Influence of population and exercise protocol characteristics on hemodynamic determinants of post-aerobic exercise hypotension

Blood pressure pattern following a combined exercise session in hypertensive older women

Abstract Objective: The aim of the present study was to verify the behavior of hemodynamic variables in hypertensive older women following a combined exercise session and to identify the intensity of effort achieved in this session. Method: The study included 14 hypertensive older women (72.0±6.7 years old) who regularly practiced physical activities. The participants underwent a one-hour combined exercise session performed in a group, with intensity of effort monitored by accelerometry (Actigraph, model GT3X+). The hemodynamic parameters (systolic blood pressure, diastolic blood pressure, heart rate, stroke volume, cardiac output and peripheral vascular resistance) were individually measured by finger photoplethysmography (Finometer) before and after (60 min) the exercise session. Results: The sessions consisted predominantly of low-light intensity activities (60%) and 20% of class time was spent on sedentary behavior. None of the evaluated variables exhibited changes when the pre and post-exercise values were compared (p>0.05). Systolic blood pressure behavior correlated positively with time spent in sedentary behavior (r=0.541; p=0.045). Conclusion: The combined exercise sessions, as conducted, did not generate post-exercise hypotension. In addition, the time spent in typically sedentary activities during the classes positively correlated with changes in blood pressure, suggesting that combined exercise programs, applied in the form of collective aerobic exercises, should be composed of higher intensity activities.

Acute blood pressure responses after different isometric handgrip protocols in hypertensive patients

OBJECTIVE

The present study analyzed blood pressure responses after a single session of isometric handgrip exercise performed with different volumes and intensities by patients with hypertension.

METHODS

This randomized crossover trial submitted 12 hypertensive patients (58±5 years old) to four isometric handgrip exercise sessions in a random order: 4 x 2 min at 30% of the maximal voluntary contraction (S30%); 4 x 2 min at 50% of the maximal voluntary contraction (S50%2min); 4 x 3 min at 30% of the maximal voluntary contraction (S30%3min); and a control session. The systolic and diastolic blood pressure, heart rate, and rate-pressure product were measured pre- and post-exercise (30th min).

RESULTS

No significant changes were observed in cardiovascular variables after any session (p>0.05 for all comparisons). Similarly, individual analyses revealed heterogeneity in the responses, including increases in blood pressure observed in some sessions. Patients with reduced blood pressure after an isometric handgrip exercise session exhibited a higher body mass index, diastolic blood pressure and heart rate (p<0.05). They also tended to be younger (p=0.07).

CONCLUSION

Isometric handgrip exercise performed with different intensities and volumes did not reduce the blood pressure of hypertensive patients.

Multicomponent Exercise Improves Physical Functioning but Not Cognition and Hemodynamic Parameters in Elderly Osteoarthritis Patients Regardless of Hypertension

The present study aimed to investigate the impact of a 6-month multicomponent exercise program (MCEP) on physical function, cognition, and hemodynamic parameters of elderly normotensive (NTS) and hypertensive (HTS) osteoarthritis patients. A total of 99 elderly osteoarthritis patients (44 NTS and 55 HTS) were recruited and submitted to functional, cognitive, and hemodynamic evaluations before and after six months of a MCEP. The program of exercise was performed twice a week at moderate intensity. The physical exercises aggregated functional and walking exercises. Results indicate that 6 months of MCEP were able to improve one-leg stand and mobility (walking speeds) of osteoarthritis patients regardless of hypertension. On the other hand, cognitive and hemodynamic parameters were not altered after the MCEP. The findings of the present study demonstrate that 6 months of MCEP were able to improve the physical functioning (i.e., usual and maximal walking speed and balance) of osteoarthritis patients regardless of hypertensive condition.

Pathophysiology of Noncardiac Syncope in Athletes

The most frequent cause of syncope in young athletes is noncardiac etiology. The mechanism of noncardiac syncope (NCS) in young athletes is neurally-mediated (reflex). NCS in athletes usually occurs either as orthostasis-induced, due to a gravity-mediated reduced venous return to the heart, or in the context of exercise. Exercise-related NCS typically occurs after the cessation of an exercise bout, while syncope occurring during exercise is highly indicative of the existence of a cardiac disorder. Postexercise NCS appears to result from hypotension due to impaired postexercise vasoconstriction, as well as from hypocapnia. The mechanisms of postexercise hypotension can be divided into obligatory (which are always present and include sympathoinhibition, histaminergic vasodilation, and downregulation of cardiovagal baroreflex) and situational (which include dehydration, hyperthermia and gravitational stress). Regarding postexercise hypocapnia, both hyperventilation during recovery from exercise and orthostasis-induced hypocapnia when recovery occurs in an upright posture can produce postexercise cerebral vasoconstriction. Athletes have been shown to exhibit differential orthostatic responses compared with nonathletes, involving augmented stroke volume and increased peripheral vasodilation in the former, with possibly lower propensity to orthostatic intolerance.

Multicomponent exercise decreases blood pressure, heart rate and double product in normotensive and hypertensive older patients with high blood pressure

OBJECTIVE

The present study aimed to investigate the effects of a 6-month multicomponent exercise program on blood pressure, heart rate, and double product of uncontrolled and controlled normotensive and hypertensive older patients.

METHODS

The study included 183 subjects, 97 normotensives, of which 53 were controlled normotensives (CNS), and 44 uncontrolled normotensives (UNS), as well as 86 hypertensives, of which 43 were controlled hypertensives (CHS), and 43 uncontrolled hypertensives (UHS). Volunteers were recruited and blood pressure and heart rate measurements were made before and after a 6-month multicomponent exercise program. The program of physical exercise was performed twice a week for 26 weeks. The physical exercises program was based on functional and walking exercises. Exercise sessions were performed at moderate intensity.

RESULTS

The results indicated that UHS showed a marked decrease in systolic (-8.0mmHg), diastolic (-11.1mmHg), mean (-10.1mmHg), and pulse pressures, heart rate (-6.8bpm), and double product (-1640bpmmmHg), when compared to baseline. Similarly, diastolic (-5.5mmHg) and mean arterial (-4.8mmHg) pressures were significantly decreased in UNS. Concomitantly, significant changes could be observed in the body mass index (-0.9kg/m²; -1.5kg/m²) and waist circumference (-3.3cm; only UHS) of UNS and UHS, which may be associated with the changes observed in blood pressure.

CONCLUSIONS

In conclusion, the data of the present study indicate that a 6-month multicomponent exercise program may lead to significant reductions in blood pressure, heart rate, and double product of normotensive and hypertensive patients with high blood pressure values.

Androgenic-anabolic steroids inhibited post-exercise hypotension: a case control study

BACKGROUND

There is evidence of hypertensive effects caused by anabolic androgenic steroids (AAS). A single exercise session promotes the acute reduction of blood pressure, but the effects of AAS on this phenomenon are unknown.

OBJECTIVES

To investigate the post-exercise blood pressure response in androgenic-anabolic steroid users.

METHODS

Thirteen AAS users (23.9±4.3 years old) and sixteen controls (22.1±4.5 years old) performed a session of aerobic exercise. Heart rate and blood pressure were assessed before exercise and during a 60min post-exercise resting period. Repeated ANOVA measures were used to determine differences between the groups.

RESULTS

While the control group had a significant reduction in post-exercise systolic blood pressure of up to 13.9±11.6mmHg at 40min, this phenomenon was limited among AAS users who reached a maximum of 6.2±11.5mmHg at 60min. The between groups comparison revealed significant higher post-exercise hypotension (PEH) for the control group at 30min (-12.9±14.1mmHg versus -2.9±7.6mmHg), 40min (-13.9±11.6mmHg versus -2.5±8.3mmHg), 50min (-13.9±13.9mmHg versus -5.0±7.9mmHg) and 60min (-12.5±12.8mmHg versus -6.2±11.5mmHg). There was no significant diastolic PEH in any of the groups.

CONCLUSIONS

This study demonstrated impaired systolic post-exercise hypotension as a new adverse effect of AAS usage.

Low blood pressure is sustained during subsequent activities of daily living performed after power training in older women

The present study aimed to examine the effects of a prior session of power training on blood pressure values during tasks that mimic the activities of daily living in hypertensive and normotensive older women. A randomized crossover experimental design was used for this study. Eleven older women (age, 66.1±1.2 years; body mass index, 26.7±4.8 kg/m²; systolic blood pressure, 133.9±23.4 mmHg) were recruited to participate. Volunteers were randomly underwent to a single session of physical exercise equalized by training volume, characterized by 3 sets of 8–10 repetitions in 8 different exercises. However, Power training session was performed at a higher intensity (moderate) than Sham session (rest/very, very easy ). Immediately after the end of the exercise session, subjects were assigned to perform five tasks that mimic the activities of daily living. Hemodynamic parameters were recorded before and immediately after the session of physical exercise, as well as in the end of each of the tasks. Results demonstrated significant elevations in systolic blood pressure and pulse pressure values during the performance of the tasks after the Sham session. However, values were not altered in the power training session. Data of the present study indicate that an acute session of power training can maintain blood pressure values lower during the subsequent performance of tasks that mimic activities of daily living in older women.

Effects of concurrent and aerobic exercises on postexercise hypotension in elderly hypertensive men

Despite the fact that simultaneous performance of resistance and aerobic exercises (i.e., concurrent exercise) has become a standard exercise prescription for the elderly, no information is available on its effects on post-exercise hypotension (PEH) in elderly men with hypertension.

PURPOSE

To compare the effects of different types of exercise on PEH in elderly men with hypertension.

METHODS

Twenty elderly men with essential hypertension participated in three crossover interventions, in random order, and on separate days: a non-exercise control session at seated rest, aerobic exercise performed for 45min, and 45min of concurrent resistance and aerobic exercise consisted of 4 sets of 8 repetitions at 70% 1RM of resistance exercise followed by aerobic exercise on treadmill. After each session, blood pressure (BP) was measured continuously for 1h in the laboratory and for 24h under ambulatory conditions.

RESULTS

During the first hour in laboratory, diastolic BP was lower after aerobic (-5mmHg) and concurrent exercise (-6mmHg) in comparison with Control. Day-time diastolic BP was significantly lower after aerobic exercise (-7mmHg) when compared to the control. No significant differences were found among the three experimental sessions for night-time and 24-hour diastolic BP, as well as day-time, night-time and 24-hour systolic BP.

CONCLUSION

Concurrent exercise produced acute PEH similar to aerobic exercise but such effect did not last as long as aerobic exercise in elderly patients with essential hypertension.

Cardiovascular responses during resistance exercise after an aerobic session

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Diastolic and mean BP were higher during resistance exercise after aerobic exercise.

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Peak heart rate values were higher during resistance exercise after aerobic exercise.

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Aerobic exercise before resistance exercise promoted higher cardiovascular work.

Objective

To analyze the influence of previous aerobic exercise on cardiovascular responses during resistance exercise.

Methods

This is a crossover observational study. The sample included 19 normotensive men aged between 19 and 39 years. Subjects performed two experimental sessions in random order: resistance exercise (R: three sets of knee extension exercises with 40% of one repetition maximum) and aerobic exercise + resistance exercise (A + R: 30 min of aerobic exercise followed by R protocol). In both sessions, blood pressure (BP) and heart rate were monitored beat-by-beat by finger photoplethysmography.

Results

After aerobic exercise in the A + R session, there was a maintenance of systolic BP −2 (95% CI: −6; 2) mmHg (P = 0.35), diastolic 1 (95% CI: −2; 5) mmHg (P = 0.40) and mean BP 0 (95% CI: −4; 4) mmHg (P = 0.91) and an increase in heart rate 11 (95% CI: 7; 16) bpm (P < 0.001). Diastolic and mean BP increased and peak heart rate was higher during resistance exercise in the A + R session compared to the R session. Differences between sessions: diastolic BP 7 (95% CI: 2; 12) mmHg (P = 0.03); mean BP 8 (95% CI: 2; 13) mmHg (P = 0.05); and peak heart rate 18 (95% CI: 13; 23) bpm (P < 0.001). The increases in systolic BP during resistance exercise were similar between sessions 16 (95% CI: 6; 26) mmHg (P = 0.43).

Conclusion

Aerobic exercise before resistance exercise increased diastolic and mean BP and heart rate. However, due to the sample size of 19 individuals, the results must be interpreted with caution.

Gender Differences in Heart Rate Variability Among Individuals Undergoing Regular Resistance Training Preliminary observations

OBJECTIVES

Frequency-domain analysis of heart rate variability (HRV) is an effective tool to evaluate autonomic balance. This study aimed to investigate gender differences in HRV among individuals undergoing regular resistance training.

METHODS

This preliminary cross-sectional study was conducted from April to September 2016 in João Pessoa, Paraíba, Brazil. The low-frequency (LF), high-frequency (HF) and LF/HF ratio components of HRV spectral analysis were analysed among 22 men and 27 women undergoing regular resistance training.

RESULTS

Among the male participants, the LF component was significantly increased compared to females in both the supine (1,171 ± 192 versus 545 ± 74 ms²; P = 0.0067) and upright (1,824 ± 260 versus 738 ± 133; P = 0.0011) positions. The LF/HF ratio was also significantly increased in both positions among male participants (P <0.0500 each).

CONCLUSION

These preliminary data suggest a possible gender difference in the HRV of individuals undergoing resistance training.

Fractionated Concurrent Exercise throughout the Day Does Not Promote Acute Blood Pressure Benefits in Hypertensive Middle-aged Women

Hypertension is a chronic disease that affects about 30% of the world’s population, and the physical exercise plays an important role on its non-pharmacological treatment. Anywise, the dose–response of physical exercise fractionation throughout the day demands more investigation, allowing new exercise prescription possibilities. Therefore, this study aimed to analyze the acute blood pressure (BP) kinetics after 1 h of exercises and the BP reactivity after different concurrent exercise (CE) sessions and its fractioning of hypertensive middle-aged women. In this way, 11 hypertensive women voluntarily underwent three experimental sessions and one control day [control session (CS)]. In the morning session (MS) and night session (NS), the exercise was fully realized in the morning and evening, respectively. For the fractionized session (FS), 50% of the volume was applied in the morning and the remaining 50% during the evening. The MS provided the greatest moments (p ≤ 0.05) of post-exercise hypotension (PEH) for systolic BP (SBP) and highest reduction of BP reactivity for SBP (~44%) and diastolic BP (DBP) (~59%) compared to CS (p ≤ 0.05). The findings of the present study have shown that MS is effective for PEH to SBP, as well as it promotes high quality of attenuation for BP reactivity, greater than the other sessions.

The cardiovascular system after exercise

Recovery from exercise refers to the time period between the end of a bout of exercise and the subsequent return to a resting or recovered state. It also refers to specific physiological processes or states occurring after exercise that are distinct from the physiology of either the exercising or the resting states. In this context, recovery of the cardiovascular system after exercise occurs across a period of minutes to hours, during which many characteristics of the system, even how it is controlled, change over time. Some of these changes may be necessary for long-term adaptation to exercise training, yet some can lead to cardiovascular instability during recovery. Furthermore, some of these changes may provide insight into when the cardiovascular system has recovered from prior training and is physiologically ready for additional training stress. This review focuses on the most consistently observed hemodynamic adjustments and the underlying causes that drive cardiovascular recovery and will highlight how they differ following resistance and aerobic exercise. Primary emphasis will be placed on the hypotensive effect of aerobic and resistance exercise and associated mechanisms that have clinical relevance, but if left unchecked, can progress to symptomatic hypotension and syncope. Finally, we focus on the practical application of this information to strategies to maximize the benefits of cardiovascular recovery, or minimize the vulnerabilities of this state. We will explore appropriate field measures, and discuss to what extent these can guide an athlete's training.

Differential Post-Exercise Blood Pressure Responses between Blacks and Caucasians

Post-exercise hypotension (PEH) is widely observed in Caucasians (CA) and is associated with histamine receptors 1- and 2- (H1R and H2R) mediated post-exercise vasodilation. However, it appears that blacks (BL) may not exhibit PEH following aerobic exercise. Hence, this study sought to determine the extent to which BL develop PEH, and the contribution of histamine receptors to PEH (or lack thereof) in this population. Forty-nine (22 BL, 27 CA) young and healthy subjects completed the study. Subjects were randomly assigned to take either a combined H1R and H2R antagonist (fexofenadine and ranitidine) or a control placebo. Supine blood pressure (BP), cardiac output and peripheral vascular resistance measurements were obtained at baseline, as well as at 30 min, 60 min and 90 min after 45 min of treadmill exercise at 70% heart rate reserve. Exercise increased diastolic BP in young BL but not in CA. Post-exercise diastolic BP was also elevated in BL after exercise with histamine receptor blockade. Moreover, H1R and H2R blockade elicited differential responses in stroke volume between BL and CA at rest, and the difference remained following exercise. Our findings show differential BP responses following exercise in BL and CA, and a potential role of histamine receptors in mediating basal and post-exercise stroke volume in BL. The heightened BP and vascular responses to exercise stimulus is consistent with the greater CVD risk in BL.

Acute Effects of T'ai Chi Chuan Exercise on Blood Pressure and Heart Rate in Peripheral Artery Disease Patients

OBJECTIVE

To investigate the acute effect of a t'ai chi chuan session on blood pressure and heart rate in patients with peripheral artery disease (PAD).

DESIGN

Randomized crossover intervention study.

SETTING

Outpatient therapy center.

PARTICIPANTS

Seven patients with PAD, aged 50-79 years, not using β-blockers, calcium-channel blockers, or nondihidropiridinic vasodilators.

INTERVENTION

T'ai chi chuan and control session (both sessions lasted 40 minutes).

OUTCOME MEASURES

Systolic and diastolic blood pressure and heart rate, which were evaluated before and after the intervention (10, 30, and 50 minutes).

RESULTS

T'ai chi chuan exercise acutely decreased systolic blood pressure at 30 minutes after exercise (p = 0.042) and increased diastolic blood pressure at 50 minutes after exercise (p = 0.041). Heart rate did not change after t'ai chi chuan exercise.

CONCLUSION

T'ai chi chuan acutely decreases systolic blood pressure in patients with PAD.

Post-Exercise Hypotension and Its Mechanisms Differ after Morning and Evening Exercise: A Randomized Crossover Study

Post-exercise hypotension (PEH), calculated by the difference between post and pre-exercise values, it is greater after exercise performed in the evening than the morning. However, the hypotensive effect of morning exercise may be masked by the morning circadian increase in blood pressure. This study investigated PEH and its hemodynamic and autonomic mechanisms after sessions of aerobic exercise performed in the morning and evening, controlling for responses observed after control sessions performed at the same times of day. Sixteen pre-hypertensive men underwent four sessions (random order): two conducted in the morning (7:30am) and two in the evening (5pm). At each time of day, subjects underwent an exercise (cycling, 45 min, 50%VO₂peak) and a control (sitting rest) session. Measurements were taken pre- and post-interventions in all the sessions. The net effects of exercise were calculated for each time of day by [(post-pre exercise)-(post-pre control)] and were compared by paired t-test (P<0.05). Exercise hypotensive net effects (e.g., decreasing systolic, diastolic and mean blood pressure) occurred at both times of day, but systolic blood pressure reductions were greater after morning exercise (-7±3 vs. -3±4 mmHg, P<0.05). Exercise decreased cardiac output only in the morning (-460±771 ml/min, P<0.05), while it decreased stroke volume similarly at both times of day and increased heart rate less in the morning than in the evening (+7±5 vs. +10±5 bpm, P<0.05). Only evening exercise increased sympathovagal balance (+1.5±1.6, P<0.05) and calf blood flow responses to reactive hyperemia (+120±179 vs. -70±188 U, P<0.05). In conclusion, PEH occurs after exercise conducted at both times of day, but the systolic hypotensive effect is greater after morning exercise when circadian variations are considered. This greater effect is accompanied by a reduction of cardiac output due to a smaller increase in heart rate and cardiac sympathovagal balance.