Does combining elastic and weight resistance acutely protect against the impairment of flow-mediated dilatation in untrained men?

Background: The evidence that the combination of elastic and weight resistance training acutely affects or improves resultant responses to conduit artery function is anecdotal. The aim of this study was to examine brachial artery flow-mediated vasodilation (FMD) before and after acute exercise when performed at 3 conditions of resistance. Methods: Fourteen healthy, untrained (inactive) male participants (Mean age ± SD: 20.6 ± 0.5 years) completed 3 sets of 15 repetitions of the single-arm curl exercise. Testing was executed on 3 separate days as follows: day 1 with a dumbbell alone (DA), day 2 with elastic tubing alone (EA), and day 3 with a dumbbell with elastic tubing (DWE). Testing was executed in random order. Within the DWE condition, the resistance provided by the elastic tubing was equivalent to 20% of the subjects’ 15 repetition maximum (RM). A one-way repeated measures analysis of variance was employed to evaluate different loading conditions on FMD. Results: The results demonstrated that FMD was significantly greater during DWE than during EA, DA, and at baseline FMD (p < 0.05). Moreover, brachial FMD improved from baseline in the DWE condition (to 21.5 ± 7.3%; p < 0.05) but not significantly in the EA condition (to 14.3 ± 4.4%; p ≥ 0.05), and actually decreased significantly in the DA condition (to 8.3 ± 3.1%; p < 0.05). Conclusion: DWE exhibits notable efficacy for improving endothelial function in inactive men during the single arm curl exercise.