which are mediated by increased shear stress. These effects may be more pronounced in young WE than SA men, reflecting the latter’s predisposition to CVD.