ABC | Volume 115, Nº1, July 2020

Original Article Perrier-Melo et al. Post-Exercise Hypotension: Interval Vs. Continuous Arq Bras Cardiol. 2020; 115(1):5-14 Figure 3 - Funnel plot of the comparison of interval exercise (IE) vs. continuous exercise (CE) on blood pressure (BP) women, Costa et al. 30 found that there was a reduction in peripheral vascular resistance 60 minutes after IE, when compared to the control session, which did not occur after CE. Considered together, IE seems to induce a greater reduction in peripheral vascular resistance post-exercise, when compared to CE. It is important to emphasize that the studies that compared the hemodynamic determinants of PEH between IE and CE are few and involve different populations, which makes it difficult to understand the possible differences between these protocols. From a clinical point of view, a chronic reduction of 2 mmHg in systolic BP reduces the risk of mortality from stroke by 6% and coronary artery disease by 4%, while a reduction of 5 mmHg decreases 14% and 9% of the risk, respectively. 15 Ameta-analysis showed that the chronic antihypertensive effect of IE and CE is similar in individuals with prehypertension and hypertension, both on systolic (-6.3 vs . -5.8 mmHg) and diastolic BP (-3.8 vs . -3.5mmHg) at rest. 19 Regarding the acute antihypertensive effect of exercise, the present review suggests the superiority of IE over CE for both systolic (~ 3 mmHg) and diastolic (~ 1.3 mmHg) BP. However, it is important to note that this effect was observed between 45-60 minutes after the exercise. Therefore, physical exercisemust be performed regularly so that the chronic benefits can be attained. The findings of this study demonstrated that a single session of aerobic exercise is capable of promoting PEH in adults, regardless of the performed stimulus (CE or IE). The magnitude of the PEHwas associated to the intensity and interval nature of the exercise, so that the IE generated a greater PEH. However, it is important to emphasize that there are different forms of IE prescription, which makes it impossible to determine a protocol that maximizes PEH. Despite the new and interesting results, this systematic review has some limitations: i) only four databases were searched for study inclusion; ii) few studies were included in this review; iii) the included studies involved a small number of participants (between 10 and 30 individuals); iv) different BP measurement methods were used in the studies; v) food and water intake control, level of physical activity and other confounding factors were seldom reported in the studies; vi) short post-exercise BP monitoring time, which makes it difficult to understand the duration of PEH between protocols. Conclusions This systematic review and meta-analysis of crossover studies suggests that IE induces a PEH of greater magnitude compared to CE, between 45-60 minutes post-exercise in adults, both in systolic (~3 mmHg) and diastolic BP (~1.3 mmHg). However, the clinical importance of these findings should be considered with caution. Future studies comparing the acute effect of IE and CE on ambulatorial BP are required in order to clarify whether, in fact, the difference between these types of exercises has clinical importance regarding acute BP control, both in wakefulness and in sleep. 12