Acute effect of interval step exercise versus continuous walk exercise on cardiovascular parameters in hypertensive postmenopausal women: A clinical, controlled, and randomized study.

Aiming the prevention and treatment of hypertension, regular physical exercise has become important to reduce blood pressure. The present experiment compared the effect of interval step exercise with continuous walking exercise on cardiovascular parameters of post-menopausal hypertensive women. The volunteers were submitted to three experimental sessions: control (CO), interval exercise (IE) and continuous exercise (CE), in randomized order. The sessions lasted 120 min and during this period, resting blood pressure was evaluated after 10min of siting rest before exercise, and 30, 40 and 60min of siting rest position after exercise. Heart rate variability (HRV) were estimated at rest before exercise and 30min after exercise. Blood pressure reactivity (BPR) to the Stroop Color-Word test was measured at rest before exercise and 60min after exercise. Twelve women finished the study (59 ± 4 years and BMI of 29.78 ± 4.10 kg/m2). The One way ANOVA showed that systolic blood pressure (SBP) area under the curve over time were lower (p = 0.014) in both exercise sessions comparing with control session. The Generalized estimation equations (GEE) showed that SDNN and RMSSD indices of HRV decreases (p < 0.001) in both exercises session as well, comparing with CO. Maximal SBP during Stroop test were lower after both IE and CE exercises session comparing with CO session. We conclude that interval step exercise can reduce blood pressure responses and improve HRV acutely after its performance and these responses are similar to continuous walking exercise.

Beetroot juice intake with different amounts of nitrate does not change aerobic exercise-mediated responses in heart rate variability in hypertensive postmenopausal women: A randomized, crossover and double-blind study.

OBJECTIVES: To compare the acute effects of a single dose of beetroot juice (BJ) with different concentrations of nitrate (NO3 -) on heart rate variability (HRV) in postmenopausal hypertensive women. METHODS: Thirteen hypertensive postmenopausal women (58.1 ± 4.6 years of age and 27 ± 4 kg/m2 of BMI) completed the protocol that consisted of three visits with different beverage intakes in a randomized and crossover design. The three beverages were BJ with a high content of nitrate (high-NO3 -), BJ with a low content of nitrate (low-NO3 -), and an orange flavored non-caloric drink (OFD). Heart rate (HR) were evaluated during 20 min after sitting rest at 7:20 a.m. (baseline), after they drank one of the drinks, and remained at sitting rest for 120 min and then performed 40 min of aerobic exercise at 65-70% of the HR reserve on a treadmill. HR was recorded for 90 min after exercise for time, frequency, and non-linear domains of HRV index analysis. RESULTS: Two-way ANOVA showed that there were no interaction effects (time∗sessions) in any of the HRV indexes after exercise in all three sessions. HRV indexes increased after exercise (p = <0.05) similarly in all three sessions when compared with the baseline time point. CONCLUSION: Therefore, a single dose of BJ, independent of NO3 - content, does not change aerobic exercise-mediated responses in HRV indexes in hypertensive postmenopausal women.

Effect of combined exercise training on heart rate variability in normotensive and hypertensive postmenopausal women

Abstract Aim: This study aimed to verify and compare the effects of 10 weeks of combined exercise training on the heart rate variability of normotensive (NT) and hypertensive (HT) postmenopausal women. Methods: This is a quasi-experimental controlled clinical trial. Therefore, 14 HT and 12 NT postmenopausal women completed 10 weeks of combined exercise training. The exercise protocol consisted of 45 min of exercise, performed 3 times a week, consisting of 5 min of warm-up, 20 min of resistance exercise, and 20 min of aerobic exercise. Heart rate variability assessments were performed before and after the end of physical training. Results: Heart rate variability was assessed pre- and post-training periods. Mean RR (δNT = 95 ± 88; δHT = 38 ± 127), SDNN (δNT = 9 ± 13; δHT = 3 ± 14), RMSSD (δNT = 10 ± 12; δHT = 2 ± 18), SD1 (δNT = 7 ± 8; δHT = 1 ± 13), and SD2 (δNT = 10 ± 18; δHT = 4 ± 17) showed improvements after the intervention (time effects p < 0.05). No parameters presented group or interaction effects (p ≥ 0.05). Conclusion: In summary, 10 weeks of combined exercise training improved heart rate variability parameters similarly in both NT and HT postmenopausal women. Therefore, combined exercise training may be used to improve autonomic modulation of the heart rate of postmenopausal women, regardless of the presence of hypertension.

A Single Dose of Beetroot Juice Does Not Change Blood Pressure Response Mediated by Acute Aerobic Exercise in Hypertensive Postmenopausal Women.

OBJECTIVE: To verify if acute intake of beetroot juice potentiates post-exercise hypotension (PEH) in hypertensive postmenopausal women. METHODS: Thirteen hypertensive postmenopausal women (58.1 ± 4.62 years and 27.4 ± 4.25 kg/m²) were recruited to participate in three experimental sessions, taking three different beverages: Beetroot juice (BJ), placebo nitrate-depleted BJ (PLA), and orange flavored non-caloric drink (OFD). The participants performed moderate aerobic exercise training on a treadmill, at 65-70% of heart rate reserve (HRR), for 40 min. After an overnight fast, the protocol started at 07h when the first resting blood pressure (BP) was measured. The beverage was ingested at 07h30 and BP was monitored until the exercise training started, at 09h30. After the end of the exercise session, BP was measured every 15 min over a 90-min period. Saliva samples were collected at rest, immediately before and after exercise, and 90 min after exercise for nitrite (NO2-) analysis. RESULTS: There was an increase in salivary NO2- with BJ intake when compared to OFD and PLA. A slight increase in salivary NO2- was observed with PLA when compared to OFD (p < 0.05), however, PLA resulted in lower salivary NO2- when compared to BJ (p < 0.001). There were no changes in salivary NO2- with the OFD. Systolic and diastolic BP decreased (p < 0.001) on all post exercise time points after all interventions, with no difference between the three beverages. CONCLUSION: Acute BJ intake does not change PEH responses in hypertensive postmenopausal women, even though there is an increase in salivary NO2-.