Aerobic exercise reduces levels of cardiovascular and sympathoadrenal responses to mental stress in subjects without prior evidence of myocardial ischemia

Exercise training improves blood pressure reactivity to stress: a systematic review and meta-analysis

Blood pressure (BP) reactivity to stress is associated with cardiovascular events and the incidence of hypertension, therefore, tolerance to stressors is important for better management of cardiovascular risks. Exercise training is among the strategies that have been investigated as blunting the peak response to stressors, however, its efficacy is poorly explored. The aim was to explore the effects of exercise training (at least four weeks) on BP responses to stressor tasks in adults. A systematic review was performed in five electronic databases (MEDLINE, LILACS, EMBASE, SPORTDiscus, and PsycInfo). Twenty-three studies and one conference abstract was included in the qualitative analysis, totaling 1121 individuals, and k = 17 and 695 individuals in the meta-analysis. Favorable results (random-effects) for exercise training were found, with attenuated peak responses in systolic (standardized mean difference (SMD) = -0.34 [-0.56; -0.11], representing average reductions of 2.5 ± 3.6 mmHg) and null effects on diastolic BP (SMD = -0.20 [-0.54; 0.14], representing average reductions of 2.0 ± 3.5 mmHg). The analysis removing outliers' studies improved the effects for diastolic (SMD = -0.21 [-0.38; -0.05]) but not systolic BP (SMD = -0.33 [-0.53; -0.13]). In conclusion, exercise training seems to lower stress-related BP reactivity, therefore has the potential to improve patients' ability to better respond to stressful situations.

Before and during the COVID-19 Pandemic, Physical Fitness Association with Mental Health among Higher Education Students: A Multi-Group Analysis Model

The coronavirus disease 2019 (COVID-19) pandemic, caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), created a significant problem people's health around the world. The mental and physical health of entire populations has been negatively impacted due to the introduction of several restriction methods. Maintaining a specific physical activity and fitness level is crucial given the pandemic situation. The connection between physical fitness and mental health has recently received growing attention. In contrast to the message from physiological research, which lauds the general benefits of fitness for physical health, the corresponding psychological literature reveals a more complex relationship. This paper outlines the research evidence, focusing on the relationship between physical fitness and depression, anxiety, and stress before and during the COVID-19 pandemic. Data were obtained from 390 higher education students (measuring their perception before and during the pandemic). They were analyzed by a structural equation modeling multi-group analysis to detect the variance in the test relationship before and during the COVID-19 pandemic. Theoretical and empirical implications are also discussed.

A mathematical model for predicting cardiovascular responses at rest and during exercise in demanding environmental conditions

The present research describes the development and validation of a cardiovascular model (CVR Model) for use in conjunction with advanced thermophysiological models, where usually only a total cardiac output is estimated. The CVR Model detailed herein estimates cardio-dynamic parameters (changes in cardiac output, stroke volume, and heart rate), regional blood flow, and muscle oxygen extraction, in response to rest and physical workloads, across a range of ages and aerobic fitness levels, as well as during exposure to heat, dehydration, and altitude. The model development strategy was to first establish basic resting and exercise predictions for cardio-dynamic parameters in an "ideal" environment (cool, sea level, and hydrated person). This basic model was then advanced for increasing levels of altitude, heat strain, and dehydration, using meta-analysis and reaggregation of published data. Using the estimated altitude- and heat-induced changes in maximum oxygen extraction and maximum cardiac output, the decline in maximum oxygen consumption at high altitude and in the heat was also modeled. A validation of predicted cardiovascular strain using heart rate was conducted using a dataset of 101 heterogeneous individuals (1,371 data points) during rest and exercise in the heat and at altitude, demonstrating that the CVR Model performs well (R² = 0.82-0.84) in predicting cardiovascular strain, particularly at a group mean level (R² = 0.97). The development of the CVR Model is aimed at providing the Fiala thermal Physiology & Comfort (FPC) Model and other complex thermophysiological models with improved estimations of cardiac strain and exercise tolerance, across a range of individuals during acute exposure to environmental stressors.NEW & NOTEWORTHY The present research promotes the adaption of thermophysiological modeling to the estimation of cardiovascular strain in individuals exercising under acute environmental stress. Integration with advanced models of human thermoregulation opens doors for detailed numerical analysis of athletes' performance and physiology during exercise, occupational safety, and individual work tolerability. The research provides a simple-to-validate metric of cardiovascular function (heart rate), as well as a method to evaluate key principles influencing exercise- and thermoregulation in humans.

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.

Poor Diet, Stress, and Inactivity Converge to Form a "Perfect Storm" That Drives Alzheimer's Disease Pathogenesis

North American incidence of Alzheimer's disease (AD) is expected to more than double over the coming generation. Although genetic factors surrounding the production and clearance of amyloid-β and phosphorylated tau proteins are known to be responsible for a subset of early-onset AD cases, they do not explain the pathogenesis of the far more prevalent sporadic late-onset variant of the disease. It is thus likely that lifestyle and environmental factors contribute to neurodegenerative processes implicated in the pathogenesis of AD. Herein, we review evidence that (1) excess sucrose consumption induces AD-associated liver pathologies and brain insulin resistance, (2) chronic stress overdrives activity of locus coeruleus neurons, leading to loss of function (a common event in neurodegeneration), (3) high-sugar diets and stress promote the loss of neuroprotective sex hormones in men and women, and (4) Western dietary trends set the stage for a lithium-deficient state. We propose that these factors may intersect as part of a "perfect storm" to contribute to the widespread prevalence of neurodegeneration and AD. In addition, we put forth the argument that exercise and supplementation with trace lithium can counteract many of the deleterious consequences associated with excessive caloric intake and perpetual stress. We conclude that lifestyle and environmental factors likely contribute to AD pathogenesis and that simple lifestyle and dietary changes can help counteract their effects.

The effects of exercise referral schemes in the United Kingdom in those with cardiovascular, mental health, and musculoskeletal disorders: a preliminary systematic review

BACKGROUND

Exercise referral schemes within clinical populations may offer benefits for inactive and sedentary individuals, and improve and aid treatment of specific health disorders. This systematic review aims to provide an overview, and examine the impact, of exercise referral schemes in patients with cardiovascular, mental health, and musculoskeletal disorders. This review focuses on populations within the United Kingdom (UK) only, with an aim to inform national exercise referral policies and guidelines.

METHOD

Data was collected from specific sources using validated methodology through PRISMA. Systematic searches were performed using Locate, PubMed, Scopus and Pro Quest: Public Health databases. Thirteen studies met inclusion criteria set for each sub group. This included that all studies aimed to prevent, observe, or decrease ill-health relating to the disorder, participants over the age of sixteen, and health disorders and outcomes were reviewed. All studies were conducted in the UK only.

RESULTS

In the 13 articles, a variety of modes and types of exercise were utilised. One-to-one supervised exercise sessions based in a gym environment were most frequently employed. Results showed that longer length schemes (20+ weeks) produced better health outcomes, and had higher adherence to physical activity prescribed, than those of shorter length (8-12 weeks). In patients referred with cardiovascular disorders, cardiovascular-related measures showed significant decreases including blood pressure. Schemes increased physical activity levels over the length of scheme for all disorders.

CONCLUSION

Longer length schemes (20+ weeks) improved adherence to physical activity prescribed over the course of the scheme, and could support longer term exercise adherence upon completion, however additional research on larger samples should examine this further. An implication is that schemes currently recommended in guidelines do not tailor programmes to support long term adherence to exercise, which must be addressed. There is currently a lack of research examining programmes tailored to suit the individual's health conditions thus further research might allow providers to tailor delivery and build upon policy recommendations in the UK.

Endurance- and Resistance-Trained Men Exhibit Lower Cardiovascular Responses to Psychosocial Stress Than Untrained Men

Evidence shows that regular physical exercise reduces physiological reactivity to psychosocial stress. However, previous research mainly focused on the effect of endurance exercise, with only a few studies looking at the effect of resistance exercise. The current study tested whether individuals who regularly participate in either endurance or resistance training differ from untrained individuals in adrenal and cardiovascular reactivity to psychosocial stress. Twelve endurance-trained men, 10 resistance-trained men, and 12 healthy but untrained men were exposed to a standardized psychosocial stressor, the Trier Social Stress Test. Measurements of heart rate, free salivary cortisol levels, and mood were obtained throughout the test and compared among the three groups. Overall, both endurance- and resistance-trained men had lower heart rate levels than untrained men, indicating higher cardiac performance of the trained groups. Trained men also exhibited lower heart rate responses to psychosocial stress compared with untrained men. There were no significant group differences in either cortisol responses or mood responses to the stressor. The heart rate results are consistent with previous studies indicating reduced cardiovascular reactivity to psychosocial stress in trained individuals. These findings suggest that long-term endurance and resistance trainings may be related to the same cardiovascular benefits, without exhibiting strong effects on the cortisol reactivity to stress.

High-intensity handgrip training lowers blood pressure and increases heart rate complexity among postmenopausal women: a pilot study

OBJECTIVE

Handgrip exercise is an emerging strategy for resting blood pressure (BP) reduction requiring minimal time and exercise effort. However, the research literature is currently limited to handgrip protocol designs predominantly prescribing sustained grip contractions, with little assessment of alternative options. Furthermore, our understanding of the utility of handgrip exercise would be strengthened by an evaluation of the physiological mechanisms driving BP reductions and an assessment of the interindividual response variability. As such, this research was designed to perform an initial evaluation of the pragmatic effectiveness of a novel at-home, high-intensity, unilateral (nondominant) handgrip exercise training program in reducing resting BP, while simultaneously exploring mediators of BP change including a neurocardiac index of autonomic nervous control [heart rate (HR) variability], measures of arterial stiffness (radial augmentation index and carotid-radial pulse wave velocity), and cardiovascular reactivity to psychophysiological stressors.

METHODS

Postmenopausal women were recruited to complete 8 weeks of handgrip exercise training. Aforementioned measures of resting BP and mediators of BP change were acquired at the midway point and end of training.

RESULTS

All participants (n=17) completed training with high self-reported adherence (96.9%) and improvement in grip strength (2.7±2.4kg, P<0.05). Handgrip training reduced resting systolic BP (-5.1±7.7 mmHg, P<0.05) and improved HR complexity (sample entropy: 0.24±0.31, P<0.05), without significant changes to resting diastolic BP, HR, or arterial stiffness (all P>0.05).

CONCLUSION

This pilot study successfully shows the potential utility of high-intensity intermittent handgrip exercise for improvements in cardiovascular health among postmenopausal women, with additional research required to further explore the underlying physiological mechanisms driving such improvements.

Gender differences in the association between physical activity and cognitive function in individuals with bipolar disorder

INTRODUCTION

Bipolar disorder (BD) is accompanied by a high number of comorbidities and associated with an overall increased mortality. Especially obesity, systemic inflammatory processes and cognitive deficits are highly prevalent and increase with the course of illness. Physical activity (PA) is associated with beneficial effects on somatic comorbidities such as obesity or cardiovascular disease in individuals without psychiatric disorder. Furthermore, PA might increase neurocognitive performance and reduce systemic inflammation.

OBJECTIVE

The aim of the study was to investigate the association between PA and neurocognitive function in euthymic individuals suffering from BD.

METHODS AND PARTICIPANTS

120 individuals with BD, euthymic at test time, completed the self-reported International Physical Activity Questionnaire (IPAQ) assessing PA of the past seven days and were accordingly assigned to a specific activity category (low, moderate or vigorous). Furthermore, clinical parameters were gathered and cognitive tests analysing verbal-dependent intelligence, attention, executive functioning as well as memory were administered.

RESULTS

Female individuals in the vigorous PA group performed significantly higher in most of the cognitive domains compared to females with moderate or low PA. In males, we only found a significant difference in one test for attention between moderate/vigorous and the low activity group.

CONCLUSION

Differences between PA groups in cognitive performance in female individuals with BD were obvious in almost all cognitive domains. As cognitive deficits are strongly associated with a worse course of disease and outcome, PA might offer a concomitant therapy targeting not only somatic comorbidities such as obesity and cardiovascular disease, but also neurocognition.

The Impact of Multidisciplinary Rehabilitation on Depressive Symptoms in Hemodialysis Patients

Depressive symptom is the most frequent psychological problem reported among chronic kidney disease (CKD) patients being treated by hemodialysis. This article evaluates the effectiveness of multidisciplinary rehabilitation on depressive symptoms in hemodialysis patients and clarifies the role of nurses. This quasi-experimental study was done on 30 patients in the hemodialysis center (educational hospital) in 2013. Eight rehabilitation plans were conducted by nurses. Beck Depression Inventory (BDI) was used before and after intervention. Our data were analyzed using descriptive and inferential statistics. Result of this study shows that there was a significant difference between mean depressive symptom score before (36.4 ± 10.9) and after (10.5 ± 3.1) rehabilitation ( p < .001). It is recommended that rehabilitation program be implemented in all hemodialysis centers with the participation of specialists in different fields.

Exercise and Sports Medicine Issues in Underserved Populations

Primary care providers can make a strong argument for exercise promotion in underserved communities. The benefits are vitally important in adolescent physical, cognitive, and psychological development as well as in adult disease prevention and treatment. In counseling such patients, we should take into account a patient's readiness for change and the barriers to exercise.

Fitter Women Did Not Have Attenuated Hemodynamic Responses to Psychological Stress Compared with Age-Matched Women with Lower Levels of Fitness

According to the 'cross stressor adaptation hypothesis', regular exercise acts as a buffer against the detrimental effects of stress. Nevertheless, evidence that higher levels of cardiorespiratory fitness moderate hemodynamic responses to acute psychological stress is inconclusive, especially in women. Women aged 30-50 years (in the mid-follicular phase of the menstrual cycle) with higher (n = 17) and lower (n = 17) levels of fitness were subjected to a Trier Social Stress Test (TSST). Continuous, non-invasive measurements were made of beat-to-beat, systolic blood pressure (SBP), diastolic blood pressure (DBP), mean arterial pressure (MAP), heart rate (HR), stroke volume (SV), cardiac output (CO), left ventricular ejection time (LVET), maximum slope, pulse interval (PI) and total peripheral resistance (TPR). Maximal oxygen consumption was significantly (p<0.001) higher in the 'higher fit' women. Lower fit women had higher fasting glucose, resting heart rate, waist to hip ratios and elevated serum triglyceride and cholesterol/ HDL ratios compared with higher fit women (p<0.05 for all). While all measured parameters (for both groups)displayed significant (p<0.001) responses to the TSST, only HR, PI and LVET differed significantly between higher and lower fit women (p<0.001 for all) with the higher fit women having the larger response in each case. It was also found that higher fit women had significantly shorter time to recovery for maximum slope compared with the lower fit women. These findings provide little support for the notion that higher levels of cardiorespiratory fitness result in lower cardiovascular responsivity to psychological stress in women but may indicate that lower fit women have blunted responses to stress.

The Impact of Long-Term Physical Activity Interventions for Overweight/Obese Postmenopausal Women on Adiposity Indicators, Physical Capacity, and Mental Health Outcomes: A Systematic Review

Physical activity interventions have recently become a popular strategy to help postmenopausal women prevent and manage obesity. The current systematic review evaluates the efficacy of physical activity interventions among overweight and obese postmenopausal women and sheds light on the behavioral change techniques that were employed in order to direct future research. Method. Five electronic databases were searched to identify all prospective RCT studies that examine the impact of physical activity on adiposity indicators, physical capacity, and/or mental health outcomes among healthy, sedentary overweight, and obese postmenopausal women in North America. The behavior change technique taxonomy was used to identify the various strategies applied in the programs. Results. Five RCTs met the inclusion criteria. The findings showed that adiposity indicators and physical capacity outcomes significantly improved following long-term interventions; however, mental health outcomes showed nonsignificant changes. Furthermore, 17 behavior change techniques were identified with the taxonomy across all trials. The intrapersonal-level techniques were the most common. Conclusion. Physical activity interventions had a positive effect on adiposity measures and physical capacity. Future research should focus on testing the effectiveness of physical activity interventions on mental health and incorporate strategies at the individual and environmental level to maximize the health impact on the population.

Effects of a 12-week endurance training program on the physiological response to psychosocial stress in men: a randomized controlled trial

The present study experimentally tested the cross-stressor adaptation hypothesis by examining whether endurance exercise training leads to reductions in the physiological stress response to a psychosocial stressor. We randomly assigned 149 healthy men to a 12-week exercise training, relaxation training, or a wait list control group. Before and after intervention we assessed the groups' physical fitness (lactate testing) and compared their physiological stress responses to the Trier Social Stress Test for Groups in terms of salivary free cortisol, heart rate (HR) and heart rate variability (HRV); the final sample consisted of 96 subjects. As hypothesized, the exercise training significantly improved fitness and reduced stress reactivity in all three parameters; however, it only improved stress recovery in terms of HR. The relaxation program reduced only cortisol, but not HR or HRV reactivity; no changes emerged for the control group. The findings suggest that the cross-stressor adaptation hypothesis is valid for cardiovascular as well as endocrine stress reactivity.

Concepts of scientific integrative medicine applied to the physiology and pathophysiology of catecholamine systems

This review presents concepts of scientific integrative medicine and relates them to the physiology of catecholamine systems and to the pathophysiology of catecholamine-related disorders. The applications to catecholamine systems exemplify how scientific integrative medicine links systems biology with integrative physiology. Concepts of scientific integrative medicine include (i) negative feedback regulation, maintaining stability of the body's monitored variables; (ii) homeostats, which compare information about monitored variables with algorithms for responding; (iii) multiple effectors, enabling compensatory activation of alternative effectors and primitive specificity of stress response patterns; (iv) effector sharing, accounting for interactions among homeostats and phenomena such as hyperglycemia attending gastrointestinal bleeding and hyponatremia attending congestive heart failure; (v) stress, applying a definition as a state rather than as an environmental stimulus or stereotyped response; (vi) distress, using a noncircular definition that does not presume pathology; (vii) allostasis, corresponding to adaptive plasticity of feedback-regulated systems; and (viii) allostatic load, explaining chronic degenerative diseases in terms of effects of cumulative wear and tear. From computer models one can predict mathematically the effects of stress and allostatic load on the transition from wellness to symptomatic disease. The review describes acute and chronic clinical disorders involving catecholamine systems-especially Parkinson disease-and how these concepts relate to pathophysiology, early detection, and treatment and prevention strategies in the post-genome era.

Effect of Endurance Cardiovascular Training Intensity on Erectile Dysfunction Severity in Men With Ischemic Heart Disease

The protective effect of physical activity on arteries is not limited to coronary vessels, but extends to the whole arterial system, including arteries, in which endothelial dysfunction and atherosclerotic changes are one of the key factors affecting erectile dysfunction development. The objective of this study was to report whether the endurance training intensity and training-induced chronotropic response are linked with a change in erectile dysfunction intensity in men with ischemic heart disease. A total of 150 men treated for ischemic heart disease, who suffered from erectile dysfunction, were analyzed. The study group consisted of 115 patients who were subjected to a cardiac rehabilitation program. The control group consisted of 35 patients who were not subjected to any cardiac rehabilitation. An IIEF-5 (International Index of Erectile Function) questionnaire was used for determining erectile dysfunction before and after cardiac rehabilitation. Cardiac training intensity was objectified by parameters describing work of endurance training. The mean initial intensity of erectile dysfunction in the study group was 12.46 ± 6.01 (95% confidence interval [CI] = 11.35-13.57). Final erectile dysfunction intensity (EDI) assessed after the cardiac rehabilitation program in the study group was 14.35 ± 6.88 (95% CI = 13.08-15.62), and it was statistically significantly greater from initial EDI. Mean final training work was statistically significantly greater than mean initial training work. From among the parameters describing training work, none were related significantly to reduction of EDI. In conclusion, cardiac rehabilitation program-induced improvement in erection severity is not correlated with endurance training intensity. Chronotropic response during exercise may be used for initial assessment of change in cardiac rehabilitation program-induced erection severity.

Exercise capacity is associated with endothelin-1 release during emotional excitement in coronary artery disease patients

Endothelin-1 (ET-1), a potent vasoconstrictor, IL-6, and catecholamines are increased and heart rate variability [SD of normal to normal R-R intervals (SDNN)] decreased during emotional excitement, but individual responses vary. We tested the hypothesis that exercise capacity is associated with physiological responses caused by real-life emotional excitement. We measured the plasma levels of ET-1, IL-6, catecholamines, heart rate, and SDNN in enthusiastic male ice hockey spectators (n = 51; age, 59 ± 9 years) with stable coronary artery disease (CAD) at baseline and during the Finnish National Ice Hockey League's final play-off matches. Maximal exercise capacity (METs) by bicycle exercise test and left ventricular ejection fraction (LVEF) were measured on a separate day. ET-1 response from baseline to emotional excitement correlated with maximal METs (r = -0.30; P = 0.040). In a linear stepwise regression analysis age, body mass index (BMI), METs, LVEF, basal ET-1, and subjective experience of excitement were entered the model as independent variables to explain ET-1 response. This model explained 27% of ET-1 response (P = 0.003). Maximal METs were most strongly correlated with ET-1 response (β = -0.45; partial correlation r = -0.43; P = 0.002), followed by BMI (β = -0.31; partial correlation r = -0.31; P = 0.033) and LVEF (β = -0.30; partial correlation r = -0.33; P = 0.023). Exercise capacity may protect against further cardiovascular events in CAD patients, because it is associated with reduced ET-1 release during emotional excitement.

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.

Changes in cardiorespiratory fitness in cardiac rehabilitation patients: a meta-analysis

BACKGROUND/OBJECTIVES

Improving patients' cardiorespiratory fitness is an important therapeutic outcome in cardiac rehabilitation. The ability of cardiac rehabilitation to reduce mortality and morbidity has been evidenced through several meta-analyses. Whether cardiac rehabilitation can increase cardiorespiratory fitness and which factors may influence such gains are less well quantified.

METHODS

We performed detailed literature searches of electronic databases and manually searched papers concerning changes in cardiorespiratory fitness in cardiac rehabilitation patients. We performed random-effects meta-analysis of mean improvements in cardiorespiratory fitness and subgroup analyses to determine potential sources of heterogeneity.

RESULTS

Data from 31 studies produced 48 groups (n=3827) with a mean improvement of 1.55 (95% CI 1.21-1.89) METs, (p<0.001); equivalent to standardised effect size of ES=0.97 (95% CI 0.80-1.13). As this value was highly heterogeneous (Q=852, p<0.001) we performed subgroup analyses on the effect size data. Gains in fitness were highest in patients receiving >36 exercise sessions in studies where fitness was assessed using the Naughton Protocol. Patient characteristics associated with the highest fitness gains were age (being young) and sex (being male training in a male-only exercise group). Changes in fitness were unrelated to programme type (comprehensive or exercise-only), duration or study design. There was no association with patient's baseline fitness levels.

CONCLUSION

This is the first meta-analysis of changes in cardiovascular fitness in cardiac rehabilitation patients and shows clinically significant improvements in a large sample of patients from a variety of rehabilitation programmes. This analysis helps describe the characteristics of cardiac rehabilitation programmes which can increase patients' cardiorespiratory fitness.

Stimulant reduction intervention using dosed exercise (STRIDE) - CTN 0037: study protocol for a randomized controlled trial

Background

There is a need for novel approaches to the treatment of stimulant abuse and dependence. Clinical data examining the use of exercise as a treatment for the abuse of nicotine, alcohol, and other substances suggest that exercise may be a beneficial treatment for stimulant abuse, with direct effects on decreased use and craving. In addition, exercise has the potential to improve other health domains that may be adversely affected by stimulant use or its treatment, such as sleep disturbance, cognitive function, mood, weight gain, quality of life, and anhedonia, since it has been shown to improve many of these domains in a number of other clinical disorders. Furthermore, neurobiological evidence provides plausible mechanisms by which exercise could positively affect treatment outcomes. The current manuscript presents the rationale, design considerations, and study design of the National Institute on Drug Abuse (NIDA) Clinical Trials Network (CTN) CTN-0037 Stimulant Reduction Intervention using Dosed Exercise (STRIDE) study.

Methods/Design

STRIDE is a multisite randomized clinical trial that compares exercise to health education as potential treatments for stimulant abuse or dependence. This study will evaluate individuals diagnosed with stimulant abuse or dependence who are receiving treatment in a residential setting. Three hundred and thirty eligible and interested participants who provide informed consent will be randomized to one of two treatment arms: Vigorous Intensity High Dose Exercise Augmentation (DEI) or Health Education Intervention Augmentation (HEI). Both groups will receive TAU (i.e., usual care). The treatment arms are structured such that the quantity of visits is similar to allow for equivalent contact between groups. In both arms, participants will begin with supervised sessions 3 times per week during the 12-week acute phase of the study. Supervised sessions will be conducted as one-on-one (i.e., individual) sessions, although other participants may be exercising at the same time. Following the 12-week acute phase, participants will begin a 6-month continuation phase during which time they will attend one weekly supervised DEI or HEI session.

Clinical Trials Registry

ClinicalTrials.gov, NCT01141608

http://clinicaltrials.gov/ct2/show/NCT01141608?term=Stimulant+Reduction+Intervention+using+Dosed+Exercise&rank=1

Physical activity moderates effects of stressor-induced rumination on cortisol reactivity

OBJECTIVE

Physically active individuals have lower rates of morbidity and mortality, and recent evidence indicates that physical activity may be particularly beneficial to those experiencing chronic stress. The tendency to ruminate increases and prolongs physiological stress responses, including hypothalamic-pituitary-adrenal (HPA) axis responses as indexed by cortisol reactivity to stressful experiences. We examined the association between ruminating in response to a laboratory stressor task and HPA axis reactivity and recovery and examined whether a physically active life-style moderates the associations between rumination and cortisol output trajectories.

METHODS

Forty-six postmenopausal women underwent the Trier Social Stress Test, whereas salivary cortisol was repeatedly measured. Twenty-five minutes after the end of the stressor, participants reported level of rumination in response to the stress.

RESULTS

Findings indicate that physical activity moderated the initial rate (B = -0.10, standard error = 0.04, p < .05) and curvature (B = -0.03, standard error = 0.01, p = .06) of the relationship between rumination and log-transformed cortisol trajectory. Among sedentary participants, those who responded to the stressor with higher levels of rumination had a more rapid initial increase in cortisol level (0.26 versus 0.21, p < .001), a later peak in cortisol reactivity (56 versus 39 minutes), and a delayed recovery from stress (curvature: -0.07 versus -0.08, p < .001) compared with those with lower levels of rumination. In active participants, cortisol trajectories were equivalent, regardless of the level of rumination.

CONCLUSIONS

In sum, individuals who maintain a physically active life-style may be protected against the effects of rumination on HPA axis reactivity to and recovery from acute stress.

Effects of aerobic exercise training on sympathetic and renal responses to mental stress in humans

The effects of aerobic exercise training (ET) on muscle sympathetic nerve activity (MSNA) and renal vascular responses to mental stress (MS) have not been determined in humans. We hypothesized that aerobic ET would reduce MSNA and renal vasoconstriction during MS. MSNA, mean arterial pressure (MAP), heart rate, renal blood flow velocity (RBFV), and peak oxygen uptake (V(O2peak)) were recorded in 23 healthy adults. Fourteen subjects participated in 8 wk of aerobic ET, while nine subjects served as sedentary controls (Con). ET significantly increased V(O2peak) (Delta18 +/- 1%; P < 0.001) and decreased RBFV at rest (60 +/- 4 to 48 +/- 3 cm/s; P < 0.01), whereas Con did not alter V(O2peak) or RBFV. ET did not alter resting MSNA (11 +/- 1 to 9 +/- 1 bursts/min) or MAP (84 +/- 2 to 83 +/- 2 mmHg), and these findings were similar in the Con group. MS elicited similar increases in MSNA (approximately Delta2 bursts/min; P < 0.05), MAP (approximately Delta15 mmHg; P < 0.001), and heart rate (approximately Delta20 beats/min; P < 0.001) before and after ET, and the responses were not different between ET and Con. Likewise, MS elicited similar decreases in RBFV and renal vascular conductance before and after ET, and the responses were not different between ET and Con. Perceived stress levels during MS were similar before and after the 8-wk study in both ET and Con. In conclusion, ET does not alter MSNA and renal vascular responses to MS in healthy humans.

Reducing psychosocial stress: a novel mechanism of improving survival from exercise training

BACKGROUND

Exercise training reduces mortality in patients with coronary artery disease. Behavioral characteristics, including depression, hostility, and overall psychosocial stress, have been shown to be independent risk factors for recurrent myocardial infarction and death in these patients. Exercise training can reduce these high-risk behaviors, but it remains uncertain as to what extent the health benefits of exercise training can be attributed to improving these behaviors.

METHODS

We evaluated the impact of exercise training during cardiac rehabilitation on mortality in 53 patients with coronary artery disease with high levels of psychosocial stress and in 469 patients with coronary artery disease with low levels of psychosocial stress and compared them with 27 control patients with high psychosocial stress who did not undergo formal cardiac rehabilitation and exercise training.

RESULTS

Mortality was approximately 4-fold greater in patients with high psychosocial stress than in those with low psychosocial stress (22% vs 5%; P = .003). Exercise training decreased the prevalence of psychosocial stress from 10% to 4% (P<.0001) and similarly improved peak oxygen uptake in patients with high and low psychosocial stress. Mortality in patients who improved exercise capacity by>or=10% (high exercise change) was 60% lower than in patients who had<10% improvement in exercise capacity (low exercise change) (P=.009). Mortality was lower in patients with high psychosocial stress with high exercise change compared with patients with high psychosocial stress with low exercise change (0% vs 19%; P=.009). In contrast, there was no significant improvement in mortality in patients with high versus low exercise change with low psychosocial stress (4% vs 8%; P=.14).

CONCLUSION

Psychosocial stress is an independent risk factor for mortality in patients with coronary artery disease, and exercise training can effectively reduce its prevalence. Exercise training reduces mortality in patients with coronary artery disease, and this effect seems to be mediated in part because of the salutary effects of exercise on psychosocial stress.

A walking program's attenuation of cardiovascular reactivity in older adults with silent myocardial ischemia

Silent myocardial ischemia (SI) has been linked to increased risk of future coronary events. Enhanced systolic and diastolic blood pressure (SBP and DBP, respectively) and heart-rate (HR) reactions to stress (cardiovascular reactivity [CVR]) have been associated with greater severity of SI and are related prospectively to coronary-artery-disease endpoints. The authors examined the potential attenuating effects of 6 months of walking (aerobic exercise) versus control on CVR to three laboratory stressors in 25 older adults with exercise-induced SI. Maximal aerobic capacity was significantly improved by 12% for the exercise group and decreased by 8% for controls (p < .001). Groups had similar biomedical profiles pre- and postintervention. Walkers had significantly reduced DBP reactivity (pre, 12 +/- 2; post, 4 +/- 2 mm Hg) compared with controls (pre, 10 +/- 2; post, 11 +/- 2 mm Hg; p = .05), but no differences between groups were found for SBP or HR reactivity. These findings are the first to suggest that increased physical activity (via walking) can attenuate BP reactivity to emotional stressors in apparently healthy older adults with SI.

Impact of cardiac rehabilitation on depression and its associated mortality

PURPOSE

Depression following major cardiac events is associated with higher mortality, but little is known about whether this can be reduced through treatment including cardiac rehabilitation and exercise training. We evaluated the impact of cardiac rehabilitation on depression and its associated mortality in coronary patients.

PATIENTS AND METHODS

We evaluated 522 consecutive coronary patients (381 men, 141 women; aged 64+/-10 years) enrolled in cardiac rehabilitation from January 2000 to July 2005 and a control group of 179 patients not completing rehabilitation. Depressive symptoms were assessed by questionnaire at baseline and following rehabilitation, and mortality was evaluated after a mean follow-up of 1296+/-551 days.

RESULTS

Prevalence of depressive symptoms decreased 63% following rehabilitation, from 17% to 6% (P <.0001). Depressed patients following rehabilitation had an over 4-fold higher mortality than nondepressed patients (22% vs 5%, P=.0004). Depressed patients who completed rehabilitation had a 73% lower mortality (8% vs 30%; P=.0005) compared with control depressed subjects who did not complete rehabilitation. Reductions in depressive symptoms and its associated mortality were related to improvements in fitness; however, similar reductions were noted in those with either modest or marked increases in exercise capacity.

CONCLUSION

In patients following major coronary events, cardiac rehabilitation is associated with both reductions in depressive symptoms and the excess mortality associated with it. Moreover, only mild improvements in levels of fitness appear to be needed to produce these benefits on depressive symptoms and its associated mortality.

Dehydration does not influence cardiovascular reactivity to behavioural stress in young healthy humans

Enhanced hydration increases the human cardiovascular reactivity to mental stress. If reduced water intake has the opposite effect, this would suggest controlling for water deprivation when studying such responses. Blood pressure, heart rate and parasympathetically dominated beat-to-beat heart rate fluctuations were assessed during resting baseline and mental stress. Two challenging cognitive-motor tasks, a 5-Choice Reaction Time Task (CRTT) and a Paced Auditory Serial Addition Task (PASAT), served as mental stress tests. Eight female and eight male volunteers were examined twice, after 24 h of water deprivation and after normal water intake (counterbalanced order, 7-day interval). Water deprivation resulted in moderate dehydration with a mean 2.6% decrease of total body weight. Dehydration did neither affect baseline blood pressure, heart rate, nor blood pressure reactivity to mental stress. However, dehydration slightly (-1.2 bpm) diminished heart rate reactivity to the PASAT (P = 0.03) and increased beat-to-beat heart rate fluctuations in response to the CRTT (P = 0.05). Dehydration intensified CRTT- and PASAT-induced reductions of beat-to-beat heart rate fluctuations in females (gender x dehydration interactions: P = 0.04-0.05). Moderate dehydration induced by water restriction has no effect on blood pressure reactivity to mental stress. The effects on heart rate reactivity are small. However, stress-induced parasympathetic withdrawal may be fortified during dehydration in females, which suggests controlling for water intake when studying such responses.

The protective role of exercise on stress system dysregulation and comorbidities

The human body, when under threat, elicits a set of neuroendocrine responses, including an increased secretion of glucocorticoids (GCs) and catecholamines from the adrenal gland and the activation of the sympathetic nervous system. These hormonal secretions allow a "fight or flight" response by mobilizing endogenous substrate and inducing a state of insulin resistance in the liver and skeletal muscles. Although the stress response was essential in ancient times to survive physical aggression, this threat has disappeared in our industrialized societies. However, in today's environment, the same stress responses can be elicited by emotional stimuli or professional and social stress. Such psychological stress may be protracted and unrelated to an increased metabolic demand. Thus, the energy mobilized is not used but is stored in visceral fat depots by the combined action of hypercortisolism and hyperinsulinemia. In addition, chronic activation of the stress system causes suppression of the gonadal, growth hormone (GH), and thyroid axes. These metabolic disturbances, in concert, lead to the clinical expression of a number of comorbidities including central obesity, hypertension, dyslipidemia, and endothelial dysfunction, all components of the metabolic syndrome and cardiometabolic risk factors. Moreover, chronic stress has deleterious effects on the brain and, in particular, affects hippocampal structure and function leading to cognitive and mood disturbances. Importantly, this stress-induced clinical phenotype is likely to be exaggerated in the presence of physical inactivity, resulting in a "stress-induced/exercise deficient" phenotype. Assuming that the stress response is a neuroendocrine mechanism that occurs in anticipation of physical action, then physical activity should be the natural means to prevent the consequences of stress. Indeed, accumulating evidence documents the beneficial effects of regular exercise in preventing or ameliorating the metabolic and psychological comorbidities induced by chronic stress. These benefits are thought to derive from a central effect of exercise to reduce the sensitivity to stress and also peripheral actions influencing metabolic functions and, in particular, insulin sensitivity and the partitioning of fuels toward oxidation rather than storage. It is concluded that chronic psychosocial stress, in the presence of physical inactivity, is likely to contribute to the epidemic of cardiometabolic and emotional disease of our current society. The way to prevent and combat this burden is by regular exercise.

Cardiorespiratory fitness and laboratory stress: a meta-regression analysis

We performed a meta-regression analysis of 73 studies that examined whether cardiorespiratory fitness mitigates cardiovascular responses during and after acute laboratory stress in humans. The cumulative evidence indicates that fitness is related to slightly greater reactivity, but better recovery. However, effects varied according to several study features and were smallest in the better controlled studies. Fitness did not mitigate integrated stress responses such as heart rate and blood pressure, which were the focus of most of the studies we reviewed. Nonetheless, potentially important areas, particularly hemodynamic and vascular responses, have been understudied. Women, racial/ethnic groups, and cardiovascular patients were underrepresented. Randomized controlled trials, including naturalistic studies of real-life responses, are needed to clarify whether a change in fitness alters putative stress mechanisms linked with cardiovascular health.

Prevalence of hostility in young coronary artery disease patients and effects of cardiac rehabilitation and exercise training

OBJECTIVE

To determine the prevalence of hostility symptoms in young patients with coronary artery disease (CAD), the associated risk factor profile in these patients, and the effects of a formal phase 2 cardiac rehabilitation and exercise training program.

PATIENTS AND METHODS

Our study included consecutive CAD patients referred for cardiac rehabilitation from May 1999 through December 2000. At baseline and after rehabilitation, behavioral factors and quality of life were assessed by validated questionnaires, and standard CAD risk factors were measured, including exercise capacity. We specifically evaluated detailed data for young patients.

RESULTS

A total of 500 patients were included in the study. Hostility scores were 2.5 times higher (P<.001) in the 81 young patients (< 50 years; mean +/- SD age, 45 +/- 5 years) than in the 268 elderly patients (> or = 65 years; mean +/- SD age, 70 +/- 4 years), and the prevalence of hostility symptoms was 3.5 times higher in young patients (28% vs 8%; P<.001). Young patients with hostility symptoms also had more adverse CAD risk profiles, including higher total cholesterol levels, triglyceride levels, total cholesterol/high-density lipoprotein cholesterol ratios, fasting glucose levels, and glycosylated hemoglobin levels and lower quality-of-life scores compared with young patients with low hostility scores. After cardiac rehabilitation, young patients with hostility symptoms had marked improvements in CAD risk factors, behavioral characteristics (including hostility), and quality of life, and a nearly 50% (P=.005) reduction in the prevalence of hostility symptoms occurred.

CONCLUSIONS

Young CAD patients have a high prevalence of hostility symptoms and adverse CAD risk profiles. Reducing hostility symptoms and other parameters of psychological distress in young CAD patients should be emphasized, and the potential benefits of cardiac rehabilitation programs in the secondary prevention of CAD should be highlighted.

Aerobic exercise training and cardiovascular reactivity to psychological stress in sedentary young normotensive men and women

Forty-five (22 women) sedentary young (18-30 years old) nonsmoking normotensive volunteers engaged in either 6 weeks of aerobic training (AT), weight training (WT), or a no-treatment (NT) condition to determine whether AT lowers systolic (SBP) and diastolic (DBP) blood pressure, heart rate (HR), and rate-pressure product (RPP) during rest, psychological stress, and recovery periods. Estimated VO(2)max increased for the AT (32.1+/-1.1 to 38.4+/-1.0 ml.kg(-1).min(-1)). A smaller increase for the WT (30.5+/-1.1 to 33.8+/-1.0) was likely due to increased leg strength, and VO(2)max did not change for the NT (32.5+/-1.1 to 32.9+/-1.0). Heart rate and RPP levels were lower during psychological stress and recovery after training for AT relative to the WT and NT. Overall SBP was also lower in the AT relative to the NT but not the WT. In conclusion, aerobic training lowered cardiovascular activity levels during psychological stress and recovery in healthy young adults, implying a protective role against age-related increases in coronary heart disease for individuals who adopt aerobic exercise early in life and maintain the behavior across the life span.

5-HT1A responsivity in patients with panic disorder before and after treatment with aerobic exercise, clomipramine or placebo

Blunted neuroendocrine and physiological responses to the selective 5-HT(1A) receptor agonist, ipsapirone, have been observed in patients with panic disorder and/or agoraphobia (PDA). In order to examine whether this hyporesponsiveness to ipsapirone is modified by pharmacological or non-pharmacological therapeutic interventions, challenges with an oral dose of ipsapirone (0.3 mg/kg) and placebo were performed in patients with PDA before and after 10 weeks of treatment with clomipramine, aerobic exercise and placebo. Before treatment, administration of ipsapirone was followed by significant increases of cortisol, anxiety and other psychopathological symptoms in comparison to the placebo challenge. In addition, a significant decrease of body temperature was observed. After the 10-week treatment period, the psychological responses to ipsapirone were significantly reduced in the clomipramine and the exercise group. In contrast, there was a non-significant trend towards higher cortisol responses after clomipramine and exercise treatment. The hypothermic response to ipsapirone was significantly reduced by clomipramine treatment. In conclusion, our results demonstrate that effective treatment of panic disorder has divergent effects on the psychological, neuroendocrine and temperature responses to ipsapirone.

Cigarette smoking and coronary blood flow

Cigarette smoking is associated with an increased risk for vascular disease. The effects of smoking and nicotine on coronary and peripheral arterial function have been probed with various invasive and noninvasive techniques. The current review provides a brief summary of the available techniques for measuring coronary or peripheral arterial function and discusses the determinants of myocardial blood flow at rest and during stress. Finally, it summarizes research addressing the effects of smoking on coronary and peripheral arterial function. Acute and chronic smoking does not appear to alter substantially endothelium independent coronary vasodilatory capacity. In contrast, active and passive smoking alters coronary and peripheral arterial vasomotion in patients with and individuals without coronary artery disease (CAD). Therefore, the site of the damaging effects of smoking appears to be the coronary endothelium. The smoking history is correlated with the degree of vasomotor abnormalities. Further, the degree of smoking-induced endothelial dysfunction appears to increase with the severity of CAD. Finally, the coronary endothelial and peripheral arterial vasomotor dysfunction observed in active and passive healthy smokers appear to be to some degree reversible.

Biobehavioral approaches to the treatment of essential hypertension

Despite recent advances in the medical management of hypertension, chronically elevated blood pressure remains a major health problem in the United States, affecting almost 50 million Americans. It is widely recognized that lifestyle factors contribute to the development and maintenance of elevated blood pressure. This article critically reviews current approaches to the nonpharmacological treatment of high blood pressure and highlights outcome studies of exercise, weight loss and dietary modification, and stress management and relaxation therapies. Methodological issues in the assessment and treatment of hypertension are discussed, along with possible mechanisms by which lifestyle modification may reduce elevated blood pressure.

Effects of moderate-intensity exercise on physiological, behavioral, and emotional responses to family caregiving: a randomized controlled trial

BACKGROUND

The study objective was to determine the health and quality-of-life effects of moderate-intensity exercise among older women family caregivers.

METHODS

This 12-month randomized controlled trial involved a volunteer sample of 100 women aged 49 to 82 years who were sedentary, free of cardiovascular disease, and caring for a relative with dementia. Participants were randomized to 12 months of home-based, telephone-supervised, moderate-intensity exercise training or to an attention-control (nutrition education) program. Exercise consisted of four 30- to 40-minute endurance exercise sessions (brisk walking) prescribed per week at 60% to 75% of heart rate reserve based on peak treadmill exercise heart rate. Main outcomes were stress-induced cardiovascular reactivity levels, rated sleep quality, and reported psychological distress.

RESULTS

Compared with nutrition participants (NU), exercise participants (EX) showed significant improvements in the following: total energy expenditure (baseline and post-test means [SD] for EX = 1.4 [1.9] and 2.2 [2.2] kcal/kg/day; for NU = 1.2 [1.7] and 1.2 [1.6] kcal/kg/day; p <.02); stress-induced blood pressure reactivity (baseline and post-test systolic blood pressure reactivity values for EX = 21.6 [12.3] and 12.4 [11.2] mm Hg; for NU = 17.9 [10.2] and 17.7 [13.8] mm Hg; p <.024); and sleep quality (p <.05). NU showed significant improvements in percentages of total calories from fats and saturated fats relative to EX (p values <.01). Both groups reported improvements in psychological distress. Conclusions. Family caregivers can benefit from initiating a regular moderate-intensity exercise program in terms of reductions in stress-induced cardiovascular reactivity and improvements in rated sleep quality.

Plasma catecholamine and cardiovascular reactivity during an acute high ropes course event

The primary purpose of this study was to describe physiological responses to an acute high ropes course stress. The selected dependent variables were epinephrine (E), norepinephrine (NE), heart rate (HR), systolic/diastolic blood pressure (BPs and BPd) and self-reported anxiety. A secondary purpose was to explore possible relationships between the observed physiological responses and physical fitness. College-age males were recruited for preliminary V(O(2)) max testing to identify a high-fit and low-fit subject pool. Eleven were identified as eligible participants and gave informed consent. Six participants were in the high-fit category (V(O(2)) max>60 ml/kg) and five in the low-fit category (V(O(2)) max<42 ml/kg). The Power Pole, a common high ropes course event, was selected as the acute field-based challenge activity. During participation in the challenge, a series of five (T1-T5) 10-ml blood samples were taken (via intravenous catheter) to be analyzed for E and NE. Subjective anxiety, HR, BPs and BPd were also measured at T1-T5. When the data were analyzed in a 2 (fitness group) x 5 (time) factorial ANOVA, there was a significant main effect for time with each dependent variable. However, the only difference between fitness levels was found with HR. These results indicate that the Power Pole is an acute field-based stressor for individuals of both high and low fitness levels. Due to the lack of difference between fitness groups for all variables other than HR, we conclude that participating in the Power Pole event elicits more stress of a psychosocial nature than stress of physical exertion.

Effects of exercise and weight loss on blood pressure during daily life

PURPOSE

The objective of this study was to investigate the effects of exercise training and weight loss on blood pressure (BP) associated with physical activity and emotional stress during daily life.

METHODS

One hundred twelve participants with unmedicated high normal or stage 1 to stage 2 hypertension were randomized to one of three conditions: a combined exercise and behavioral weight management group (WM), an exercise-only group (EX), or a wait list control group (CON). BP was assessed in the clinic and during 15 h of daytime ambulatory BP monitoring at baseline and after 6 months of treatment.

RESULTS

Increased levels of physical activity and emotional distress measured during daily life were associated with increases in systolic blood pressure (SBP), diastolic blood pressure (DBP), heart rate (HR), and rate pressure product (RPP). After treatment, the WM group had significantly lower DBP, HR, and RPP responses during both high and low levels of physical activity and emotional distress compared with the CON group. The EX group had similar BP levels as the WM group, although the EX group had significantly lower BP than the CON group during low but not high levels of physical activity and emotional distress.

CONCLUSION

These findings indicate that exercise, especially when combined with weight loss, reduces BP levels at rest and in situations that typically elevate BP such as intense physical activity and emotional distress.

A multibehavioral intervention to decrease cardiovascular disease risk factors in older men

The purpose of this study was to compare the effectiveness of two mutibehavioral interventions: stress management (SM) (nutrition, exercise, and stress management) and education (ED) (nutrition, exercise, and education) on reduction of cardiovascular disease (CVD) risk factors in older men. A convenience sample (n = 33) of older men (66 +/- 5 years) with at least one CVD risk factor participated in this 6-month intervention. Mean receiving the SM intervention (n = 25) exercised at the facility twice weekly (at > or = 70% maximum heart rate for 40 minutes) and received 12 hours each of nutrition and stress management class instruction. Men receiving the ED intervention (n = 8) received the same exercise and nutrition protocols but received 12 hours of education without stress management. There were no significant differences in body habitus, metabolic response, exercise endurance, blood pressure, or heart rate between groups at baseline. The SM group had significant pre-post differences in weight, body mass index, intraabdominal fat, subcutaneous fat, total cholesterol, low-density lipoprotein, triglycerides, VO2, supine systolic and diastolic blood pressures. The ED group demonstrated significant pre-post differences only in supine diastolic blood pressure. There were significant change score differences between the groups in triglycerides, subcutaneous fat, VO2, and body mass index. Results suggest that a 6-month multibehavioral intervention with stress management is effective in decreasing CVD risk factors in older men.

Effects of physical exercise on anxiety, depression, and sensitivity to stress: a unifying theory

Until recently, claims for the psychological benefits of physical exercise have tended to precede supportive evidence. Acutely, emotional effects of exercise remain confusing, both positive and negative effects being reported. Results of cross-sectional and longitudinal studies are more consistent in indicating that aerobic exercise training has antidepressant and anxiolytic effects and protects against harmful consequences of stress. Details of each of these effects remain unclear. Antidepressant and anxiolytic effects have been demonstrated most clearly in subclinical disorder, and clinical applications remain to be exploited. Cross-sectional studies link exercise habits to protection from harmful effects of stress on physical and mental health, but causality is not clear. Nevertheless, the pattern of evidence suggests the theory that exercise training recruits a process which confers enduring resilience to stress. This view allows the effects of exercise to be understood in terms of existing psychobiological knowledge, and it can thereby provide the theoretical base that is needed to guide future research in this area. Clinically, exercise training continues to offer clinical psychologists a vehicle for nonspecific therapeutic social and psychological processes. It also offers a specific psychological treatment that may be particularly effective for patients for whom more conventional psychological interventions are less acceptable.

Effects of exercise and weight loss on mental stress-induced cardiovascular responses in individuals with high blood pressure

The purpose of this study was to determine the effects of exercise and weight loss on cardiovascular responses during mental stress in mildly to moderately overweight patients with elevated blood pressure. Ninety-nine men and women with high normal or unmedicated stage 1 to stage 2 hypertension (systolic blood pressure 130 to 179 mm Hg, diastolic blood pressure 85 to 109 mm Hg) underwent a battery of mental stress tests, including simulated public speaking, anger recall interview, mirror trace, and cold pressor, before and after a 6-month treatment program. Subjects were randomly assigned to 1 of 3 treatments: (1) aerobic exercise, (2) weight management combining aerobic exercise with a behavioral weight loss program, or (3) waiting list control group. After 6 months, compared with control subjects, participants in both active treatment groups had lower levels of systolic blood pressure, diastolic blood pressure, total peripheral resistance, and heart rate at rest and during mental stress. Compared with subjects in the control group, subjects in the exercise and weight management groups also had greater resting stroke volume and cardiac output. Diastolic blood pressure was lower for the weight management group than for the exercise-only group during all mental stress tasks. These results demonstrate that exercise, particularly when combined with a weight loss program, can lower both resting and stress-induced blood pressure levels and produce a favorable hemodynamic pattern resembling that targeted for antihypertensive therapy.

Vagal and cardiac reactivity to psychological stressors in trained and untrained men

PURPOSE

The aim of this study was to determine whether higher aerobic fitness is associated with enhanced vagal influences on the myocardium, resulting in moderation of chronotropic cardiac activity during psychological stress and recovery.

METHOD

Heart period (HP) and respiratory sinus arrhythmia (RSA) were obtained from 10 aerobically trained (AT) and 10 untrained (UT) college-aged men at rest and during three contiguous psychological challenges and 3 min of recovery. Ratings of perceived stress were obtained at the end of the rest period, at the midpoint of each stressor, and at 30 s into recovery. Time series methods were used to quantify RSA from the beat-to-beat HP series. Responsivity was assessed both in terms of absolute levels of activity and phasic changes in activity (task or recovery minus baseline).

RESULTS

Both groups reported similar levels of subjective stress throughout the experiment. The AT exhibited longer HP at rest and during psychological stress and recovery than did the UT. However, the groups did not differ on RSA at rest or during psychological stress and recovery, nor did they differ on phasic changes in RSA or HP during stress or recovery. Additionally, aerobic capacity was not correlated with absolute levels or phasic changes in RSA during psychological challenge for either group and, except in Min 2 for the UT, similar results were obtained for recovery.

CONCLUSIONS

The results supported the hypothesis that, among young men, higher aerobic fitness is associated with longer HP at rest and during psychological stress and recovery. However, the lower cardiac chronotropic activation observed among the AT relative to the UT was not paralleled by a group difference in the amplitude of RSA. These results suggest that the group difference in HP was not mediated directly by the vagal mechanisms manifested in the amplitude of RSA.