Postexercise hypotension: central mechanisms

Effect of Acute Dietary Nitrate Supplementation on the Post-Exercise Ambulatory Blood Pressure in Obese Males: A Randomized, Controlled, Crossover Trial

This study aimed to verify the effect of beetroot juice on post-exercise ambulatory blood pressure (BP) in obese individuals. Fourteen non-hypertensive obese males were randomly assigned to three experimental sessions: 1) Beetroot juice with exercise (BJE, 200ml with ≈ 800mg nitrate and 40 minutes of moderate-intensity aerobic exercise at an intensity of 50% of the heart rate reserve), 2) fruit soda with exercise (FSE, 200ml of a low-nitrate drink and the same exercise session) and 3) control (CON, 200ml of water, an insignificant nitrate drink without exercise). The concentration of total nitrites and nitrates in plasma (NOx) after the drinks and the 24-hour ambulatory BP were evaluated. A two-way (condition vs. time) ANOVA for repeated measures, with a Bonferroni post hoc was used to analyze variables. The plasma NOx concentration increased significantly after ingestion of beetroot juice (from 9.9 ± 8.4 μM to 47.0 ± 16.9 μM, p < 0.001) and remained elevated until 1 hour post-intervention (54.7 ± 10.1 μM, p < 0.001), while it did not change in FSE and CON groups. The BJE session decreased ambulatory systolic BP in 5.3 mmHg (IC95%, -10.1 to -0.6, p = 0.025) in the period of 1-6 h after the BJE session compared to the CON session and reduction of 3.8 mmHg (IC95%, -7.5 to -0.007, p = 0.05) compared to the FSE session. No significant changes were observed for ambulatory diastolic BP (p > 0.05). BJE enhanced the reduction of systolic ambulatory BP up to 6 hours following a moderate-intensity aerobic exercise in obese individuals with an elevated cardiovascular risk profile.

Cardiovascular responses to leg muscle loading during head-down tilt at rest and after dynamic exercises

The physiological processes underlying hemodynamic homeostasis can be modulated by muscle activity and gravitational loading. The effects of leg muscle activity on cardiovascular regulation have been observed during orthostatic stress. Here, we evaluated such effects during head-down tilt (HDT). In this posture, the gravitational gradient along the body is different than in upright position, leading to increased central blood volume and reduced venous pooling. We compared the cardiovascular signals obtained with and without leg muscle loading during HDT in healthy human subjects, both at rest and during recovery from leg-press exercises using a robotic device. Further, we compared such cardiovascular responses to those obtained during upright position. Loading leg muscles during HDT at rest led to significantly higher values of arterial blood pressure than without muscle loading, and restored systolic values to those observed during upright posture. Maintaining muscle loading post-exercise altered the short-term cardiovascular responses, but not the values of the signals five minutes after the exercise. These results suggest that leg muscle activity modulates cardiovascular regulation during HDT. This modulation should therefore be considered when interpreting cardiovascular responses to conditions that affect both gravity loading and muscle activity, for example bed rest or microgravity.

Acute Effect of a Single Session of Pilates on Blood Pressure and Cardiac Autonomic Control in Middle-Aged Adults With Hypertension

Rocha, J, Cunha, FA, Cordeiro, R, Monteiro, W, Pescatello, LS, and Farinatti, P. Acute effect of a single session of Pilates on blood pressure and cardiac autonomic control in middle-aged adults with hypertension. J Strength Cond Res 34(1): 114-123, 2020-We investigated the blood pressure (BP) and heart rate variability (HRV) responses to a single session of Pilates among adults with hypertension. Thirteen participants (7 women), aged 44-66 years, underwent Pilates and nonexercise control sessions separated by 48-72 hours in a randomized counterbalanced order. Blood pressure and HRV indices were simultaneously assessed 10 minutes before and 60 minutes after all sessions in the supine position: root mean square of successive differences (rMSSD), percentage of successive normal sinus RR intervals >50 ms (pNN50), SD of all normal sinus RR intervals over 24 hours (SDNN), and low-frequency (LF) and high-frequency (HF) bands. After an acute session of Pilates, the mean values for area under the curve for systolic BP (p = 0.004, corresponding to -7.4 ± 8.2 mm Hg) and mean arterial pressure (p = 0.023, corresponding to -5.3 ± 5.4 mm Hg) were significantly lower compared to the control session. No significant difference was detected for diastolic BP (-4.2 ± 4.7 mm Hg, p = 0.106). Concomitant to BP reduction, significant lowering of parasympathetic HRV indices occurred: RR intervals (-64.1 ± 69.9 ms·min, p = 0.043), rMSSD (-8.3 ± 15.4 ms·min, p = 0.013), pNN50 (-3.6 ± 13%·min, p = 0.028), and total power (-3,089.4 ± 5,938 m·min, p = 0.037). No difference was found for sympathetic markers: SDNN (-17.7 ± 34.6 ms·min, p = 0.100), LF (-5.2 ± 21,6 n.u.·min, p = 0.417), and LF:HF ratio (-0.3 ± 5.2 ratio·min, p = 0.422). In conclusion, a single session of Pilates reduced BP by ∼5-8 mm Hg in adults with hypertension during the first 60 minutes of post-exercise recovery. Acute BP reduction was concomitant to lowered cardiac parasympathetic activity. Our findings are promising for the use of Pilates as an alternative exercise modality to lower BP.

Distinct effects of early-life experience and trait aggression on cardiovascular reactivity and recovery

We previously demonstrated independent effects of early-life experience (ELE) and trait aggression (TA) on resting heart rate (HR) and mean arterial pressure (MAP) in rats. The present study examined the effects of TA and ELE on stress-evoked cardiovascular reactivity and recovery. Pups born to Wistar-Kyoto dams were exposed to daily 180-min periods of maternal separation (MS) during the first two weeks of life, and aggression was assessed in adult offspring using the resident-intruder test. Radiotelemetry was then used to record stress-evoked HR and MAP responses in response to: strobe light, novel environment, intruder rat, or restraint. Maximal HR and MAP responses were quantified as indices of reactivity, and exponential decay curves were fitted to determine decay constants as a measure of recovery. Strobe light was the weakest stressor, evoking the lowest increases in MAP and HR, which were significantly greater in MS-exposed rats irrespective of TA. In contrast, reactivity to and recovery from exposure to a novel environment or an intruder were significantly influenced by TA, but not ELE. TA animals exhibited greater reactivity in both of these paradigms, with either decreased (novel environment) or increased (intruder) recovery. Restraint stress induced the largest changes in HR and MAP with the slowest recovery, and these responses were shaped by a significant ELE x TA interaction. These data indicate that cardiovascular reactivity and recovery are influenced by ELE, TA, or ELE x TA interaction depending on stressor aversiveness as well as its physical and psychological dimensions.

Effects of a highly intensive clean and jerk exercise on blood pressure and arterial stiffness in experienced non-professional weight lifters

PURPOSE

Weight lifting training has gained much popularity in recent years and is frequently used in non-professional and professional settings. However, little is known about the acute effects of a highly intensive weight lifting exercise (clean and jerk) on the hemodynamic reaction.

METHODS

18 non-professional experienced weight lifters were recruited. Hemodynamic parameters were obtained and measured at baseline (T1), after warming up (T2), and after a highly intensive clean and jerk exercise (90-95% of personal best; T3). Further, 15 (T4), and 30 min (T5) post-exercise measurements were conducted. Evaluated parameters were heart rate (HR) (b/min), peripheral and central systolic and diastolic blood pressure (pSysBP, pDiaBP, cSysBP, cDiaBP) (mmHg), pulse wave velocity (PWV) (m/s), and double product (DP).

RESULTS

All hemodynamic values increased from T1 up to T3 with significantly higher values measured at T3 compared to T1 and T2. Values of measured parameters at T3 were as follows: HR: 94.4 ± 15.6 b/min, pSysBP: 147.1 ± 15.9 mmHg, pDiaBP: 87.4 ± 12.2 mmHg, cSysBP: 129.3 ± 13.8 mmHg, cDiaBP: 89.9 ± 12.8 mmHg, and: 5.8 ± 0.5 m/s, DP: 14053 ± 3669. Post-exercise (T4, T5), all values returned to baseline levels.

CONCLUSIONS

Results indicate that a highly intensive weight lifting exercise led to an acute increase of blood pressure and an acute stiffening of the arteries. Yet, increases were moderate and did not reach disproportionately high levels and returned to baseline levels within 15 min post-exercise. Hence, no negative acute effects of a maximum weight lifting exercise on the hemodynamic system are observed.

Comparing the Changes in Blood Pressure After Acute Exposure to Tai Chi and Walking

Hypertension is a major health concern throughout the United States and is a major cause of cardiovascular disease. The purpose of this study was to compare the responses of Tai Chi and walking on measures of central and peripheral cardiac mechanisms when controlling for exercise intensity. Fifteen hypertensive subjects (2 males, 13 females; age = 20.7 ± 3.77 years; body fat = 24.26 ± 10.27%) participated in Tai Chi (TC) and walking (WK) for 30 minutes on non-consecutive days. Central systolic (CSBP) and diastolic blood pressure (CDBP), augmentation index (Alx), pulse pressure (PP), heart rate (HR), and brachial systolic (BSBP) and diastolic blood pressure (BDBP) were measured prior to exercise and following exercise every 10 minutes for a total of 60 minutes in a seated position. There were no significant differences between the two exercise forms. CSBP decreased 10 minutes after exercise in both exercise types (TC = 6.63 ± 3.258 mmHG; WK = 7 ± 4.144 mmHG p < 0.05), and 40 minutes after exercise in both exercise types (TC = 6.07 ± 3.33 mmHG; WK = 8.2 ± 3.15 mmHG, p < 0.05) compared to the initial measurement. BSBP also decreased in both exercise forms following 10 min of rest (TC = 6.99 ± 3.776 mmHG; WK = 8.8 ± 3.20 mmHG p = 0.05), and 40 min (TC = 8.46 ± 3.07 mmHG; WK = 8.87 ± 3.87 mmHG, p < 0.05) when compared to the initial resting measurement. Central aortic pressure exhibits a post exercise hypotensive (PEH) effect similar to that of peripheral blood pressure. Both Tai Chi and walking elicited similar PEH effects on systolic blood pressure in hypertensive individuals.

Continuous and Accumulated Bouts of Cycling Matched by Intensity and Energy Expenditure Elicit Similar Acute Blood Pressure Reductions in Prehypertensive Men

Fonseca, GF, Farinatti, PTV, Midgley, AW, Ferreira, A, de Paula, T, Monteiro, WD, and Cunha, FA. Continuous and accumulated bouts of cycling matched by intensity and energy expenditure elicit similar acute blood pressure reductions in prehypertensive men. J Strength Cond Res 32(3): 857-866, 2018-This study investigated differences in postexercise hypotension (PEH) after continuous vs. accumulated isocaloric bouts of cycling. Ten prehypertensive men, aged 23-34 years, performed 2 bouts of cycling at 75% oxygen uptake reserve, with total energy expenditures of 400 kcal per bout. One exercise bout was performed continuously (CONTIN) and the other as 2 smaller bouts each expending 200 kcal (INTER1 and INTER2). Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), and cardiac autonomic control were monitored in a supine position for 10 minutes before and 60 minutes after each exercise bout, and during a control session. Compared with control, blood pressure was significantly reduced after CONTIN (SBP: [INCREMENT] - 3.4 mm Hg, p < 0.001; MAP: [INCREMENT] - 2.5 mm Hg, p = 0.001), INTER1 (SBP: [INCREMENT] - 2.2 mm Hg, p = 0.045), and INTER2 (SBP: [INCREMENT] - 4.4 mm Hg, p < 0.001; DBP: [INCREMENT] - 2.7 mm Hg, p = 0.045; MAP: [INCREMENT] - 3.3 mm Hg, p = 0.001). The PEH was similar in CONTIN and INTER2, whereas INTER2 elicited greater PEH than INTER1 (SBP and MAP: [INCREMENT] - 2.0 and [INCREMENT] - 1.8 mm Hg, respectively, p ≤ 0.05). Increases in sympathovagal balance from baseline were inversely related to changes in SBP and DBP after CONTIN and INTER2 (r = -0.64 to -0.71; p = 0.021-0.047). These findings indicate that similar amounts of PEH are observed when exercise is performed as a single 400-kcal exercise bout or 2 × 200-kcal bouts and that the exercise recovery pattern of cardiac autonomic activity may be important in eliciting PEH.

Exercise-Induced Modulation of Baroreflex Control of Sympathetic Nerve Activity

Exercise modulates arterial pressure (AP) regulation over various time spans. AP increases at the onset of exercise and this increase is then sustained during exercise. Once exercise is stopped, AP is suppressed for up to an hour afterwards. Prolonged endurance training is associated with dysfunction of the sympathetic regulation of AP in response to posture changes (orthostatic intolerance). Baroreflex control of sympathetic nerve activity (SNA) has been extensively studied to understand the mechanisms underlying exercise-induced changes in AP. We have previously presented entire baroreflex AP-SNA curves during and after exercise, and during central volume expansion, obtained using direct measurements of renal sympathetic nerve activity (RSNA) in conscious animals. In this review, we describe the modulatory effects of exercise on baroreflex control of AP based on these entire AP-RSNA baroreflex curves. We suggest that both acute and chronic exercise can have modulatory effects on the entire baroreflex curve for SNA, and that these effects differ among time periods.

Intermittent versus constant aerobic exercise in middle-aged males: acute effects on arterial stiffness and factors influencing the changes

PURPOSE

Both constant and intermittent acute aerobic exercises have been found to decrease arterial stiffness. However, direct comparisons of these two types of exercise are sparse. It is not known which type of exercise has the greatest effect.

METHODS

We evaluated the haemodynamic responses in 15 males (age 48.5 ± 1.3 years; BMI 27.5 ± 0.8 kg m^-2) following acute constant (CE) and intermittent cycling exercise (IE). Duration and heart rate were matched during both exercises (131.8 ± 3.2 bpm for CE and 132.0 ± 3.1 bpm for IE). Central and peripheral arterial stiffness was assessed through pulse wave velocity (PWV). Plasma concentrations of nitric oxide (NO), atrial natriuretic peptide (ANP), blood lactate, noradrenaline, and adrenaline were measured before and after each exercise.

RESULTS

Central (+ 1.8 ± 7.4 and - 6.5 ± 6.8% for CE and IE) and upper limb PWV (+ 2.7 ± 6.2 and - 8 ± 4.6% for CE and IE) were not significantly altered although a small decrease (small effect size) was observed after IE. However, lower limb PWV significantly decreased after exercises (- 7.3 ± 5.7 and - 15.9 ± 4% after CE and IE), with a larger effect after IE.

CONCLUSIONS

Greater decrease in lower limb PWV occurred after IE despite greater heart rate. This may be due to the higher blood levels of lactate during IE, while NO, ANP, noradrenaline, and adrenaline levels remained not statistically different from CE. These results underlined the importance of lactate in triggering the post-exercise vascular response to exercise, as well as its regional characteristic.

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.

The influence of physical training status on postexercise hypotension in patients with hypertension: a cross-sectional study

BACKGROUND

To date, few studies have analyzed postexercise hypotension (PEH) in hypertensive patients with different levels of physical fitness.

AIM

Therefore, this study aimed to compare PEH in trained and sedentary hypertensive individuals.

METHODS

Fifty-one well-controlled hypertensive patients of both sexes were assigned to a trained group [60.4±9.4 years; resting blood pressure (BP)=126.3±5.4/75.0±6.3 mmHg; VO2peak=27.3±4.6 ml kg/min] and 58 sedentary hypertensive patients of both sexes were assigned to a sedentary group (63.1±8.9 years; resting BP=134.1±4.2/82.9±5.8 mmHg; VO2peak=20.6±5.5 ml/kg/min). In a cross-sectional design, the individuals were randomized to perform an aerobic exercise session (treadmill; 40 min; 55% VO2peak) and a control session on two different days in the morning. After each session, participants wore an ambulatory BP device for 12 h.

RESULTS

Although no significant differences were identified in BP after the control session, after the experimental session, the trained participants presented lower values than the sedentary participants for systolic (124.1±6.3 vs. 133.4±5.2 mmHg, P<0.01) and diastolic BP (73.1±4.4 vs. 85.5±6.4 mmHg, P<0.01) over the course of 12 h monitoring. For the trained participants, significant correlations were also identified (P<0.05) between the VO2peak and systolic (R=-0.68) and diastolic BP (R=-0.61) 12 h monitoring.

CONCLUSION

In conclusion, the training level of hypertensive patients influences PEH.

A Single Session of Low-Volume High-Intensity Interval Exercise Reduces Ambulatory Blood Pressure in Normotensive Men

Dantas, TCB, Farias Junior, LF, Frazão, DT, Silva, PHM, Sousa Junior, AE, Costa, IBB, Ritti-Dias, RM, Forjaz, CLM, Duhamel, TA, and Costa, EC. A single session of low-volume high-intensity interval exercise reduces ambulatory blood pressure in normotensive men. J Strength Cond Res 31(8): 2263-2269, 2017-The magnitude and duration of postexercise hypotension (PEH) may provide valuable information on the efficacy of an exercise approach to blood pressure (BP) control. We investigated the acute effect of a time-efficient high-intensity interval exercise (HIIE) on ambulatory BP. Twenty-one normotensive men (23.6 ± 3.6 years) completed 2 experimental sessions in a randomized order: (a) control (no exercise) and (b) low-volume HIIE: 10 × 1 minute at 100% of maximal treadmill velocity interspersed with 1 minute of recovery. After each experimental session, an ambulatory BP monitoring was initiated. Paired sample t-test was used to compare BP averages for awake, asleep, and 20-hour periods between the control and the low-volume HIIE sessions. A 2-way repeated measures analysis of variance was used to analyze hourly BP after both experimental sessions. Blood pressure averages during the awake (systolic: 118 ± 6 vs. 122 ± 6 mm Hg; diastolic: 65 ± 7 vs. 67 ± 7 mm Hg) and 20-hour (systolic: 115 ± 7 vs. 118 ± 6 mm Hg; diastolic: 62 ± 7 vs. 64 ± 7 mm Hg) periods were lower after the low-volume HIIE compared with the control (p ≤ 0.05). Systolic and diastolic PEH presented medium (Cohen's d = 0.50-0.67) and small (Cohen's d = 0.29) effect sizes, respectively. Systolic PEH occurred in a greater magnitude during the first 5 hours (3-5 mm Hg). No changes were found in asleep BP (p > 0.05). In conclusion, a single session of low-volume HIIE reduced ambulatory BP in normotensive men. The PEH occurred mainly in systolic BP during the first 5 hours postexercise.

Acute effects of cycling exercise on post-exercise blood pressure in individuals with down syndrome

Purpose. Studies have shown that even a single session of physical exercise lowers blood pressure after its completion. This phenomenon is called post-exercise hypotension (PEH) and has been considered as a non-pharmacological treatment to control blood pressure. However, there are no studies regarding the occurrence of PEH after acute exercise in individuals with Down syndrome (DS). This study aimed to analyse the occurrence of PEH in these subjects and the possible role of exercise intensity. Methods. Ten individuals with DS, of both genders, participated in the study (age, 29 ± 7 years; body mass, 60.7 ± 9 kg; height, 1.48 ± 0.11 m; BMI, 27.6 ± 2.4 kg/m2). The volunteers randomly underwent 2 sessions of exercise on a stationary bike for 20 minutes and 1 control session. Heart rate, systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured after 15 minutes of resting, in the 20

An integrative perspective of the anaerobic threshold

The concept of anaerobic threshold (AT) was introduced during the nineteen sixties. Since then, several methods to identify the anaerobic threshold (AT) have been studied and suggested as novel 'thresholds' based upon the variable used for its detection (i.e. lactate threshold, ventilatory threshold, glucose threshold). These different techniques have brought some confusion about how we should name this parameter, for instance, anaerobic threshold or the physiological measure used (i.e. lactate, ventilation). On the other hand, the modernization of scientific methods and apparatus to detect AT, as well as the body of literature formed in the past decades, could provide a more cohesive understanding over the AT and the multiple physiological systems involved. Thus, the purpose of this review was to provide an integrative perspective of the methods to determine AT.

Extreme Conditioning Program Induced Acute Hypotensive Effects are Independent of the Exercise Session Intensity

The aim of the study was to determine the acute systolic (SBP) and diastolic (DBP) blood pressure, rating of perceived exertion (RPE) and heart rate (HR) responses following two intense training sessions (24 hours apart). Nine male extreme conditioning program (ECP) practitioners with more than 6 months of experience (age 26.7 ± 6.6 years; body mass 78.8 ± 13.2 kg; body fat 13.5 ± 6.2 %) completed two experimental ECP sessions. Cardiovascular variables were measured before, immediately after and every 15 min during a 45 min recovery following each experimental session. Compared with pre-exercise data, our results showed a SBP decrease at 30 min post exercise session 1 (P≤0.05) and at 45 min following exercise session 2. DBP decreased (P≤0.05) at 15 min and 30 min following exercise session 1 and at 30 min after the exercise session 2, respectively. HR remained significantly higher (P≤0.05) 45 min following the first and second exercise session compared with pre-exercise values. Exercise session 1 induced a higher increase in HR (86 ± 11% of HRmax versus 82 ± 12% of HRmax, p = 0.01) and RPE (8.8 ± 1.2 versus 8.0 ± 1.2, p = 0.02) when compared to exercise session 2. In conclusion, post-exercise hypotension occurs following strenuous exercise sessions, regardless of the session design, which may have an important role in the prevention of cardiovascular diseases.

Whole Red Grape Juice Reduces Blood Pressure at Rest and Increases Post-exercise Hypotension

OBJECTIVE

The objective of this study was to evaluate the effect of whole red grape juice (juice) on blood pressure (BP) at rest and on the magnitude of post-exercise hypotension (PEH).

METHODS

This double-blind, randomized controlled study was performed with 26 individuals with hypertension (40 to 59 years old) who were divided into experimental (n = 14) and control (n = 12) groups. Subsequently, the experimental group was subdivided according to the initial BP values. The subjects performed 2 sessions of aerobic exercise on a treadmill (60 minutes, 60%-85% maximum heart rate), separated by a 28-day period of supplementation with a daily dose of juice (150 ml for men and 100 ml for women) or a control drink. BP was measured before, during, and immediately after each exercise session as well as every 10 minutes during the 60-minute post-exercise recovery period.

RESULTS

The BP at rest did not change in the experimental group, but when this group was subdivided by initial BP, the subjects with controlled initial BP (EGCP) achieved a significant reduction (133.3 ± 5.6 to 114.6 ± 12.2 mmHg, p = 0.02); in contrast, the experimental group with borderline hypertensive BP values (EGBP) did not. Intervention with juice did not modify PEH in the experimental group, but when this group was divided as a function of the initial BP, PEH was potentiated at some times in EGCP.

CONCLUSIONS

We conclude that juice promotes a reduction in BP at rest and is also capable of improving PEH in individuals with hypertension, but these effects are dependent on the initial BP values.

Heritability of the affective response to exercise and its correlation to exercise behavior

OBJECTIVES

Individual differences in adolescent exercise behavior are strongly influenced by genetic factors. The affective response to exercise is a potential source of these genetic influences. To test its role in the motivation to exercise, we estimated the heritability of the affective responses during and after exercise and the overlap with the genetic factors influencing regular voluntary exercise behavior.

DESIGN

226 twin pairs and 38 siblings completed two submaximal exercise tests on a cycle ergometer and a treadmill and a maximal exercise test on a cycle ergometer. Affective responses were assessed by the Feeling Scale (FS), Borg's Rating of Perceived Exertion (RPE) and the Activation-Deactivation Adjective Checklist (AD ACL).

METHODS

Multivariate structural equation modeling was used to estimate heritability of the affective responses during and after submaximal and maximal exercise and the (genetic) correlation with self-reported regular voluntary exercise behavior over the past year.

RESULTS

Genetic factors explained 15% of the individual differences in FS responses during the cycle ergometer test, as well as 29% and 35% of the individual differences in RPE during the cycle ergometer and treadmill tests, respectively. For the AD ACL scales, heritability estimates ranged from 17% to 37% after submaximal exercise and from 12% to 37% after maximal exercise. Without exception, more positive affective responses were associated with higher amounts of regular exercise activity (.15 < r < .21) and this association was accounted for by an overlap in genetic factors influencing affective responding and exercise behavior.

CONCLUSIONS

We demonstrate low to moderate heritability estimates for the affective response during and after exercise and significant (genetic) associations with regular voluntary exercise behavior. These innate individual differences in the affective responses to exercise should be taken into account in interventions aiming to motivate adolescents to adopt and maintain regular exercise.

Significant role of the cardiopostural interaction in blood pressure regulation during standing

Cardiovascular and postural control systems have been studied independently despite the increasing evidence showing the importance of cardiopostural interaction in blood pressure regulation. In this study, we aimed to assess the role of the cardiopostural interaction in relation to cardiac baroreflex in blood pressure regulation under orthostatic stress before and after mild exercise. Physiological variables representing cardiovascular control (heart rate and systolic blood pressure), lower limb muscle activation (electromyography), and postural sway (center of pressure derived from force and moment data during sway) were measured from 17 healthy participants (25 ± 2 yr, 9 men and 8 women) during a sit-to-stand test before and after submaximal exercise. The cardiopostural control (characterized by baroreflex-mediated muscle-pump effect in response to blood pressure changes, i.e., muscle-pump baroreflex) was assessed using wavelet transform coherence and causality analyses in relation to the baroreflex control of heart rate. Significant cardiopostural blood pressure control was evident counting for almost half of the interaction time with blood pressure changes that observed in the cardiac baroreflex (36.6-72.5% preexercise and 34.7-53.9% postexercise). Thus, cardiopostural input to blood pressure regulation should be considered when investigating orthostatic intolerance. A reduction of both cardiac and muscle-pump baroreflexes in blood pressure regulation was observed postexercise and was likely due to the absence of excessive venous pooling and a less stressed system after mild exercise. With further studies using more effective protocols evoking venous pooling and muscle-pump activity, the cardiopostural interaction could improve our understanding of the autonomic control system and ultimately lead to a more accurate diagnosis of cardiopostural dysfunctions.NEW & NOTEWORTHY We examined the interaction between cardiovascular and postural control systems during standing before and after mild exercise. Significant cardiopostural input to blood pressure regulation was shown, suggesting the importance of cardiopostural integration when investigating orthostatic hypotension. In addition, we observed a reduction of baroreflex-mediated blood pressure regulation after exercise.

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.

Acute blood pressure response in hypertensive elderly women immediately after water aerobics exercise: A crossover study

Water aerobics exercise is widely recommended for elderly people. However, little is known about the acute effects on hemodynamic variables. Thus, we assessed the effects of a water aerobic session on blood pressure in hypertensive elderly women. Fifty hypertensive elderly women aged 67.8 ± 4.1 years, 1.5 ± 0.6 m high and BMI 28.6 ± 3.9 kg/m², participated in a crossover clinical trial. The experiment consisted of a 45-minute water aerobics session (70%-75% HRmax adjusted for the aquatic environment) (ES) and a control session (no exercise for 45 minutes) (CS). Heart rate was monitored using a heart rate monitor and systolic blood pressure (SBP) and diastolic (DBP) measurements were taken using a semi-automatic monitor before and immediately after the sessions, and at 10, 20 and 30 minutes thereafter. It was using a generalized estimating equation (GEE) with Bonferroni's post-hoc test (p < 0.05). At the end of the experimental session, ES showed a rise in SBP of 17.4 mmHg (14.3%, p < 0.001) and DBP of 5.4 mmHg (7.8%, p < 0.001) compared to CS. At 10 minutes after exercise, BP declined in ES by a greater magnitude than in CS (SBP 7.5 mmHg, 6.2%, p = 0.005 and DBP 3.8 mmHg, 5.5%, p = 0.013). At 20 minutes after exercise and thereafter, SBP and DBP were similar in both ES and CS. In conclusion, BP returned to control levels within 10-20 minutes remaining unchanged until 30 minutes after exercise, and post-exercise hypotension was not observed. Besides, BP changed after exercise was a safe rise of small magnitude for hypertensive people.

GABA-producing Bifidobacterium dentium modulates visceral sensitivity in the intestine

BACKGROUND

Recurrent abdominal pain is a common and costly health-care problem attributed, in part, to visceral hypersensitivity. Increasing evidence suggests that gut bacteria contribute to abdominal pain perception by modulating the microbiome-gut-brain axis. However, specific microbial signals remain poorly defined. γ-aminobutyric acid (GABA) is a principal inhibitory neurotransmitter and a key regulator of abdominal and central pain perception from peripheral afferent neurons. Although gut bacteria are reported to produce GABA, it is not known whether the microbial-derived neurotransmitter modulates abdominal pain.

METHODS

To investigate the potential analgesic effects of microbial GABA, we performed daily oral administration of a specific Bifidobacterium strain (B. dentiumATCC 27678) in a rat fecal retention model of visceral hypersensitivity, and subsequently evaluated pain responses.

KEY RESULTS

We demonstrate that commensal Bifidobacterium dentium produces GABA via enzymatic decarboxylation of glutamate by GadB. Daily oral administration of this specific Bifidobacterium (but not a gadB deficient) strain modulated sensory neuron activity in a rat fecal retention model of visceral hypersensitivity.

CONCLUSIONS & INFERENCES

The functional significance of microbial-derived GABA was demonstrated by gadB-dependent desensitization of colonic afferents in a murine model of visceral hypersensitivity. Visceral pain modulation represents another potential health benefit attributed to bifidobacteria and other GABA-producing species of the intestinal microbiome. Targeting GABAergic signals along this microbiome-gut-brain axis represents a new approach for the treatment of abdominal pain.

Blood pressure and autonomic responses following isolated and combined aerobic and resistance exercise in hypertensive older women

PURPOSE

This study aimed to compare blood pressure (BP) after isolated and combined sessions of aerobic and resistance exercises in hypertensive older women. Heart rate (HR) and heart rate variability (HRV) were included as additional variables.

METHODS

Twenty-one older women (63±1.9 years; 69.9±2.7 kg; 158.8±2.1 cm) with controlled hypertension (resting BP = 132.2 ± 3.1/74.1 ± 4.0 mmHg) performed four random sessions on different days: 1) aerobic exercise (AE: treadmill walking/running; 40 min; 50-60% HR_reserve); 2) resistance exercise (RE: 8 exercises; 3 sets; 15 reps; 40% 1RM)); 3) aerobic exercise followed by resistance exercise (A+R); 4); control (CON). BP, HR and HRV were measured at rest and during 180 min after the sessions.

RESULTS

The AE and A+R sessions demonstrated significant decreases in SBP and DBP (30, 60, 120, and 180 min; P < 0.05) and increases in HR (30 and 60 min; P < 0.05) compared to the CON. The RE session demonstrated significant reductions compared to the CON only for DBP (120 and 180 min; P < 0.05). No significant differences were observed in HRV between resting and all sessions.

CONCLUSION

All sessions that involved aerobic exercise (AE and A+R) caused postexercise hypotension in comparison to the CON, with no differences in HRV.

Contact Karate Promotes Post-Exercise Hypotension in Young Adult Males

Background

Worldwide, systemic arterial hypertension is a leading cause of death and non-communicable cardiovascular disease. A major factor contributing to this disease is a sedentary lifestyle. However, physical exercise, such as martial arts, may be an option for blood pressure (BP) control. The magnitude of post-exercise hypotension is associated with a prolonged decrease in BP in normotensive and hypertensive individuals.

Objectives

The present study aimed to verify the effects of a Contact Karate (CK) session on BP responses during a post-exercise recovery period in young adults.

Patients and Methods

Thirty-two male CK athletes volunteered (28.2 ± 6.7 years; 77.0 ± 5.7 kg; and 176.0 ± 4.7 cm) and underwent one CK session (50 minutes) and a control session in which no exercise was performed and the individuals remain seated during the whole time. BP was measured during rest (before sessions), as well as on the 15th, 30th, 45th, and 60th minutes of the post-exercise recovery.

Results

The systolic (SBP), diastolic (DBP), and mean arterial pressure (MAP) were significantly lower at the post-exercise period compared to pre-exercise rest (P < 0.05), with the largest reductions being observed at the 60th minutes of recovery [SBP (rest: 125.9 ± 4.7 vs. 60th minutes of recovery: 111.7 ± 5.4 mmHg); DBP (rest: 78.8 ± .7 vs. 60th minutes of recovery: 69.8 ± 2.7 mmHg)] and at the same periods of post-exercise recovery of the control session.

Conclusions

A single CK session can promote a decrease in BP for at least 60 minutes after performing this type of exercise in young adults.

Exercise prevents development of autonomic dysregulation and hyperalgesia in a mouse model of chronic muscle pain

Chronic musculoskeletal pain (CMP) conditions, like fibromyalgia, are associated with widespread pain and alterations in autonomic functions. Regular physical activity prevents the development of CMP and can reduce autonomic dysfunction. We tested if there were alterations in autonomic function of sedentary mice with CMP, and whether exercise reduced the autonomic dysfunction and pain induced by CMP. Chronic musculoskeletal pain was induced by 2 intramuscular injections of pH 5.0 in combination with a single fatiguing exercise task. A running wheel was placed into cages so that the mouse had free access to it for either 5 days or 8 weeks (exercise groups) and these animals were compared to sedentary mice without running wheels. Autonomic function and nociceptive withdrawal thresholds of the paw and muscle were assessed before and after induction of CMP in exercised and sedentary mice. In sedentary mice, we show decreased baroreflex sensitivity, increased blood pressure variability, decreased heart rate variability, and decreased withdrawal thresholds of the paw and muscle 24 hours after induction of CMP. There were no sex differences after induction of the CMP in any outcome measure. We further show that both 5 days and 8 weeks of physical activity prevent the development of autonomic dysfunction and decreases in withdrawal threshold induced by CMP. Thus, this study uniquely shows the development of autonomic dysfunction in animals with chronic muscle hyperalgesia, which can be prevented with as little as 5 days of physical activity, and suggest that physical activity may prevent the development of pain and autonomic dysfunction in people with CMP.

The blood pressure-lowering effect of a single bout of resistance exercise: A systematic review and meta-analysis of randomised controlled trials

BACKGROUND

Current exercise guidelines recommend aerobic types of exercises on most days of the week, supplemented with dynamic resistance exercise twice weekly. Whereas the blood pressure (BP)-lowering effects of a single session of aerobic exercise have been well studied, less is known about the hypotensive effect of a single bout of resistance exercise.

OBJECTIVES

To evaluate the transient effect of resistance exercise on BP by means of meta-analytic techniques.

METHODS

A systematic electronic search in Medline, Scientific Electronic Library Online (SciELO), Latin American and Caribbean Health Sciences Literature (LILACS), Elton B Stephens Company (EBSCO), EMBASE and SPORTDiscus was completed in March 2015 identifying randomised controlled trials investigating the effect of a single bout of resistance exercise on resting or ambulatory BP in healthy adults. A subsequent meta-analysis was performed.

RESULTS

The meta-analysis involved 30 studies, 81 interventions and 646 participants (normotensive (n = 505) or hypertensive (n = 141)). A single bout of resistance exercise elicited small-to-moderate reductions in office systolic BP at 60 minutes postexercise [-3.3 (-4.0 to -2.6)/-2.7 (-3.2 to -2.1) mmHg (CI 95%)], 90 minutes postexercise [-5.3 (-8.5 to -2.1)/-4.7 (-6.9 to -2.4) mmHg (CI 95%)] and in 24-hour ambulatory BP [-1.7 (-2.8 to -0.67)/-1.2 (-2.4 to -0.022) mmHg (CI 95%)] compared to a control session. The reduction in office BP was more pronounced in hypertensive compared to normotensive individuals (p < 0.01), when using larger muscle groups (p < 0.05) and when participants were recovering in the supine position (p < 0.01).

CONCLUSION

A single bout of resistance exercise can have a BP-lowering effect that last for up to 24 hours. Supine recovery and the use of larger muscle groups resulted in greater BP reductions after resistance exercise.

Low-Volume Intense Exercise Elicits Post-exercise Hypotension and Subsequent Hypervolemia, Irrespective of Which Limbs Are Exercised

Introduction: Exercise reduces arterial and central venous blood pressures during recovery, which contributes to its valuable anti-hypertensive effects and to facilitating hypervolemia. Repeated sprint exercise potently improves metabolic function, but its cardiovascular effects (esp. hematological) are less well-characterized, as are effects of exercising upper versus lower limbs. The purposes of this study were to identify the acute (<24 h) profiles of arterial blood pressure and blood volume for (i) sprint intervals versus endurance exercise, and (ii) sprint intervals using arms versus legs.

Methods: Twelve untrained males completed three cycling exercise trials; 50-min endurance (legs), and 5^*30-s intervals using legs or arms, in randomized and counterbalanced sequence, at a standardized time of day with at least 8 days between trials. Arterial pressure, hemoglobin concentration and hematocrit were measured before, during and across 22 h after exercise, the first 3 h of which were seated rest.

Results: The post-exercise hypotensive response was larger after leg intervals than endurance (AUC: 7540 ± 3853 vs. 3897 ± 2757 mm Hg·min, p = 0.049, 95% CI: 20 to 6764), whereas exercising different limbs elicited similar hypotension (arms: 6420 ± 3947 mm Hg·min, p = 0.48, CI: −1261 to 3896). In contrast, arterial pressure at 22 h was reduced after endurance but not after leg intervals (−8 ± 8 vs. 0 ± 7 mm Hg, p = 0.04, CI: 7 ± 7) or reliably after arm intervals (−4 ± 8 mm Hg, p = 0.18 vs. leg intervals). Regardless, plasma volume expansion at 22 h was similar between leg intervals and endurance (both +5 ± 5%; CI: −5 to 5%) and between leg and arm intervals (arms: +5 ± 7%, CI: −8 to 5%).

Conclusions: These results emphasize the relative importance of central and/or systemic factors in post-exercise hypotension, and indicate that markedly diverse exercise profiles can induce substantive hypotension and subsequent hypervolemia. At least for endurance exercise, this hypervolemia may not depend on the volume of post-exercise hypotension. Finally, endurance exercise led to reduced blood pressure the following day, but sprint interval exercise did not.

Combined effects of aerobic exercise and l-arginine ingestion on blood pressure in normotensive postmenopausal women: A crossover study

After menopause the incidence of cardiovascular diseases increases in women. A decrease in nitric oxide (NO) bioavailability has been pointed out to play a major role in this phenomenon. Since it is believed that l-arginine administration could improve NO bioavailability, the aim of this study was to examine the effects of acute l-arginine administration associated with aerobic exercise on blood pressure (BP), redox state and inflammatory biomarkers in normotensive postmenopausal women (NPW). Sixteen volunteers (57±6yr) were subjected to four experimental sessions (crossover design): arginine+exercise (A-E); arginine (ARG); exercise+placebo (EXE); control (CON). Each session was initiated with either 9g of l-arginine ingestion (ARG or A-E days), placebo (EXE day), or nothing (CON day). The participants performed 30min of aerobic exercise (A-E and EXE days) or sitting rest (CON and ARG days). Blood samples were collected before each session and 45min after the intervention. Office BP and ambulatory blood pressure monitoring (ABPM) were evaluated. NO/cGMP pathway, redox state and inflammatory biomarkers were measured. Systolic BP decreased during the 24-hour in A-E and EXE sessions. However, diastolic BP reduced only in A-E session. No changes were found in the biomarkers concentrations. In conclusion, the association was effective in lowering diastolic BP in NPW. Additionally, physical exercise alone promoted a long lasting effect on systolic BP measured by ABPM in this population, although this beneficial effect was not associated with changes in the cardio-inflammatory biomarkers. Possibly, other factors such as neural influences could be mediating this effect.

Long-term moderate exercise accelerates the recovery of stress-evoked cardiovascular responses

Psychological stress is an important global health problem. It is well documented that stress increases the incidences of various cardiovascular disorders. Regular exercise is known to reduce resting blood pressure (BP) and heart rate (HR). This study was designed to clarify the effects of long-term exercise on stress-evoked cardiovascular responses and to emphasize post-stress recovery effects. Male Wistar rats underwent 8 weeks of moderate treadmill training, with cardiovascular responses, autonomic nervous system activities and local Fos reactivity changes in the cardiovascular regulation center were monitored before, during and after immobilization stress. A spectral analysis of cardiovascular parameters was used to examine autonomic nervous activities. We found that long-term exercise (i) lowered resting BP, HR and sympathetic activity, but increased resting parasympathetic activity and baroreflex sensitivity (BRS); (ii) accelerated post-stress recovery of stress-evoked cardiovascular and sympathetic responses along with increased BRS and (iii) accelerated post-stress recovery of stress-evoked neuron activations in the paraventricular nucleus, but delayed it in the nucleus of the tractus solitarius. We conclude that, in rats, long-term exercise accelerated recovery of stress-evoked cardiovascular responses differentially altering hypothalamic and medullar neuron activities.

Similar hypotensive effects of combined aerobic and resistance exercise with 1 set versus 3 sets in women with metabolic syndrome

The aim of the present study was to compare the response of systolic blood pressure (SBP), mean blood pressure (MBP) and diastolic blood pressure (DBP) following combined training with 1 set or with 3 sets of resistance exercise (RE). Sixteen women with metabolic syndrome (MetS) were randomly assigned to perform two combined exercise protocols and a control session (CON): 1-set, 30 min of aerobic exercise (AE) at 65-70% of reserve heart rate and 1 set of 8-12 repetitions at 80% of 10-RM in six resistance exercises; 3-sets, same protocol but with 3 sets; and CON, 30 min of seated rest. The SBP, MBP and DBP were measured before and every 15 min during 90 min following the experimental sessions. The SBP displayed a decrease (P ≤ 0.05) during the 90 min following the RE session with 1-set and 3-set, while MBP was decreased (P ≤ 0.05) up to 75 min after 1-set and up to 30 min after the 3-set exercise session compared with pre-intervention values. There was a decrease in DBP only for the greatest individual decrease following 1-set (-6.1 mmHg) and 3-set (-4.9 mmHg) combined exercise sessions, without differences between them. The rate-pressure product and heart rate remained significantly higher (P ≤ 0.05) 75 min and 90 min after the combined exercise session with 1- and 3-sets compared with the CON, respectively. In conclusion, a low-volume RE combined with AE resulted in similar decrease of SBP when compared with RE with 3-sets in women with MetS, which could be beneficial in situations of limited time.

Postexercise hypotension after maximal short-term incremental exercise depends on exercise modality

This study investigated postexercise hypotension (PEH) after maximal cardiopulmonary exercise testing (CPET) performed using different exercise modalities. Twenty healthy men (aged 23 ± 3 years) performed 3 maximal CPETs (cycling, walking, and running), separated by 72 h in a randomized, counter-balanced order. Systolic (SBP) and diastolic blood pressure (DBP), heart rate, cardiac output, systemic vascular resistance (SVR), autonomic function (spontaneous baroreflex sensitivity (BRS) and heart rate variability (HRV)), and energy expenditure (EE) were assessed during a 60-min nonexercise control session and for 60 min immediately after each CPET. Total exercise volume (EE during CPET plus 60 min recovery) was significantly higher in running versus cycling and walking CPETs (P ≤ 0.001). Compared with control, only SBP after running CPET was significantly reduced (Δ = −6 ± 8 mm Hg; P < 0.001). Heart rate and cardiac output were significantly increased (P < 0.001) and SVR significantly decreased (P < 0.001) postexercise. BRS and HRV decreased after all CPETs (P < 0.001), whereas sympatho-vagal balance (low- and high-frequency (LF:HF) ratio) increased significantly after all exercise conditions, especially after running CPET (P < 0.001). Changes in SVR, BRS, sympathetic activity (low-frequency component of HRV), and LF:HF ratio were negatively correlated to variations in SBP (range −0.69 to −0.91; P < 0.001) and DBP (range −0.58 to −0.93; P ≤ 0.002). These findings suggest that exercise mode or the total exercise volume are major determinants of PEH magnitude in healthy men. Because of the running CPET, the PEH was primarily related to a decrease in SVR and to an increase in sympatho-vagal balance, which might be a reflex response to peripheral vasodilatation after exercise.

Hemodynamic responses during and after multiple sets of stretching exercises performed with and without the Valsalva maneuver

OBJECTIVE

This study investigated the acute hemodynamic responses to multiple sets of passive stretching exercises performed with and without the Valsalva maneuver.

METHODS

Fifteen healthy men aged 21 to 29 years with poor flexibility performed stretching protocols comprising 10 sets of maximal passive unilateral hip flexion, sustained for 30 seconds with equal intervals between sets. Protocols without and with the Valsalva maneuver were applied in a random counterbalanced order, separated by 48-hour intervals. Hemodynamic responses were measured by photoplethysmography pre-exercise, during the stretching sets, and post-exercise.

RESULTS

The effects of stretching sets on systolic and diastolic blood pressure were cumulative until the fourth set in protocols performed with and without the Valsalva maneuver. The heart rate and rate pressure product increased in both protocols, but no additive effect was observed due to the number of sets. Hemodynamic responses were always higher when stretching was performed with the Valsalva maneuver, causing an additional elevation in the rate pressure product.

CONCLUSIONS

Multiple sets of unilateral hip flexion stretching significantly increased blood pressure, heart rate, and rate pressure product values. A cumulative effect of the number of sets occurred only for systolic and diastolic blood pressure, at least in the initial sets of the stretching protocols. The performance of the Valsalva maneuver intensified all hemodynamic responses, which resulted in significant increases in cardiac work during stretching exercises.

Hypotensive response magnitude and duration in hypertensives: continuous and interval exercise

BACKGROUND

Although exercise training is known to promote post-exercise hypotension, there is currently no consistent argument about the effects of manipulating its various components (intensity, duration, rest periods, types of exercise, training methods) on the magnitude and duration of hypotensive response.

OBJECTIVE

To compare the effect of continuous and interval exercises on hypotensive response magnitude and duration in hypertensive patients by using ambulatory blood pressure monitoring (ABPM).

METHODS

The sample consisted of 20 elderly hypertensives. Each participant underwent three ABPM sessions: one control ABPM, without exercise; one ABPM after continuous exercise; and one ABPM after interval exercise. Systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR) and double product (DP) were monitored to check post-exercise hypotension and for comparison between each ABPM.

RESULTS

ABPM after continuous exercise and after interval exercise showed post-exercise hypotension and a significant reduction (p < 0.05) in SBP, DBP, MAP and DP for 20 hours as compared with control ABPM. Comparing ABPM after continuous and ABPM after interval exercise, a significant reduction (p < 0.05) in SBP, DBP, MAP and DP was observed in the latter.

CONCLUSION

Continuous and interval exercise trainings promote post-exercise hypotension with reduction in SBP, DBP, MAP and DP in the 20 hours following exercise. Interval exercise training causes greater post-exercise hypotension and lower cardiovascular overload as compared with continuous exercise.

Neurovascular control following small muscle-mass exercise in humans

Sustained postexercise vasodilation, which may be mediated at both a neural and vascular level, is seen in previously active skeletal muscle vascular beds following both large and small muscle-mass exercise. Blunted sympathetic vascular transduction and a downward resetting of the arterial baroreflex contribute to this vasodilation after cycling (large muscle-mass exercise), but it is unknown if these responses also contribute to sustained vasodilation following small muscle-mass exercise. This study aimed to determine if baroreflex sensitivity is altered, the baroreflex is reset, or if sympathetic vascular transduction is blunted following small muscle-mass exercise. Eleven healthy, college-aged subjects (five males, six females) completed one-leg dynamic knee-extension exercise for 1 h at 60% of peak power output. While cardiovagal baroreflex sensitivity was increased ∼23% postexercise relative to preexercise (P < 0.05), vascular and integrated baroreflex sensitivity were not altered following exercise (P = 0.31 and P = 0.48). The baroreflex did not exhibit resetting (P > 0.69), and there was no evidence of changes in vascular transduction following exercise (P = 0.73). In conclusion, and in contrast to large muscle-mass exercise, it appears that small muscle-mass exercise produces a sustained postexercise vasodilation that is largely independent of central changes in the baroreflex.

Effects of aerobic exercise intensity on 24-h ambulatory blood pressure in individuals with type 2 diabetes and prehypertension

[Purpose] To verify the effects of different intensities of aerobic exercise on 24-hour ambulatory blood pressure (BP) responses in individuals with type 2 diabetes mellitus (T2D) and prehypertension. [Subjects and Methods] Ten individuals with T2D and prehypertension (55.8 ± 7.7 years old; blood glucose 133.0 ± 36.7 mg·dL⁻¹ and awake BP 130.6 ± 1.6/ 80.5 ± 1.8 mmHg) completed three randomly assigned experiments: non-exercise control (CON) and exercise at moderate (MOD) and maximal (MAX) intensities. Heart rate (HR), BP, blood lactate concentrations ([Lac]), oxygen uptake (VO₂), and rate of perceived exertion (RPE) were measured at rest, during the experimental sessions, and during the 60 min recovery period. After this period, ambulatory blood pressure was monitored for 24 h. [Results] The results indicate that [Lac] (MAX: 6.7±2.0 vs. MOD: 3.8±1.2 mM), RPE (MAX: 19±1.3 vs. MOD: 11±2.3) and VO₂peak (MAX: 20.2±4.1 vs. MOD: 14.0±3.0 mL·kg⁻¹·min⁻¹) were highest following the MAX session. Compared with CON, only MAX elicited post-exercise BP reduction that lasted for 8 h after exercise and during sleep. [Conclusion] A single session of aerobic exercise resulted in 24 h BP reductions in individuals with T2D, especially while sleeping, and this reduction seems to be dependent on the intensity of the exercise performed.

Resistance exercise with different volumes: blood pressure response and forearm blood flow in the hypertensive elderly

Background

The purpose of this study was to evaluate the effect of two sessions of resistance exercise with different volumes on post-exercise hypotension, forearm blood flow, and forearm vascular resistance in hypertensive elderly subjects.

Methods

The study was conducted with ten hypertensive elderly (65±3 years, 28.7±3 kg/m²) subjected to three experimental sessions, ie, a control session, exercise with a set (S1), and exercise with three sets (S3). For each session, the subjects were evaluated before and after intervention. In the pre-intervention period, blood pressure, forearm blood flow, and forearm vascular resistance were measured after 10 minutes of rest in the supine position. Thereafter, the subjects were taken to the gym to perform their exercise sessions or remained at rest during the same time period. Both S1 and S3 comprised a set of ten repetitions of ten exercises, with an interval of 90 seconds between exercises. Subsequently, the measurements were again performed at 10, 30, 50, 70, and 90 minutes of recovery (post-intervention) in the supine position.

Results

Post-exercise hypotension was greater in S3 than in S1 (systolic blood pressure, −26.5±4.2 mmHg versus −17.9±4.7 mmHg; diastolic blood pressure, −13.8±4.9 mmHg versus −7.7±5 mmHg, P<0.05). Similarly, forearm blood flow and forearm vascular resistance changed significantly in both sessions with an increase and decrease, respectively, that was more evident in S3 than in S1 (P<0.05).

Conclusion

Resistance exercises with higher volume were more effective in causing post-exercise hypotension, being accompanied by an increase in forearm blood flow and a reduction of forearm vascular resistance.

Acute effects of physical exercise in type 2 diabetes: A review

The literature has shown the efficiency of exercise in the control of type 2 diabetes (T2D), being suggested as one of the best kinds of non-pharmacological treatments for its population. Thus, the scientific production related to this phenomenon has growing exponentially. However, despite its advances, still there is a lack of studies that have carried out a review on the acute effects of physical exercise on metabolic and hemodynamic markers and possible control mechanisms of these indicators in individuals with T2D, not to mention that in a related way, these themes have been very little studied today. Therefore, the aim of this study was to organize and analyze the current scientific production about the acute effects of physical exercise on metabolic and hemodynamic markers and possible control mechanisms of these indicators in T2D individuals. For such, a research with the following keywords was performed: -exercise; diabetes and post-exercise hypotension; diabetes and excess post-exercise oxygen consumption; diabetes and acute effects in PUBMED, SCIELO and HIGHWIRE databases. From the analyzed studies, it is possible to conclude that, a single exercise session can promote an increase in the bioavailability of nitric oxide and elicit decreases in postexercise blood pressure. Furthermore, the metabolic stress from physical exercise can increase the oxidation of carbohydrate during the exercise and keep it, in high levels, the post exercise consumption of O_², this phenomenon increases the rate of fat oxidation during recovery periods after exercise, improves glucose tolerance and insulin sensitivity and reduces glycemia between 2-72 h, which seems to be dependent on the exercise intensity and duration of the effort.

Greater autonomic modulation during post-exercise hypotension following high-intensity interval exercise in endurance-trained men and women

PURPOSE

An acute reduction in blood pressure observed after a single bout of exercise is termed post-exercise hypotension (PEH). In contrast to moderate intensity aerobic exercise, little is known about the PEH response following high-intensity interval exercise. The present purpose is to assess how sex and training status impact PEH following high-intensity interval exercise.

METHODS

Cardiac volumes and function via echocardiography were measured in 40 normotensive, endurance-trained (ET) and normally active (NA) men and women (Age ± SD = 30.5 ± 5.7) following high-intensity interval cycle exercise. Continuous measurements of ECG and beat-by-beat blood pressure were collected before and 30 min post-exercise for determination of cardiovagal baroreflex function (BRS and αLF), spectral analysis of heart rate and systolic blood pressure (SBP LF).

RESULTS

Post-exercise systolic BP was significantly reduced from baseline, occurring to a greater degree in ET compared with NA (-12.9 vs. -5.3 mmHg, P = 0.008), while mean arterial pressure was similarly reduced in all groups (-4.6 mmHg, P = 0.003). Despite reduced SVI and TPRI, CI was increased post-exercise (P < 0.01). ET experienced a greater decrease in αLF (P = 0.037) and increase in SBP LF (P = 0.017) than NA. Lean body mass was a significant predictor of change in SBP LF (Std. β = 0.735, P = 0.008).

CONCLUSIONS

These results characterize greater depressions in cardiovagal baroreflex function, and increased sympathetic activity, following vigorous exercise in endurance-trained individuals compared with normally active participants. This heightened sympathovagal balance after high-intensity exercise may be a compensatory mechanism in response to greater peripheral blood flow demands following vigorous exercise.