The Impact of Aerobic Training on Cardiovascular Reactivity to and Recovery From Psychological and Orthostatic Challenge.

OBJECTIVE: Elevated cardiovascular reactivity to, and reduced recovery from, challenging events may increase the risk of cardiovascular disease, and exercise training may reduce this reactivity. However, in a randomized controlled trial of aerobic versus strength training in sedentary, healthy young adults, we found no training group differences in reactivity or recovery. Because strength training also may have a reactivity-reducing effect, we conducted a secondary analysis of data from another trial, this time with a wait-list control condition. METHODS: One hundred nineteen healthy, young, sedentary adults were randomized to a 12-week aerobic training program or wait-list control. Before (T1) and after (T2) training and after 4 weeks of sedentary deconditioning (T3), we measured heart rate (HR), heart rate variability, and blood pressure at rest and in response to and recovery from psychological and orthostatic challenge. Data were analyzed using a group (aerobic versus wait-list) by session (T1, T2, and deconditioning) and by period (baseline, psychological challenge, recovery, standing) three-way analysis of variance with prespecified contrasts. RESULTS: Aerobic capacity significantly increased at T2 and decreased at T3 only in the aerobic training group. The groups did not differ on HR, heart rate variability, or blood pressure reactivity to or recovery from challenge. Without baseline adjustment, there were no significant treatment differences in response to challenges. With baseline adjustment, there were significant treatment by session effects for HR (Cohen d = 0.54, p = .002), systolic blood pressure (d = 0.44, p = .014), diastolic blood pressure (d = 0.74, p = .002), and root mean squared successive difference (d = 0.48, p = .006) reactivity from T1 to T2 only for orthostatic challenge: at T2, reactivity in the aerobic group was nonsignificantly reduced, compared with T1. In the wait-list group, reactivity significantly increased after T1. CONCLUSIONS: This study raises further doubt about attenuation of cardiovascular reactivity or enhancement of recovery as a cardioprotective mechanism of aerobic exercise training.Clinical Trial Registration:ClinicalTrials.gov Unique identifier: NCT01335737.

The Association of Cigarette Smoking With High-Frequency Heart Rate Variability: An Ecological Momentary Assessment Study.

OBJECTIVE: Evidence from both laboratory and observational studies suggests that acute and chronic smoking leads to reduced high-frequency heart rate variability (HF-HRV), a measure of cardiac vagal regulation. We used ecological momentary assessment (EMA) to study the effect of smoking on concurrent HF-HRV in a trial measuring the effects of hostility reduction and compared 24-hour HF-HRV in smokers and nonsmokers. METHOD: Ambulatory electrocardiogram data were collected before randomization from 149 healthy individuals with high hostility levels (20-45 years, body mass index ≤ 32 kg/m) and paired with concurrent EMA ratings of smoking and physical position during waking hours. A multilevel mixed model was estimated associating ln(HF-HRV) from smoking status (between-person factor) and person-centered momentary smoking (within-person factor, treated as a random effect), adjusting for momentary physical position, medication use, and consumption of alcohol and caffeine. RESULTS: Thirty-five smokers and 114 nonsmokers provided both EMA and HF-HRV data. Within smokers, ln HF-HRV was reduced by 0.31 millisecond (p = .04) when participants reported having recently smoked cigarettes, compared with when they had not. The 24-hour HF-HRV was significantly lower in smokers (M [SD] = 5.24 [0.14] milliseconds) than nonsmokers (5.63 ± 0.07 milliseconds, p = .01). CONCLUSIONS: In healthy smokers with high hostility levels used as their own controls during daily living, smoking acutely reduced HF-HRV. HF-HRV was also reduced in smokers as compared with nonsmokers. Although limited by a small sample of individuals with high hostility levels, these findings nonetheless provide additional evidence that cardiac vagal regulation is lowered by cigarette smoking, which may be one of the numerous pathophysiological effects of smoking.

The Effect of Hostility Reduction on Autonomic Control of the Heart and Vasculature: A Randomized Controlled Trial.

OBJECTIVE: Hostility is associated with coronary artery disease. One candidate mechanism may be autonomic nervous system (ANS) dysregulation. In this study, we report the effect of cognitive behavioral treatment on ANS regulation. METHODS: Participants were 158 healthy young adults, high in hostility measured by the Cook-Medley Hostility and Spielberger Trait Anger scales. Participants were also interviewed using the Interpersonal Hostility Assessment Technique. They were randomized to a 12-week cognitive behavioral treatment program for reducing hostility or a wait-list control group. The outcome measures were preejection period, low-frequency blood pressure variability, and high-frequency heart rate variability measured at rest and in response to and recovery from cognitive and orthostatic challenge. Linear-mixed models were used to examine group by session and group by session by period interactions while controlling for sex and age. Contrasts of differential group and session effects were used to examine reactivity and recovery from challenge. RESULTS: After Bonferroni correction, two-way and three-way interactions failed to achieve significance for preejection period, low-frequency blood pressure variability, or high-frequency heart rate variability (p > .002), indicating that hostility reduction treatment failed to influence ANS indices. CONCLUSIONS: Reduction in anger and hostility failed to alter ANS activity at rest or in response to or recovery from challenge. These findings raise questions about whether autonomic dysregulation represents a pathophysiological link between hostility and heart disease.

Mortality predictors in a 60-year follow-up of adolescent males: exploring delinquency, socioeconomic status, IQ, high-school drop-out status, and personality.

OBJECTIVE: To examine whether socioeconomic status (SES), high school (HS) completion, IQ, and personality traits that predict delinquency in adolescence also could explain men's delinquency-related (Dq-r) mortality risk across the life span. METHODS: Through a 60-year Social Security Death Index (SSDI) follow-up of 1812 men from Hathaway's adolescent normative Minnesota Multiphasic Personality Inventory (MMPI) sample, we examined mortality risk at various ages and at various levels of prior delinquency severity. We examined SES (using family rent level), HS completion, IQ, and MMPI indicators simultaneously as mortality predictors and tested for SES (rent level) interactions with IQ and personality. RESULTS: We ascertained 418 decedents. Dq-r mortality peaked between ages 45 years to 64 years and continued through age 75 years, with high delinquency severity showing earlier and higher mortality risk. IQ and rent level failed to explain Dq-r mortality. HS completion robustly conferred mortality protection through ages 55 years and 75 years, explained IQ and rent level-related risk, but did not fully explain Dq-r risk. Dq-r MMPI scales, Psychopathic Deviate, and Social Introversion, respectively, predicted risk for and protection from mortality by age 75 years, explaining mortality risk otherwise attributable to delinquency. Wiggins' scales also explained Dq-r mortality risk, as Authority Conflict conferred risk for and Social Maladjustment and Hypomania conferred protection from mortality by age 75 years. CONCLUSIONS: HS completion robustly predicts mortality by ages 55 years and 75 years. Dq-r personality traits predict mortality by age 75 years, accounting, in part, for Dq-r mortality.

The effects of aerobic training on subclinical negative affect: A randomized controlled trial.

OBJECTIVE: The antidepressant and anxiolytic effects of aerobic exercise are well known, but less is known about its effects on subclinical levels of trait negative affect in healthy but sedentary adults. In the present study, we test the effects of a 3-month randomized controlled trial of aerobic exercise training in young to midlife adults on trait measures of depression, anxiety, hostility, and anger. METHOD: One-hundred and 19 men (n = 56) and women (n = 63) aged 20-45 were randomized to 1 of 2 conditions: (a) 12 weeks of aerobic exercise after which they were asked to halt exercising and decondition for 4 weeks, or (b) a 16-week waitlist control group. Assessments of depression, anxiety, hostility and anger were completed at study entry, Week 12 and Week 16. RESULTS: At study entry, participants scored low on measures of depression, anxiety, hostility and anger. Analyses among the intent-to-treat and per protocol samples found significant treatment effects of aerobic training for hostility and depression, but not for anxiety and anger. Within-group analyses demonstrated that depression and hostility scores decreased in the exercise group over the course of the intervention, while remaining stable in the control group. These effects persisted for the exercise group at nonsignificant levels after 4 weeks of deconditioning. CONCLUSIONS: Aerobic exercise training has significant psychological effects even in sedentary yet euthymic adults, adding experimental data on the known benefits of exercise in this population. (PsycINFO Database Record (c) 2020 APA, all rights reserved).

Effect of aerobic exercise on cognition in younger adults: A randomized clinical trial.

OBJECTIVE: To determine efficacy of aerobic exercise for cognitive function in younger healthy adults. METHODS: In a randomized, parallel-group, observer-masked, community-based clinical trial, 132 cognitively normal individuals aged 20-67 with below median aerobic capacity were randomly assigned to one of two 6-month, 4-times-weekly conditions: aerobic exercise and stretching/toning. Efficacy measures included aerobic capacity; cognitive function in several domains (executive function, episodic memory, processing speed, language, and attention), everyday function, body mass index (BMI), and cortical thickness. RESULTS: Aerobic capacity increased significantly (ß = 2.718; p = 0.003), and BMI decreased significantly (ß = -0.596; p = 0.013) in the aerobic exercise but not in the stretching/toning condition. Executive function improved significantly in the aerobic exercise condition; this effect was moderated by age (ß = 0.018 SD/y; p = 0.028). At age 40, the executive function measure increased by 0.228 SD (95% confidence interval [CI] 0.007-0.448), and by 0.596 SD (95% CI 0.219-0.973) at age 60. Cortical thickness increased significantly in the aerobic exercise group in a left frontal region and did not interact with age. Controlling for age and baseline performance, individuals with at least one APOE ε4 allele showed less improvement in executive function with aerobic exercise (ß = 0.5129, 95% CI 0.0381-0.988; p = 0.0346). CONCLUSIONS: This randomized clinical trial demonstrates the efficacy of aerobic exercise for cognition in adults age 20-67. The effect of aerobic exercise on executive function was more pronounced as age increased, suggesting that it may mitigate age-related declines. Increased cortical thickness suggests that aerobic exercise contributes to brain health in individuals as young as age 20. CLINICALTRIALSGOV IDENTIFIER: NCT01179958. CLASSIFICATION OF EVIDENCE: This study provides Class II evidence that for adults age 20-67 with below median aerobic capacity, aerobic exercise significantly improves executive function but not other measures of cognitive function.

Anger-reduction treatment reduces negative affect reactivity to daily stressors.

OBJECTIVE: Negative affect (NA) reactivity to daily stressors may confer health risks over and above stress exposure, especially in chronically angry adults. This randomized controlled trial tests the hypothesis that a 12-week cognitive-behavioral therapy (CBT) anger-reduction treatment would decrease NA reactivity to daily stressors assessed via ambulatory diary for those in treatment, but not on a wait-list for treatment. METHOD: Healthy adults (N = 158, aged 20-45 years, 53.20% women) scoring high on Spielberger's (1988) Trait Anger, a scale from the State-Trait Anger Expression Inventory, were randomly assigned to a CBT treatment or wait-list control group, and completed 24 hr of prerandomization and postintervention ecological momentary assessment (EMA) of NA intensity and stress events every 20 ± 5 min. A longitudinal model using a generalized estimating equation examined whether stressor exposure and NA reactions to momentary stressors changed from pre- to posttreatment in the CBT group. RESULTS: There was a significant 3-way interaction (t28 = 2.29, p = .03) between stressor, treatment group, and EMA day, indicating that NA reactivity decreased for the treatment group 1.60 points more than for the wait-list group (a 379.38% greater change in NA reactivity). NA during stressors was 1.18 points lower (a 28.42% decrease) for the treatment group at EMA Day 2 (p = .04), whereas wait-list NA during stressors nonsignificantly increased. CONCLUSION: CBT to decrease chronic anger is associated with lower NA reactivity to daily stressors in this sample and could be a promising treatment to mitigate the health impact of stress in this clinical population. (PsycINFO Database Record (c) 2019 APA, all rights reserved).

Activation of 5-HT1A autoreceptors in the dorsal raphe nucleus reduces the behavioral consequences of social defeat.

In animal models, serotonin (5-HT) activity contributes to stress-induced changes in behavior. Syrian hamsters (Mesocricetus auratus) exhibit a stress-induced change in behavior in which social defeat results in increased submissive and defensive behavior and a complete loss of normal territorial aggression directed toward a novel, non-aggressive opponent. We refer to this defeat-induced change in agonistic behavior as conditioned defeat. In this study we tested the hypothesis that 5-HT activity in the dorsal raphe nucleus (DRN) contributes to the acquisition and expression of conditioned defeat. We investigated whether injection of the selective 5-HT1A agonist flesinoxan (200 ng, 400 ng, or 800 ng in 200 nl saline) into the DRN would reduce the acquisition and expression of conditioned defeat. Additionally, we investigated whether injection of the selective 5-HT1A antagonist WAY 100635 (400 ng in 200 nl saline) into the DRN would enhance the acquisition and expression of conditioned defeat following a sub-optimal social defeat experience. We found that injection of flesinoxan into the DRN before exposure to a 15-min social defeat reduced the amount of submissive and defensive behavior shown at testing. We also found that injection of flesinoxan into the DRN before testing similarly reduced submissive and defensive behavior. In addition, we found that WAY 100635 enhanced conditioned defeat when injected either before social defeat or before testing. These data support the hypothesis that the activity of 5-HT cells in the DRN, as regulated by 5-HT1A autoreceptors, contributes to the formation and display of conditioned defeat. Further, our results suggest that 5-HT release in DRN projection regions augments defeat-induced changes in social behavior.