Effect of very low-intensity resistance exercise on aortic-brachial blood pressure disparity in young men.

Background: Resistance exercise is accompanied by pronounced elevations in pulse pressure during and following exercise. Whether an increase in aortic pulse pressure during resistance exercise is mitigated by a reduction in exercise intensity remains uncertain. We examined the effects of resistance exercise at 10% and 40% one-repetition maximum on aortic pulse pressure.

Methods: Sixteen participants performed resistance exercise to exhaustion at 10% and 40% of one-repetition maximum, along with a sham control, on separate days in a randomized controlled crossover design. Brachial pressure waveforms were recorded using the SphygmoCor XCEL device to estimate the aortic pulse pressure, forward and backward pressure amplitudes, and augmentation index both prior to resistance exercise or equivalent seated rest and at 3-min post-intervention.

Results: An increase in aortic pulse pressure following resistance exercise was smaller at 10% one-repetition maximum compared to 40% one-repetition maximum (p = 0.02), whereas the rise in brachial pulse pressure did not differ between these intensities. The increases in backward pressure amplitude and augmentation index were smaller at 10% one-repetition maximum (both, p<0.05), while forward pressure amplitude remained consistent across intensities.

Conclusion: These findings highlight disparities in post-exercise pulse pressure responses between the aortic and brachial arteries, which can be attributed to differences in backward pressure amplitude. The beneficial effects of 10% one-repetition maximum resistance exercise became evident when assessing aortic pressure waveforms. To attenuate excessive increases in aortic pulsatile pressure stress during and after resistance exercise, 10% one-repetition maximum may serve as a relatively low-risk intensity.