The effects of repeated occlusion measurement on blood pressure and pulse rate

We examined the effects of repeated occlusion measurement on blood pressure and pulse rate during rest and during mental arithmetic stress. Participants performed two rest-and-task sequences. We took automated blood pressure readings during each minute of one rest-and-task sequence (i.e. all-minutes measurement strategy), and during every other minute for the other sequence (i.e. odd-minutes measurement strategy). Each rest-and-task period was 5 min long and we counterbalanced the two rest-and-task sequences for order. Overall, baselines, task levels and reactivity scores were highly similar across the two measurement strategies. We did, however, find small but reliable measurement strategy effects that interacted with task novelty, particularly for DBP. Specifically, DBP levels and reactivity were lower during the all-minutes measurement strategy compared to the odd-minutes strategy, particularly during the second of two repeated tasks. We observed a similar trend for systolic blood pressure, but did not for mean arterial pressure or pulse rate. Our significant effects were small, however, and they should not overshadow the high degree of similarity of results produced by the two measurement strategies.