Sympathoadrenergic mechanisms in reduced hemodynamic stress responses after exercise

The effects of acute exercise on stress reactivity assessed via a multidimensional approach: a systematic review

Psychological stress is associated with numerous deleterious health effects. Accumulating evidence suggests acute exercise reduces stress reactivity. As stressors activate a wide array of psychological and physiological systems it is imperative stress responses are examined through a multidimensional lens. Moreover, it seems prudent to consider whether stress responses are influenced by exercise intervention characteristics such as modality, duration, intensity, timing, as well as participant fitness/physical activity levels. The current review therefore examined the role of acute exercise on stress reactivity through a multidimensional approach, as well as whether exercise intervention characteristics and participant fitness/physical activity levels may moderate these effects. Stress reactivity was assessed via heart rate, blood pressure, cortisol, catecholamines, and self-report. A systematic search following PRISMA guidelines of five databases was updated in November 2022. Reviewed studies met the following criteria: English language, participants aged ≥ 18, use of acute exercise, use of a validated stress-inducing task, and assessment(s) of stress reactivity. Thirty-one studies (1386 participants) were included. Acute exercise resulted in reliable reductions to blood pressure and cortisol. Acute exercise yielded mostly negligible effects on heart rate reactivity and negligible effects on self-report measures. As for exercise intervention characteristics, intensity-dependent effects were present, such that higher intensities yielded larger reductions to reactivity measures, while limited evidence was present for duration, modality, and timing-dependent effects. Regarding participant fitness/physical activity levels, the effects on stress reactivity were mixed. Future work should standardize the definitions and assessment time points of stress reactivity, as well as investigate the interaction between physiological and psychological stress responses in real-world contexts.

Lifestyle Factors and Cancer: A Narrative Review

Lifestyle factors and their impact on cancer prevention, prognosis, and survivorship are increasingly recognized in the medical literature. Lifestyle factors are primarily defined here as diet and physical activity. We conducted a narrative review of the primary published data, including randomized controlled trials and prospective studies, on the impact of primary lifestyle factors on oncogenesis and clinical outcomes in the preventative and survivorship setting. First, we discuss the oncogenic mechanisms behind primary lifestyle factors (diet, physical activity and, within these 2, obesity). Then, we discuss the impact of adherence to lifestyle guidelines and dietary patterns on cancer incidence based on primary data. Owing to the plethora of published literature, to summarize the data in a more efficient manner, we describe the role of physical activity on cancer incidence using summative systematic reviews. We end by synthesizing the primary data on lifestyle factors in the survivorship setting and conclude with potential future directions. In brief, the various large-scale studies investigating the role diet and physical activity have reported a beneficial effect on cancer prevention and survivorship. Although the impact of single lifestyle factors on cancer incidence risk reduction is generally supported, holistic approaches to address the potential synergistic impact of multiple lifestyle factors together in concert is limited. Future research to identify the potentially synergistic effects of lifestyle modifications on oncogenesis and clinical outcomes is needed, particularly in cancer subtypes beyond colorectal and breast cancers.

Acute stress imparts a transient benefit to task-switching that is not modulated following a single bout of exercise

Introduction

Cognitive flexibility represents a core component of executive function that promotes the ability to efficiently alternate-or "switch"-between different tasks. Literature suggests that acute stress negatively impacts cognitive flexibility, whereas a single bout of aerobic exercise supports a postexercise improvement in cognitive flexibility. Here, we examined whether a single bout of aerobic exercise attenuates a stress-induced decrement in task-switching.

Materials and Methods

Forty participants (age range = 19-30) completed the Trier Social Stress Test (TSST) and were randomized into separate Exercise or Rest groups entailing 20-min sessions of heavy intensity exercise (80% of heart rate maximum via cycle ergometer) or rest, respectively. Stress induction was confirmed via state anxiety and heart rate. Task-switching was assessed prior to the TSST (i.e., pre-TSST), following the TSST (i.e., post-TSST), and following Exercise and Rest interventions (i.e., post-intervention) via pro- (i.e., saccade to veridical target location) and antisaccades (i.e., saccade mirror-symmetrical to target location) arranged in an AABB task-switching paradigm. The underlying principle of the AABB paradigm suggests that when prosaccades are preceded by antisaccades (i.e., task-switch trials), the reaction times are longer compared to their task-repeat counterparts (i.e., unidirectional prosaccade switch-cost).

Results

As expected, the pre-TSST assessment yielded a prosaccade switch cost. Notably, post-TSST physiological measures indicated a reliable stress response and at this assessment a null prosaccade switch-cost was observed. In turn, post-intervention assessments revealed a switch-cost independent of Exercise and Rest groups.

Conclusion

Accordingly, the immediate effects of acute stress supported improved task-switching in young adults; however, these benefits were not modulated by a single bout of aerobic exercise.

A single session of exercise reduces blood pressure reactivity to stress: a systematic review and meta-analysis

Stressful situations are common in everyday life and disturb homeostasis. So, an exercise session is a strategy to mitigate blood pressure (BP) peaks in response to stress (i.e., BP reactivity), decreasing the cardiovascular risk. This is a systematic review and meta-analysis that aims to verify the effects of a single session of physical exercises on BP reactivity to stress in adults. The searches were performed in digital databases (MEDLINE, LILACS, EMBASE, SPORTDiscus, and PsycInfo) and 29 studies were included, totaling 795 individuals (quantitative analysis: k = 25, n = 659). As for exercise characteristics, 21 of the 29 studies focused on aerobic exercises, and 23 studies focused on low to moderate intensities. As for the stress tests, we have them in the following order from the most to the least frequent: stroop color and word test, cold pressor test, arithmetic test, public speaking, handgrip, trier social stress test, and study task. Favorable metanalytic results (standardized mean differences through random-effects approach) for the exercises were found, with attenuated reactivity in systolic BP (pooled effect size = - 0.38 [- 0.49; - 0.27], representing average reductions of 3.7 ± 3.8 mmHg), diastolic BP (pooled effect size = - 0.51 [- 0.70; - 0.33], representing average reductions of 2.9 ± 3.7 mmHg), and mean BP (pooled effect size = - 0.51 [- 0.72; - 0.31], representing average reductions of 4.1 ± 3.3 mmHg). So, acute physical exercise lowers systolic, diastolic, and mean blood pressure reactivity in response to stressor tasks. However, given the small magnitude of effects, the clinical relevance of this result must be interpreted with caution and be better explored.

Mat Pilates training and blood pressure reactivity responses to psychological stress: comparison between normotensive and hypertensive postmenopausal women

OBJECTIVES

The aim of this study is to compare resting blood pressure and blood pressure reactivity responses to psychological stress in normotensive and hypertensive postmenopausal women after 12 weeks of Mat Pilates training.

METHODS

Twenty-three hypertensive and 24 normotensive postmenopausal women, performed Mat Pilates training 3× a week for 12 weeks. Before and after the intervention, resting blood pressure, heart rate, and blood pressure reactivity to psychological stress through the electronic version of Stroop test protocol (3 minutes) were measured. We calculated the variation (Δ) of blood pressure (peak of blood pressure during the Stroop stress test minus resting blood pressure before test).

RESULTS

The two-way ANOVA showed that the Δ of systolic blood pressure, diastolic blood pressure, and the mean blood pressure was reduced (P < 0.05) after training only in the hypertensive. The resting systolic, diastolic, and mean blood pressures decreased by (P < 0.05) over time in both groups with no interaction or difference.

CONCLUSION

Mat Pilates was able to reduce resting blood pressure in both hypertensive and normotensive, and blood pressure reactivity after psychological stress in hypertensive but not in normotensive postmenopausal women.

Can Acute Exercise Lower Cardiovascular Stress Reactivity? Findings from a Scoping Review

Exaggerated cardiovascular reactivity to and delayed recovery from stress increase the risk of cardiovascular diseases in the future. While exercise training has been shown to attenuate stress-induced cardiovascular reactivity and enhance recovery from stress, the effects with acute exercise are less characterized. The aim of this scoping review was to explore the range and characteristics of published evidence regarding acute exercise on cardiovascular reactivity and stress recovery. The secondary objective was to highlight research gaps and implications for future research. A total of 36 articles met the review inclusion/exclusion criteria, involving 1200 participants from various age groups, fitness and health status. Blood pressure (BP) reactivity was the most measured outcome, followed by heart rate (HR) reactivity, and to some extent, heart rate variability. Overall, acute exercise particularly of the moderate-intensity aerobic type effectively reduced stress-induced BP reactivity in the general population. The effects on HR reactivity and cardiovascular recovery were inconclusive. Further research would be recommended to establish if other forms of exercise intensity or type are equally beneficial to lower exaggerated cardiovascular responses to stress. Despite methodological differences and limitations, the available evidence supports the therapeutic potential of acute exercise in addressing the ill effects of stress on cardiovascular health.

Stress and cancer: mechanisms, significance and future directions

The notion that stress and cancer are interlinked has dominated lay discourse for decades. More recent animal studies indicate that stress can substantially facilitate cancer progression through modulating most hallmarks of cancer, and molecular and systemic mechanisms mediating these effects have been elucidated. However, available clinical evidence for such deleterious effects is inconsistent, as epidemiological and stress-reducing clinical interventions have yielded mixed effects on cancer mortality. In this Review, we describe and discuss specific mediating mechanisms identified by preclinical research, and parallel clinical findings. We explain the discrepancy between preclinical and clinical outcomes, through pointing to experimental strengths leveraged by animal studies and through discussing methodological and conceptual obstacles that prevent clinical studies from reflecting the impacts of stress. We suggest approaches to circumvent such obstacles, based on targeting critical phases of cancer progression that are more likely to be stress-sensitive; pharmacologically limiting adrenergic-inflammatory responses triggered by medical procedures; and focusing on more vulnerable populations, employing personalized pharmacological and psychosocial approaches. Recent clinical trials support our hypothesis that psychological and/or pharmacological inhibition of excess adrenergic and/or inflammatory stress signalling, especially alongside cancer treatments, could save lives.

Attenuation of stress-induced cardiovascular reactivity following high-intensity interval exercise in untrained males

Exaggerated cardiovascular (CV) reactivity to stress is associated with negative cardiovascular outcomes. This study aimed to investigate the effects of acute high-intensity interval exercise (HIIE) and moderate-intensity exercise (MIE) on CV reactivity in response to a stress challenge in untrained males. Thirteen, normotensive males (age: 22.8 ± 2 years, BMI: 21.9 ± 3.6 kg/m²) underwent three conditions in counterbalanced order: HIIE (bodyweight exercises; 80-90% HRR), MIE (treadmill-jog; 55-60% HRR) and seated rest (CON) separated by 7-10 days. Thirty minutes after performing HIIE, MIE or CON, subjects underwent a 2-min cold pressor task (CPT). Blood pressure (BP) and heart rate (HR) were measured before, during, and after CPT. CV reactivity, i.e., the change in BP and HR responses were compared across conditions. Systolic BP reactivity were attenuated following HIIE (-60%, p = 0.015) and MIE (-42%, p = 0.033) compared to CON, but no differences were observed between HIIE and MIE. HR reactivity was not different across all conditions. We conclude that performing HIIE or MIE 30 minutes prior to acute stress exposure lowers BP reactivity compared to rest in untrained males. These findings highlight the potential benefits of HIIE in lowering stress-induced elevations in blood pressure.

Acute Blood Pressure Effects in Older Adults with Hypertension After Different Modalities of Exercise: An Experimental Study

This study investigated the acute blood pressure (BP) effects of different exercise modalities in older adults with hypertension. Sixty volunteers were randomly assigned (n = 15/group) into different exercise protocols: resistance, bike, water-based exercise (WE), and a control session-all for ∼45 min. Clinic BP measurements were taken before, immediately after, and 15 and 30 min after protocols. The data were analyzed by one-way analysis of variance; generalized estimating equations, following Bonferroni post hoc (p < .05). Immediately after exercise, the systolic BP (SBP) increased in all exercise protocols (resistance exercise = Δ10.3, bike exercise = Δ5.8, WE = Δ9.5 mmHg; p < .001), while the diastolic BP was not altered. Afterward, the SBP reached the value observed before exercise. In Minute 30, only WE presented a significant reduction for SBP (WE = Δ-4.6 mmHg; p < .05). This study has important clinical implications in hemodynamic safety for acute BP increases immediately after exercises, as well as, in the SBP, reduction benefits for older adults with hypertension.

Physical activity moderates the effects of daily psychosocial stressors on ambulatory blood pressure

OBJECTIVE

Previous literature has shown an inconsistent relationship between physical activity and stressor-evoked blood pressure reactivity. Use of ecological momentary assessment (EMA) may facilitate detecting such a relationship. In this study, the moderating effects of regular physical activity on the magnitude of ambulatory blood pressure (ABP) responses to psychosocial stressors experienced in daily life were examined.

METHOD

Four hundred seventy-seven healthy working adults (ages 30-54) provided ABP readings and recorded their daily experiences, using electronic diaries (ED), over 4 monitoring days. Measures of momentary Task Strain (high demand, low control) and Social Conflict (rating of recent social interaction quality) were used as indices of stressor exposure, and an accelerometry device was used to create 2 indices of physical activity: weekly average and recent (30 min prior to each ED interview). Multilevel models were used to examine the moderating between- and within-person effects of physical activity on ABP fluctuations corresponding with the momentary psychosocial stressors.

RESULTS

Weekly physical activity moderated the effects of ABP responses to Task Strain (systolic blood pressure [SBP]: p = .033; diastolic blood pressure [DBP]: p = .028) and Social Conflict (DBP: p = .020), with significant increases in SBP and DBP shown for less physically active individuals but not for more physically active individuals. Similarly, recent physical activity moderated within-person DBP responses to Task Strain (p = .025), with greater DBP increases following less active periods.

CONCLUSION

Our results demonstrate that weekly and recent physical activity may moderate the effects of ABP responses to daily psychosocial stress. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Small intra-individual variability of the pre-ejection period justifies the use of pulse transit time as approximation of the vascular transit

Background

Vascular transit time (VTT) is the propagation time of a pulse wave through an artery; it is a measure for arterial stiffness. Because reliable non-invasive VTT measurements are difficult, as an alternative we measure pulse transit time (PTT). PTT is defined as the time between the R-wave on electrocardiogram and arrival of the resulting pulse wave in a distal location measured with photoplethysmography (PPG). The time between electrical activation of the ventricles and the resulting pulse wave after opening of the aortic valve is called the pre-ejection period (PEP), a component of PTT. The aim of this study was to estimate the variability of PEP at rest, to establish how accurate PTT is as approximation of VTT.

Methods

PTT was measured and PEP was assessed with echocardiography (gold standard) in three groups of 20 volunteers: 1) a control group without cardiovascular disease aged <50 years and 2) aged >50 years, and 3) a group with cardiovascular risk factors, defined as arterial hypertension, dyslipidemia, kidney failure and diabetes mellitus.

Results

Per group, the mean PEP was: 1) 58.5 ± 13.0 ms, 2) 52.4 ± 11.9 ms, and 3) 57.6 ± 11.6 ms. However, per individual the standard deviation was much smaller, i.e. 1) 2.0–5.9 ms, 2) 2.8–5.1 ms, and 3) 1.6–12.0 ms, respectively. There was no significant difference in the mean PEP of the 3 groups (p = 0.236).

Conclusion

In conclusion, the intra-individual variability of PEP is small. A change in PTT in a person at rest is most probably the result of a change in VTT rather than of PEP. Thus, PTT at rest is an easy, non-invasive and accurate approximation of VTT for monitoring arterial stiffness.

A Role for Exercise in Attenuating Unhealthy Food Consumption in Response to Stress

It is well established that both acute and chronic stress can be detrimental to health and wellbeing by directly increasing the risk of several chronic diseases and related health problems. In addition, stress may contribute to ill-health indirectly via its downstream effects on individuals’ health-related behaviour, such as promoting the intake of unhealthy palatable foods high in fat and sugar content. This paper reviews (a) the research literature on stress-models; (b) recent research investigating stress-induced eating and (c) the potential physiological and psychological pathways contributing to stress-induced eating. Particular attention is given to (d) the role of physical exercise in attenuating acute stress, with exploration of potential mechanisms through which exercise may reduce unhealthy food and drink consumption subsequent to stressor exposure. Finally, exercise motivation is discussed as an important psychological influence over the capacity for physical exercise to attenuate unhealthy food and drink consumption after exposure to stressors. This paper aims to provide a better understanding of how physical exercise might alleviate stress-induced unhealthy food choices.

Blood pressure reactivity to mental stress is attenuated following resistance exercise in older hypertensive women

PURPOSE

This study aimed to investigate the effects of resistance exercise (RE) on autonomic control and blood pressure (BP) reactivity during mental stress (MS) in treated older hypertensive women.

METHODS

Ten older hypertensive women (age =71.1±5.5 years; body mass index =24.2±3.9; mean BP [MBP] =85.4±3.5) underwent a protocol consisting of BP and heart rate variability (HRV) output assessments at baseline and during MS, and these measurements were taken before and 60 minutes after two bouts of RE (traditional and circuit). MS was induced through a computerized 3-minute Stroop color-word test before and 1 hour after each exercise session; BP was measured every minute during MS, and HRV was monitored as a measure of cardiac autonomic control.

RESULTS

A significant effect of time on systolic BP (Δpre =17.4±12.8 versus Δpost =12.5±9.6; P=0.01), diastolic BP (Δpre =13.7±7.1 versus Δpost =8.8±4.5; P=0.01), and MBP (Δpre =14.0±7.7 versus Δpost =9.3±5.4; P<0.01) after RE was observed, with no differences between the two sessions. In addition, a significant effect of time on log-normalized low-frequency component of HRV (ms2; 5.3±0.8 pre-exercise MS versus 4.8±1.0 baseline value; P=0.023) was also observed, showing a significant change from baseline to MS before RE, but not after RE sessions. These results may be related to a lessened RE-mediated cardiac sympathetic activity during MS.

CONCLUSION

RE is an effective tool to reduce BP reactivity to MS, which could therefore be associated with an acute reduction in cardiovascular risk. This result presents relevant clinical implications, combining previous evidence that recommends this exercise modality as an important component of an exercise program designed for the older and hypertensive subjects.

The Effects of Acute Exercise on Mood, Cognition, Neurophysiology, and Neurochemical Pathways: A Review

A significant body of work has investigated the effects of acute exercise, defined as a single bout of physical activity, on mood and cognitive functions in humans. Several excellent recent reviews have summarized these findings; however, the neurobiological basis of these results has received less attention. In this review, we will first briefly summarize the cognitive and behavioral changes that occur with acute exercise in humans. We will then review the results from both human and animal model studies documenting the wide range of neurophysiological and neurochemical alterations that occur after a single bout of exercise. Finally, we will discuss the strengths, weaknesses, and missing elements in the current literature, as well as offer an acute exercise standardization protocol and provide possible goals for future research.

Water aerobics is followed by short-time and immediate systolic blood pressure reduction in overweight and obese hypertensive women

One exercise training session such as walking, running, and resistance can lead to a decrease in blood pressure in normotensive and hypertensive individuals, but few studies have investigated the effects of exercise training in an aquatic environment for overweight and obese hypertensive individuals. We aimed to assess the acute effects of a water aerobics session on blood pressure changes in pharmacologically treated overweight and obese hypertensive women. A randomized crossover study was carried out with 18 hypertensive women, 10 of them were overweight (54.4 ± 7.9 years; body mass index: 27.8 ± 1.7 kg/m(2)) and eight obese (56.4 ± 6.6 years; body mass index: 33.0 ± 2.0 kg/m(2)). The water aerobics exercise session consisted of a 45-minute training at the intensity of 70%-75% of maximum heart rate adjusted for the aquatic environment. The control group did not enter the pool and did not perform any exercise. We measured systolic blood pressure (SBP) and diastolic blood pressure (DBP) before, immediately after, and every 10 minutes up to 30 minutes after the aerobic exercise or control session. Overall (n = 18), DBP did not change after the water aerobic exercise and control session, and SBP decreased at 10 and 20 minutes postexercise compared to the control session. Among overweight women, SBP decreased at 10 and 20 minutes postexercise. In contrast, among obese women, SBP decreased only at 10 minutes postexercise. SBP variation was -2.68 mm Hg in overweight and -1.24 mm Hg in obese women. In conclusion, the water aerobics session leads to a reduction in SBP, but not in DBP, during 10 and 20 minutes postexercise recovery. Thus, it may be safely prescribed to overweight and obese women.

Stress, behavior, and biology: risk factors for cardiovascular diseases in youth

Psychological stress reactivity is associated with atherogenesis in youth. The novel hypothesis is that stress promotes atherogenic behaviors, including snacking on energy-dense food and reducing physical activity, and increases adiposity. Stress also increases systolic blood pressure cardiovascular reactivity, which also may be atherogenic. Exercise dampens stress reactivity and may be one mechanism by which it protects against the development of cardiovascular diseases.

Traditional games resulted in post-exercise hypotension and a lower cardiovascular response to the cold pressor test in healthy children

The present study aimed to verify if blood pressure (BP) reactivity could be reduced through a previous single session of active playing when compared to sedentary leisure. Sixteen pre-pubertal healthy children participated in this study. After familiarization with procedures and anthropometric evaluation, participants performed three sessions in randomized order: (1) 30 min of traditional Brazilian games (PLAY); (2) 30 min of video game playing (DDR); and (3) 30 min of watching TV (TV). Each session lasted 80 min, being 10 min of rest; 30 min of intervention activity; and 40 min of recovery. After recovery, the Cold Pressor Test (CPT) was used for the assessment of acute cardiovascular reactivity. BP was recorded at 30 s and 1 min during the CPT. Analysis of variance showed post-exercise hypotension (PEH) only after PLAY, and that systolic and diastolic BP were significantly increased in all conditions during CPT. However, the magnitude of the CPT-induced BP response was significantly less in PLAY compared to DDR and TV. The PEH observed during recovery and the reduced BP response to CPT following playing traditional games may be due its higher cardiovascular and metabolic demand as was indicated by the increased heart rate, oxygen consumption, and BP. It was concluded that BP reactivity to stress may be reduced through a previous single session of traditional games and that PEH was recorded only after this exercise form. This benefit indicates a potential role of playing strategies for cardiovascular health in childhood.

Combined exercise circuit session acutely attenuates stress-induced blood pressure reactivity in healthy adults

Objective

To investigate the blood pressure (BP) responses to cardiovascular stress test after a combined exercise circuit session at moderate intensity.

Method

Twenty individuals (10 male/10 fem; 33.4± 6.9 years; 70.2± 15.8 kg; 170.4± 11.5 cm; 22.3± 6.8% body fat) were randomized in a different days to control session with no exercise or exercise session consisting of 3 laps of the following circuit: knee extension, bench press, knee flexion, rowing in the prone position, squats, shoulder press, and 5 min of aerobic exercise at 75-85% of age-predicted maximum heart rate and/or 13 on the Borg Rating of Perceived Exertion [scale of 6 to 20]. The sets of resistance exercise consisted of 15 repetitions at ~50% of the estimated 1 repetition maximum test. Systolic blood pressure (SBP) and diastolic blood pressure (DBP) were measured at rest and during 1h of recovery in both experimental sessions. After that, blood pressure reactivity (BP_R) was evaluated using the Cold Pressor Test.

Results

During 1h of exercise recovery, there was a reduction in SBP (3-6 mmHg) and DBP (2-5 mmHg) in relation to pre-session rest (p<0.01), while this reduction was not observed in the control session. A decline in BP_R (4-7 mmHg; p<0.01) was observed 1h post-exercise session, but not in the control session. Post-exercise reductions in SBP and DBP were significantly correlated with BP_R reductions (r=0.50-0.45; p<0.05).

Conclusion

A combined exercise circuit session at moderate intensity promoted subsequent post-exercise hypotension and acutely attenuated BP_R in response to a cardiovascular stress test. In addition, the post-exercise BP reduction was correlated with BP_R attenuation in healthy adults of both genders.

Psychosocial stress and cardiovascular disease risk: the role of physical activity

Chronic stress and depression are associated with increased risk of cardiovascular disease and poorer prognosis, and physical (in)activity may be a key underlying biobehavioral mechanism. Physical activity has antidepressant effects, and physically fitter, more active individuals seem to be more biologically resilient to psychosocial stressors. This article will present data from a series of population cohort studies and laboratory-based psychophysiological studies to explore the role of physical activity as a protective factor against the effects of psychosocial stress on cardiovascular disease. These mechanisms may improve the treatment and prevention of stress-related illnesses and, thus, has important implications for public health and clinical care of high-risk patients.

A Mechanism-Based Approach to Prevention of and Therapy for Fibromyalgia

Fibromyalgia syndrome (FMS) is characterized by pain referred to deep tissues. Diagnosis and treatment of FMS are complicated by a variable coexistence with regional pain, fatigue, sleep disruption, difficulty with mentation, and depression. The widespread, deep pain of FMS can be a consequence of chronic psychological stress with autonomic dysregulation. Stress acts centrally to facilitate pain and acts peripherally, via sympathetic vasoconstriction, to establish painful muscular ischemia. FMS pain, with or without a coexistent regional pain condition, is stressful, setting up a vicious circle of reciprocal interaction. Also, stress interacts reciprocally with systems of control over depression, mentation, and sleep, establishing FMS as a multiple-system disorder. Thus, stress and the ischemic pain it generates are fundamental to the multiple disorders of FMS, and a therapeutic procedure that attenuates stress and peripheral vasoconstriction should be highly beneficial for FMS. Physical exercise has been shown to counteract peripheral vasoconstriction and to attenuate stress, depression, and fatigue and improve mentation and sleep quality. Thus, exercise can interrupt the reciprocal interactions between psychological stress and each of the multiple-system disorders of FMS. The large literature supporting these conclusions indicates that exercise should be considered strongly as a first-line approach to FMS therapy.

Effect of preceding exercise on cerebral and splanchnic vascular responses to mental task

Background

To investigate the effect of preceding acute exercise on the peripheral vascular response to a mental task, we measured splanchnic and cerebral blood flow responses to performing a mental task after exercise and resting.

Methods

In the exercise trial, 11 males exercised for 30 min on a cycle ergometer with a workload set at 70% of the age-predicted maximal heart rate for each individual. After a 15-min recovery period, the subjects rested for 5 min for pre-task baseline measurement and then performed mental arithmetic for 5 min followed by 5 min of post-task measurement. In the resting trial, they rested for 45 min and pre-task baseline data was obtained for 5 min. Then mental arithmetic was performed for 5 min followed by post-task measurement. We measured the mean blood velocity in the middle cerebral artery and superior mesenteric artery and the mean arterial pressure.

Results

Mean arterial pressure and mean blood velocity in the middle cerebral artery were significantly higher than the baseline during mental arithmetic in both exercise and resting trials. Mean blood velocity in the middle cerebral artery during mental arithmetic was greater in the control trial than the exercise trial. Mean blood velocity in the superior mesenteric artery showed no significant change during mental arithmetic from baseline in both trials.

Conclusion

These results suggest that acute exercise can moderate the increase in cerebral blood flow induced by a mental task.

Excess heart rate and systolic blood pressure during psychological stress in relation to metabolic demand in adolescents

Cardiovascular responses during exercise are matched to the increased metabolic demand, but this may not be the case during psychological stress. No studies to date have tested this hypothesis in youth. Fifty-four youth, ages 13-16 years completed two visits. Heart rate (HR), systolic blood pressure (SBP), and oxygen (O(2)) consumption were measured during a graded exercise test on one day and during psychological stress reactivity (star tracing, speech) on another day. Predicted HR and SBP values during psychological stress were calculated based on HR-O(2) and SBP-O(2) relationships calculated during graded exercise. At a given O(2) consumption, actual HR was greater (p<0.02) than predicted for all stress tasks. Actual SBP was greater (p<0.001) than predicted for all stress tasks. This was the first study to demonstrate that cardiovascular responses were in excess of what would be expected based on metabolic demand in youth.

Hemodynamic mechanisms of the attenuated blood pressure response to mental stress after a single bout of maximal dynamic exercise in healthy subjects

To determine the hemodynamic mechanisms responsible for the attenuated blood pressure response to mental stress after exercise, 26 healthy sedentary individuals (age 29 ± 8 years) underwent the Stroop color-word test before and 60 min after a bout of maximal dynamic exercise on a treadmill. A subgroup (N = 11) underwent a time-control experiment without exercise. Blood pressure was continuously and noninvasively recorded by infrared finger photoplethysmography. Stroke volume was derived from pressure signals, and cardiac output and peripheral vascular resistance were calculated. Perceived mental stress scores were comparable between mental stress tests both in the exercise (P = 0.96) and control (P = 0.24) experiments. After exercise, the systolic blood pressure response to mental stress was attenuated (pre: 10 ± 13 vs post: 6 ± 7 mmHg; P < 0.01) along with lower values of systolic blood pressure (pre: 129 ± 3 vs post: 125 ± 3 mmHg; P < 0.05), stroke volume (pre: 89.4 ± 3.5 vs post: 76.8 ± 3.8 mL; P < 0.05), and cardiac output (pre: 7.00 ± 0.30 vs post: 6.51 ± 0.36 L/min; P < 0.05). Except for heart rate, the hemodynamic responses and the mean values during the two mental stress tests in the control experiment were similar (P > 0.05). In conclusion, a single bout of maximal dynamic exercise attenuates the blood pressure response to mental stress in healthy subjects, along with lower stroke volume and cardiac output, denoting an acute modulatory action of exercise on the central hemodynamic response to mental stress.

The role of obesity, salt and exercise on blood pressure in children and adolescents

The increasing trends of blood pressure (BP) in children and adolescents pose great concern for the burden of hypertension-related cardiovascular disease. Although primary hypertension in childhood is commonly associated with obesity, it seems that other factors, such as dietary sodium and exercise, also influence BP levels in children and adolescents. Several studies support that sympathetic nervous system imbalance, impairment of the physiological mechanism of pressure natriuresis, hyperinsulinemia and early vascular changes are involved in the mechanisms causing elevated BP in obese children and adolescents. Under the current evidence on the association of salt intake and BP, dietary sodium restriction appears to be a rational step in the prevention of hypertension in genetically predisposed children and adolescents. Finally, interventional studies show that regular aerobic exercise can significantly reduce BP and restore vascular changes in obese with hypertensive pediatric patients. This article aims to summarize previous studies on the role of obesity, salt intake and exercise on BP in children and adolescents.

Exercise lowers blood pressure in university professors during subsequent teaching and sleeping hours

BACKGROUND

University professors are subjected to psychological stress that contributes to blood pressure (BP) reactivity and development of hypertension. The purpose of this study was to investigate the effects of exercise on BP in university professors during teaching and sleeping hours.

METHODS

Twelve normotensive professors (42.2 ± 10.8 years, 74.2 ± 11.2 kg, 172.8 ± 10.4 cm, 20.1% ± 6.7% body fat) randomly underwent control (CONT) and exercise (EX30) sessions before initiating their daily activities. EX30 consisted of 30 minutes of cycling at 80%-85% of heart rate reserve. Ambulatory BP was monitored for 24 hours following both sessions.

RESULTS

BP increased in comparison with pre-session resting values during teaching after CONT (P < 0.05) but not after EX30. Systolic, diastolic, and mean arterial BP showed a more pronounced nocturnal dip following EX30 (approximately -14.7, -12.7, and -9.6 mmHg, respectively) when compared with CONT (approximately -6, -5 and -3 mmHg).

CONCLUSION

Exercise induced a BP reduction in university professors, with the main effects being observed during subsequent teaching and sleeping hours.

The moderating effect of physical activity on cardiovascular reactivity following single fat feedings

This experiment examined the effects of consuming a high-fat meal on cardiovascular reactivity and the ability of exercise to act as a moderator between dietary fat consumption and cardiovascular reactivity. Forty healthy, college-age students were randomly assigned to one of four experimental groups: (1) low-fat meal, no exercise; (2) low-fat meal, postprandial exercise; (3) high-fat meal, no exercise; and (4) high-fat meal, postprandial exercise. To induce stress, all participants performed a public speaking task, while heart rate and blood pressure reactivity were measured. Multilevel analyses revealed that consuming a high-fat meal led to heightened mean arterial pressure reactivity. Acute high-intensity exercise resulted in attenuated heart rate and mean arterial pressure reactivity. The results of this study offer insight into how diet and exercise may influence cardiovascular reactivity, which is a key determinant of cardiovascular disease.

Hypotensive response after water-walking and land-walking exercise sessions in healthy trained and untrained women

Background:

The aim of this study was to compare post-exercise hypotension after acute sessions of water-walking and land-walking in healthy trained and untrained women.

Methods:

Twenty-three untrained (n = 12) and trained (n = 11) normotensive women performed two walking sessions in water and on land at 40% of peak VO₂ for 45 minutes. Systolic and diastolic blood pressure and mean arterial pressure were measured 15, 30, 45, and 60 minutes after the exercise sessions.

Results:

No differences were found between the groups for age and anthropometric parameters, but peak VO₂ for the trained women (45 ± 8 mL/kg/minute) was higher than for the untrained women (31 ± 3 mL/kg/minute). No differences were found between the groups with regard to systolic and diastolic blood pressure and mean arterial pressure after water immersion. The heart rate in the trained group (62 ± 3 beats per minute [bpm]) was significantly lower (P < 0.05) than in the untrained group (72 ± 4 bpm) on land, and after water immersion, this difference disappeared (58 ± 5 bpm in the trained women and 66 ± 5 bpm in the untrained women). Sixty minutes after water-walking, systolic blood pressure (108 ± 8 mmHg vs 97 ± 3 mmHg), diastolic blood pressure (69 ± 5 mmHg vs 62 ± 5 mmHg), and mean arterial pressure (82 ± 6 mmHg vs 74 ± 4 mmHg) decreased significantly with rest in the untrained group, and no differences were found after land-walking. In the trained group, significant (P < 0.05) differences were found only for systolic blood pressure (110 ± 9 mmHg vs 100 ± 9 mmHg) after 60 minutes of water-walking; decreases in systolic blood pressure were found after 45 minutes (99 ± 7 mmHg) and 60 minutes (99 ± 6 mmHg) compared with rest (107 ± 5 mmHg) after land-walking.

Conclusion:

Single water-walking and land-walking sessions induced important hypotension following exercise. Additionally, walking performed in chest-deep water has a better effect on exercise-induced hypotension in untrained healthy women than walking at a similar intensity on land.

Impaired hemodynamic response to mental stress in subjects with prehypertension is improved after a single bout of maximal dynamic exercise

INTRODUCTION

High blood pressure during mental stress in subjects with prehypertension is associated with blunted vasodilation in skeletal muscles, which might be improved by an acute bout of exercise.

OBJECTIVE

To investigate the hemodynamic responses to mental stress before and after a bout of exercise in subjects with prehypertension.

METHOD

Eighteen subjects with prehypertension and 16 with normotension underwent a mental stress test before and after a maximal cardiopulmonary exercise test on a treadmill. Blood pressure was measured by auscultation, and forearm blood flow was measured by venous occlusion plethysmography; from these measurements, the vascular conductance was calculated.

RESULTS

Subjects with prehypertension had a higher mean blood pressure during mental stress (prehypertension 112 ± 2 vs. normotension 101 ± 3 mm Hg, p<0.05), and their vascular conductance did not increase (baseline 0.025 ± 0.004 vs. mental stress 0.022 ± 0.003 a.u., p.0.05). After the exercise bout, the mean blood pressure during mental stress was lower in subjects with prehypertension (before exercise 112 ± 2 vs. after exercise 107 ± 2 mm Hg, p<0.05), and vascular conductance increased (baseline 0.011 ± 0.001 vs. mental stress 0.024 ± 0.004 a.u., p<0.05).

CONCLUSION

Subjects with prehypertension had elevated blood pressure and a blunted vasodilator response during mental stress, but their blood pressure was attenuated and their vasodilator response was normalized after a single bout of maximal dynamic exercise.

Effect of a simulated active commute to school on cardiovascular stress reactivity

PURPOSE

Stress-induced cardiovascular reactivity is associated with the pathogenesis of cardiovascular disease. This study tested whether a simulated active commute to school dampened cardiovascular reactivity to a cognitive stressor typical to what children might experience during school.

METHODS

Forty children (20 girls and 20 boys) aged 10-14 yr were randomly assigned to simulated sedentary drive-to-school or active-commute (walking) groups. The walking group completed a self-paced 1.6-km walk on a treadmill while images from a real 1.6-km walk through a pleasant neighborhood that finished at a school were projected in front of them. The drive-to-school group sat in a chair and watched the same slideshow of images of the neighborhood environment. Standardized residualized gain scores of cardiovascular reactivity during a cognitive stressor, the Stroop task, were calculated and used as dependent variables.

RESULTS

Children in the walking group self-selected a walking intensity of 60.6% +/- 1.6% HRmax and covered the 1.6-km distance in 21.5 +/- 0.5 min. Children in the walking group had lower HR (2 +/- 1 vs 11 +/- 1 bpm, P < 0.001), systolic blood pressure (4 +/- 1 vs 12 +/- 1 mm Hg, P < 0.001), pulse pressure (-4 +/- 1 vs 6 +/- 1 mm Hg, P < 0.001), and perceived stress (1.4 +/- 0.1 vs 3.0 +/- 0.1 cm, P < 0.001) reactivities to cognitive stress than the control group.

CONCLUSIONS

Active commuting to school may dampen cardiovascular reactivity and perceived stress when confronted with stressful cognitive challenges during the school day. This may help reduce the risk for cardiovascular disease later in life.

Adrenergic dysregulation and pain with and without acute beta-blockade in women with fibromyalgia and temporomandibular disorder

In patients with fibromyalgia syndrome (FMS) and temporomandibular disorder (TMD), stress and pain may chronically enhance sympathetic activity, altering cardiovascular responses and worsening pain. This study examined cardiovascular, epinephrine (EPI), norepinephrine (NE), cortisol and clinical pain responses in 54 female patients with these disorders and 34 controls. In a subsample of 10 FMS, 10 TMD patients and 16 controls, using a counterbalanced, double-blind, crossover design, the same responses were assessed after intravenous administration of low dose propranolol vs placebo. Testing included baseline, postural, speech and ischemic pain stressors. FMS patients showed lesser heart rate (HR) increases to posture challenge but greater blood pressure (BP) increases to postural and speech tasks than controls, as well as higher overall BP and greater total vascular resistance (TVR) than TMDs or controls. TMDs showed higher overall cardiac output and lower TVR than controls. Both FMS and TMD groups showed lower baseline NE than controls, and TMDs showed lower overall EPI and NE levels. Group differences in HR, EPI and NE were abolished after propranolol although BP, CO and TVR differences persisted. In both FMS and TMD, the number of painful body sites and ratings of total clinical pain obtained 4 times during each session were significantly lower after beta-blockade vs placebo.

PERSPECTIVE

These findings support the hypothesis that both FMS and TMD may frequently involve dysregulation of beta-adrenergic activity that contributes to altered cardiovascular and catecholamine responses and to severity of clinical pain. Acute treatment with low-dose propranolol led to short-term improvement in all these domains.

Cardiac autonomic function and baroreflex changes following 4 weeks of resistance versus aerobic training in individuals with pre-hypertension

AIM

Cardiac autonomic modulation and baroreflex sensitivity (BRS) are altered in individuals with hypertension. Aerobic exercise (AE) training has been shown to improve both measures, yet little is known about the effects of resistance exercise (RE). The purpose of this study was to examine the heart rate variability (HRV) and BRS following 4 weeks of resistance or aerobic training in a population with borderline high blood pressure (BP).

METHODS

Twenty-nine mild hypertensives were recruited and randomly assigned to 4 weeks of RE or AE training. Before and after training, resting measures of HRV frequencies and BRS were obtained.

RESULTS

There was a significant decrease in resting systolic BP for both exercise training modes (RE 136 +/- 3.0 pre- to 132 +/- 3.4 post-training vs. AE 142 +/- 4.0 pre- to 137 +/- 3.6 mmHg post-training, P = 0.019). Diastolic BP decreased significantly following both exercise training modes (RE 78 +/- 1.31 pre to 74 +/- 1.1 post vs. AE 80 +/- 1.7 pre to 77 +/- 1.6 mmHg post, P = 0.002). A significant time by training mode interaction for low frequency : high frequency (HF) ratio (P = 0.017) with AE decreasing the ratio (275.21 +/- 67.28 to 161.26 +/- 61.49) and RE increasing this ratio (143.73 +/- 65.00 to 227.83 +/- 59.41). Natural log-transformed (ln) HRV values showed a time-by-training mode interaction for ln HF (P = 0.05) as ln HF increased (4.7 +/- 0.38 to 5.4 +/- 0.35 ms(2)) following AE and decreased (5.98 +/- 0.37 to 5.76 +/- 0.42 ms(2)) following RE. BRS increased following aerobic training and decreased after resistance training (6.74 +/- 1.2 to 7.94 +/- 1.3 and 10.44 +/- 1.2 to 9.1 +/- 1.2 ms mmHg(-1) respectively, P = 0.021).

CONCLUSIONS

Aerobic exercise improved the autonomic nervous system (increasing vagal tone, reducing sympathovagal balance while increasing BRS) while RE showed no improvements in cardiac autonomic tone and decreased BRS.

Sport therapy for hypertension: why, how, and how much?

Exercise may prevent or reduce the effects of metabolic and cardiovascular diseases, including arterial hypertension. Both acute and chronic exercise, alone or combined with lifestyle modifications, decrease blood pressure and avoid or reduce the need for pharmacologic therapy in patients with hypertension. The hypotensive effect of exercise is observed in a large percentage of subjects, with differences due to age, sex, race, health conditions, parental history, and genetic factors. Exercise regulates autonomic nervous system activity, increases shear stress, improves nitric oxide production in endothelial cells and its bioavailability for vascular smooth muscle, up-regulates antioxidant enzymes. Endurance training is primarily effective, and resistance training can be combined with it. Low-to-moderate intensity training in sedentary patients with hypertension is necessary, and tailored programs make exercise safe and effective also in special populations. Supervised or home-based exercise programs allow a nonpharmacological reduction of hypertension and reduce risk factors, with possible beneficial effects on cardiovascular morbidity.

Hypotensive effects of exercise performed around anaerobic threshold in type 2 diabetic patients

AIM

To verify the occurrence of post-exercise hypotension (PEH) in type 2 diabetics (DM(2)) and the effects of exercise intensity on post-exercise blood pressure (BP).

METHODS

Eleven men and women with DM(2) (58.5+/-10.2 years; 160+/-0.1cm; 80.6+/-13.5kg; 31.2+/-3.8kg/m(2), 19+/-3.2mLkgmin(-1) of VO(2max), 155.0+/-39.2mgdL(-1) of fasting blood glucose and 126+/-10/75+/-7mmHg of resting BP) performed an incremental test (IT) for cardiovascular evaluation and anaerobic threshold (AT) determination. Then, participants randomly underwent 2 exercise sessions (90% and 110% AT) and a control session (CON). In all sessions, BP was measured at resting, during 20min of exercise/control and at each 15min through 120min of post-exercise recovery (R15-R120).

RESULTS

The mean results of systolic BP (SBP)/diastolic BP (DBP) over the 120min of recovery were 125+/-16/76+/-7mmHg, 122+/-13/75+/-6mmHg and 129+/-16/78+/-7mmHg, respectively for 90%, 110% and CON. Significant reductions of SBP occurred after 90% (R15-R45) and 110% (R15-R90), while only after 110% there were reductions of DBP (R15, R45) and MAP (R15, R45, R75, R90, R105).

CONCLUSIONS

Both exercise intensities evoked reductions in SBP while DBP and MAP were reduced only after 110%. Despite the higher intensity exercise to be more effective in promoting BP reductions, we suggest caution while prescribing exercise for DM(2).

Emotional stress and the risk to develop hypertensive diseases in pregnancy

OBJECTIVE

Cardiovascular diseases are strongly influenced by stress and do share several risk factors with hypertensive diseases in pregnancy (HDP). The aim of the study is to investigate the correlation between emotional stress during pregnancy and the risk for HDP.

METHODS

A self-administered questionnaire comprising obstetrical and psychosocial questions was completed by 725 patients and 880 controls matched for age, parity, nationality, and educational level.

RESULTS

Emotional stress during pregnancy was associated with a 1.6-fold increased risk for HDP.

CONCLUSION

Psychosocial interventions to reduce emotional stress during pregnancy may help to decrease the risk to develop HDP.

Aerobic exercise intensity and time of stressor administration influence cardiovascular responses to psychological stress

This study examined cardiovascular responses as a function of time following exercise in which participants were exposed to a laboratory stressor. Ninety (42 women) young (18-35 years old) nonsmoking normotensive participants engaged in 30 min of high and low intensity (75-80% and 50-55% VO(2) max) aerobic exercise and a sedentary control condition. Participants were randomly assigned to a laboratory stressor 5, 30, or 60 min following the exercise bout. Results indicate that low and high intensity exercise significantly reduce heart rate (HR) and systolic and diastolic blood pressure reactivity and HR recovery values. An inverse relationship between intensity of exercise and subsequent cardiovascular reactivity was found. These findings suggest attenuated stress responses following acute exercise depend both on exercise intensity and the time of exposure to psychological stress following exercise.

Tai Chi Chih Acutely Decreases Sympathetic Nervous System Activity in Older Adults

BACKGROUND

Aging is associated with increases of sympathetic nervous system activation implicated in the onset of hypertension and cardiovascular disease. The purpose of this study was to examine whether the practice of Tai Chi Chih (TCC), a movement-based relaxation practice, would acutely promote decreases of sympathetic activity in elderly persons.

METHOD

The sample included two groups of older men and women (age > or = 60 years): TCC practitioners (n = 19) and TCC-naïve participants (n = 13). Participants were recruited after completing a 25-week randomized trial of TCC or health education. TCC practitioners performed TCC for 20 minutes, and TCC-naïve participants passively rested. Preejection period, blood pressure, and heart rate were measured before and after the task. A subsample (n = 8) returned for a second evaluation and performed videotape-guided stretching for 20 minutes to evaluate the effects of slow-moving physical activity on sympathetic activity.

RESULTS

Results showed that TCC performance significantly decreased sympathetic activity as indexed by preejection period (p =.01). In contrast, there was no change in preejection period following passive rest or slow-moving physical activity. Neither blood pressure nor heart rate changed after TCC performance.

DISCUSSION

This study is the first to our knowledge to assess the acute effects of TCC practice on sympathetic activity in older adults. TCC performance led to acute decreases in sympathetic activity, which could not be explained by physical activity alone. Further study is needed to determine whether the acute salutary effects of TCC on autonomic functioning are sustained with ongoing practice in older adults.

The effects of exercise on haemodynamic function in relation to the familial hypertension risk model

Offspring hypertensives are characterized by a hyperactive sympathetic nervous system and other early cardiovascular abnormalities that increase the risk of developing hypertension. A physically active lifestyle is associated with a lower risk of hypertension, although the mechanisms are incompletely understood and likely to be multifactorial. One aspect that has received little attention is the interaction of exercise with familial hypertension risk. The present review examines the effects of exercise on haemodynamic function in relation to the familial hypertension risk model. Paradoxically, exercise may be viewed as potent stressor to the cardiovascular system, although recent studies are beginning to show that cardiovascular adaptations, primarily mediated by changes in sympatho-vagal balance, following both acute and chronic exercise may be particularly important for individuals with familial risk of hypertension. Future studies that focus on inflammatory, metabolic, and genetic pathways may uncover further beneficial effects of exercise in relation to familial risk.

The anti-hypertensive effects of exercise: integrating acute and chronic mechanisms

It is anticipated that hypertension will afflict up to a third of the worldwide population by the year 2025. Therefore, cost-effective treatment strategies are essential to control this disease. Exercise has been associated with anti-hypertensive benefits, but despite extensive research the optimal exercise dose (training frequency, intensity and time) required to lower blood pressure and maintain normotensive status remains unclear. This article explores the interrelationships between acute and chronic mechanisms that have been linked to the anti-hypertensive benefits of exercise and proposes that the optimal exercise dosage may depend on the interplay between these mechanisms and the effects of exercise on independent risk markers of hypertension. Therefore, the correct exercise dose for the treatment of hypertension should be prescribed on an individual basis. Future work should examine post-exercise hypotension effects in relation to exercise training in hypertensive populations and both acute and longitudinal training studies should be conducted that incorporate independent risk factors of hypertension as co-variables into their analysis on blood pressure effects.

Acute exercise reduces vascular reactivity to mental challenge in offspring of hypertensive families

OBJECTIVE

To examine the effects of acute exercise on cardiac and vascular responses to mental challenge in males at risk of hypertension.

DESIGN

A within-subjects, counterbalanced design.

PARTICIPANTS

Normotensive, healthy males with (n = 22) and without (n = 8) family history of hypertension.

METHOD

A moderately stressful behavioural task was performed for 10 min after 20 min of moderate intensity cycle ergometry exercise, and on a separate occasion after an attentional control task. The blood pressure, heart rate, cardiac output, stroke volume, forearm blood flow, forearm vascular resistance, and total peripheral resistance were measured at rest, during the task, and at recovery. Stress reactivity was defined as the difference in values between the task and the baseline.

RESULTS

An enhanced peripheral vasodilatation response to the Stroop task was observed in men with familial risk of hypertension compared with the control group. However, this enhanced response was significantly blunted in offspring hypertensive participants following an acute bout of exercise so that differences in the vasodilatation response were no longer observed in comparison with men without familial risk of hypertension. The post-exercise heart rate reactivity in comparison with the control session was also significantly blunted in both groups (P < 0.05).

CONCLUSION

Acute exercise may be an important intervention strategy to reduce the impact of cardiovascular hyper-reactivity on disease progression in males with familial risk of hypertension.

Effects of a brisk walk on blood pressure responses to the Stroop, a speech task and a smoking cue among temporarily abstinent smokers

A review and meta-analysis by Hamer et al. (2006) showed that a single session of exercise can attenuate post-exercise blood pressure (BP) responses to stress, but no studies examined the effects among smokers or with brisk walking. Healthy volunteers (n=60), averaging 28 years of age and smoking 15 cigarettes daily, abstained from smoking for 2 h before being randomly assigned to a 15-min brisk semi-self-paced walk or passive control condition. Subject characteristics, typical smoking cue-elicited cravings and BP were assessed at baseline. After each condition, BP was assessed before and after three psycho-social stressors were carried out: (1) computerised Stroop word-colour interference task, (2) speech task and (3) only handling a lit cigarette. A two-way mixed ANCOVA (controlling for baseline) revealed a significant overall interaction effect for time by condition for both systolic blood pressure (SBP) and diastolic blood pressure (DBP). Univariate ANCOVAs (to compare between-groups post-stressor BP, controlling for pre-stressor BP) revealed that exercise attenuated systolic BP and diastolic BP responses to the Stroop and speech tasks and SBP to the lit cigarette equivalent to an attenuated SBP and DBP of up to 3.8 mmHg. Post-exercise attenuation effects were moderated by resting blood pressure and self-reported smoking cue-elicited craving. Effects were strongest among those with higher blood pressure and smokers who reported typically stronger cravings when faced with smoking cues. Blood pressure responses to the lit cigarette were not associated with responses to the Stroop and speech task. A self-paced 15-min walk can reduce smokers' SBP and DBP responses to stress, of a magnitude similar on average to non-smokers.

Exercise and Psychobiological Processes

Interventions that reduce the magnitude of psychobiological responses are justified, at least in part, by the notion that exaggerated responses to stress can have detrimental effects on health. The biological processes underlying the association between stress and coronary heart disease (CHD) are thought to involve haemodynamic, neuroendocrine, inflammatory and haemostatic pathways. One of the many recognised benefits of exercise is in buffering physiological responses to psychosocial stressors, which is thought to be partly mediated by sympatho-inhibitory mechanisms, although other potentially important psychobiological processes such as inflammatory, neuroendocrine and haemostatic pathways have gained little attention. Thus, the present review focuses on the role of exercise in buffering psychobiological processes, particularly in relation to pathways that are directly relevant for reducing CHD risk. There are inconsistencies in the literature regarding the effects of exercise on cardiovascular responses to stressors, which may in part be accounted for by differences in experimental design, characteristics of participants, inadequate assessment of physical fitness, and the confounding effects of acute exercise. However, new emerging evidence suggests that exercise promotes an anti-inflammatory environment and increases tissue sensitivity to glucocorticoids, which may have implications for the effects of exercise on stress-induced inflammatory pathways. Future work should focus on the efficacy of exercise for promoting anti-inflammatory pathways in relation to psychosocial stress.

The effect of acute aerobic exercise on stress related blood pressure responses: a systematic review and meta-analysis

The beneficial impact of regular exercise on cardiovascular health is partly mediated by psychobiological mechanisms. However, the effect of acute exercise on psychobiological responses is unclear. Thus, we performed a systematic review of randomised controlled trials (RCTs) that examined the effect of acute aerobic exercise on blood pressure (BP) responses (the change from baseline to stress) to psychosocial laboratory tasks. Fifteen RCTs met inclusion criteria of which ten demonstrated significant reductions in post-exercise stress related BP responses compared with control (mean effect sizes for systolic and diastolic BP, 0.38 and 0.40). Studies involving greater exercise doses tended to show larger effects, with the minimum dose to show a significant effect being 30 min at 50% VO2max. No other moderators emerged from the examination of participant characteristics, research designs and stressor characteristics. In conclusion, an acute bout of aerobic exercise appears to have a significant impact on the BP response to a psychosocial stressor.

Exercise intensity alters postexercise hypotension

OBJECTIVE

Blood pressure (BP) is immediately lowered after a session of dynamic exercise, e.g. postexercise hypotension (PEH). The optimal exercise intensity needed to evoke PEH has not been established. We examined the effect of light (LITE) and moderate (MOD) exercise intensity on PEH.

DESIGN

Subjects were 49 men (mean +/- SEM, 43.8 +/- 1.4 years) with high normal to stage 1 hypertension (145.0 +/- 1.5/85.8 +/- 1.1 mmHg). Men randomly completed three blinded experiments: a control session and two cycle exercise bouts, one at 40% (LITE) and the other at 60% (MOD) of maximal oxygen consumption.

METHODS

Experiments began with a baseline period and were conducted at the same time of day and separated by >/= 2 days. Subjects wore an ambulatory BP monitor after the experiments. Repeated measure analysis of variance (ANOVA) tested if BP and heart rate differed over time and between experimental conditions. Multivariate regression tested factors related to the BP response.

RESULTS

For 9 h after all experiments, average awake systolic blood pressure (SBP) increased and diastolic blood pressure (DBP) decreased compared with baseline (P < 0.001). Average awake SBP increased up to 6.9 mmHg less (P < 0.001) and DBP decreased 2.6 mmHg more (P < 0.05) after exercise versus control. For 5 h, PEH was greater after MOD; but over the course of 9 h, LITE was as effective as MOD in eliciting PEH. Baseline BP was the primary factor explaining the BP response (beta = -0.434 to -0.718, r = 0.096-0.295).

CONCLUSIONS

LITE and MOD evoked PEH throughout the daytime hours. Lower intensity dynamic exercise such as walking, contributes to BP control in men with hypertension.

Short- and long-term effects of a single bout of exercise on heart rate variability: comparison between constant and interval training exercises

Heart rate variability (HRV) was assessed during the short- (within 1 h) and long- (within 48 h) term recovery following a single bout of either constant (CST) or interval training (SWEET) exercise performed at the same total physical work [9.4 (0.3) kJ kg(-1)]. R-R intervals, systolic (SAP) and diastolic (DAP) arterial pressures were recorded in supine and upright positions before and 1, 24 and 48 h after the termination of the exercises in ten male subjects [mean (SEM), age 24.6 (0.6) years, height 177.2 (1.1) cm and body mass 68.5 (0.9) kg]. The parameters were also recorded in the supine position during the first 20 min following the end of the exercise. Spectral analysis parameters of HRV [total (TP), low- (LF), and high- (HF) frequency power, and LF/TP, HF/TP and LF/HF ratios] were determined over 5 min during each phase. Except for higher HF values in both supine and upright positions during the first hour following CST compared with SWEET, cardiovascular and HRV analysis responses were of the same magnitude after their termination. R-R intervals, TP, and HF/TP were significantly decreased while LF/TP and LF/HF were significantly increased during the early recovery, when compared with control values. This could be a response to the significant decrease in SAP and DAP at this time. Twenty-four and 48 h after the end of the exercise, HRV parameters were at the same levels as before exercises in the supine posture, but a persistent tachycardia continued to be observed in the upright posture, together with reduced TP values, showing that cardiovascular functions were still disturbed. The short-term HRV recovery seemed dependent on the type of exercise, contrary to the long-term recovery.

Shingles Immunity and Health Functioning in the Elderly: Tai Chi Chih as a Behavioral Treatment

Both the incidence and severity of herpes zoster (HZ) or shingles increase markedly with increasing age in association with a decline in varicella zoster virus (VZV)-specific immunity. Considerable evidence shows that behavioral stressors, prevalent in older adults, correlate with impairments of cellular immunity. Moreover, the presence of depressive symptoms in older adults is associated with declines in VZV-responder cell frequency (VZV-RCF), an immunological marker of shingles risk. In this review, we discuss recent findings that administration of a relaxation response-based intervention, tai chi chih (TCC), results in improvements in health functioning and immunity to VZV in older adults as compared with a control group. TCC is a slow moving meditation consisting of 20 separate standardized movements which can be readily used in elderly and medically compromised individuals. TCC offers standardized training and practice schedules, lending an important advantage over prior relaxation response-based therapies. Focus on older adults at increased risk for HZ and assay of VZV-specific immunity have implications for understanding the impact of behavioral factors and a behavioral intervention on a clinically relevant end-point and on the response of the immune system to infectious pathogens.

Exercício físico e o controle da pressão arterial

O exercício físico provoca uma série de respostas fisiológicas, resultantes de adaptações autonômicas e hemodinâmicas que vão influenciar o sistema cardiovascular. Diversos estudos demonstraram o seu efeito benéfico sobre a pressão arterial. Sendo a hipertensão arterial sistêmica uma entidade de alta prevalência e elevada morbimortalidade na população, o exercício físico tem importante papel como elemento não medicamentoso para o seu controle ou como adjuvante ao tratamento farmacológico.