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

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.

Move the night way: how can physical activity facilitate adaptation to shift work?

Shift work, involving night work, leads to impaired sleep, cognition, health and wellbeing, and an increased risk of occupational incidents. Current countermeasures include circadian adaptation to phase shift circadian biomarkers. However, evidence of real-world circadian adaptation is found primarily in occupations where light exposure is readily controlled. Despite this, non-photic adaptation to shift work remains under researched. Other markers of shift work adaptation exist (e.g., improvements in cognition and wellbeing outcomes) but are relatively unexplored. Timeframes for shift work adaptation involve changes which occur over a block of shifts, or over a shift working career. We propose an additional shift work adaptation timeframe exists which encompasses acute within shift changes in markers of adaptation. We also propose that physical activity might be an accessible and cost-effective countermeasure that could influence multiple markers of adaptation across three timeframes (Within Shift, Within Block, Within Work-span). Finally, practical considerations for shift workers, shift work industries and future research are identified.

Left Ventricular Ejection Time Measured by Echocardiography Differentiates Neurobehavioral Resilience and Vulnerability to Sleep Loss and Stress

There are substantial individual differences (resilience and vulnerability) in performance resulting from sleep loss and psychosocial stress, but predictive potential biomarkers remain elusive. Similarly, marked changes in the cardiovascular system from sleep loss and stress include an increased risk for cardiovascular disease. It remains unknown whether key hemodynamic markers, including left ventricular ejection time (LVET), stroke volume (SV), heart rate (HR), cardiac index (CI), blood pressure (BP), and systemic vascular resistance index (SVRI), differ in resilient vs. vulnerable individuals and predict differential performance resilience with sleep loss and stress. We investigated for the first time whether the combination of total sleep deprivation (TSD) and psychological stress affected a comprehensive set of hemodynamic measures in healthy adults, and whether these measures differentiated neurobehavioral performance in resilient and vulnerable individuals. Thirty-two healthy adults (ages 27-53; 14 females) participated in a 5-day experiment in the Human Exploration Research Analog (HERA), a high-fidelity National Aeronautics and Space Administration (NASA) space analog isolation facility, consisting of two baseline nights, 39 h TSD, and two recovery nights. A modified Trier Social Stress Test induced psychological stress during TSD. Cardiovascular measure collection [SV, HR, CI, LVET, BP, and SVRI] and neurobehavioral performance testing (including a behavioral attention task and a rating of subjective sleepiness) occurred at six and 11 timepoints, respectively. Individuals with longer pre-study LVET (determined by a median split on pre-study LVET) tended to have poorer performance during TSD and stress. Resilient and vulnerable groups (determined by a median split on average TSD performance) showed significantly different profiles of SV, HR, CI, and LVET. Importantly, LVET at pre-study, but not other hemodynamic measures, reliably differentiated neurobehavioral performance during TSD and stress, and therefore may be a biomarker. Future studies should investigate whether the non-invasive marker, LVET, determines risk for adverse health outcomes.

Joint associations of regular exercise and healthy diet with psychobiological stress reactivity in a healthy male sample

Objectives: Engaging in physical activity and exercise have long been shown to have beneficial effects on (psychosocial) stress reactivity. Initial studies could reveal that these positive effects on stress reactivity also exist for a healthy diet. Aim of this study was to examine whether combining a healthy diet and regular exercise can provide additional benefits on psychobiological stress levels. Methods: Forty-two men self-identifying as non-exercisers or regular exercisers between 18 and 30 years were exposed to the Trier Social Stress Test for Groups. Salivary cortisol (sCort) and alpha-amylase (sAA) as biological stress markers, and self-reported momentary stress were repeatedly examined. Questionnaires on regular exercise and dietary intake were completed once. Results: Two-stage hierarchical multiple regressions predicting participants' stress reactivity, i.e. response and recovery, from diet quality, exercise as well as their interaction appeared inconsistent. sCort response was significantly predicted by regular exercise whereas greater sCort recovery was predicted by higher diet quality. In contrast, higher sAA reactivity was predicted by higher diet quality while participants eating less healthy and exercising more showed the most pronounced sAA recovery. None of the other outcome variables was predicted by the interaction. Subjective stress was unrelated to either health behavior. Conclusions: The present examination among an all-male sample emphasized the stress-buffering capabilities of regular exercise and provided initial evidence for a distinct link to healthy diet. Assumed synergistic benefits could, however, not be confirmed. Advances are needed to better understand how individuals profit the most from which behaviors as well as their interactive effects.

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 effects of exercise training on hypothalamic-pituitary-adrenal axis reactivity and autonomic response to acute stress-a randomized controlled study

BACKGROUND

Exercise training is suggested to have a stress-buffering effect on physiological reactions to acute stress. The so-called cross-stressor adaptation hypothesis is one of many theories behind the plausible effects, proposing that the attenuated physiological reaction seen in trained individuals in response to acute exercise is also seen when the individual is exposed to acute psychosocial stress. However, few randomized controlled trials (RCT) are available in this field. Therefore, the aim of the present trial was to study the effects of a 6-month aerobic exercise intervention on the physiological response to acute laboratory stress.

METHODS

A two-armed RCT including untrained but healthy individuals aged 20-50 years was conducted. Assessments included a peak oxygen uptake test and a psychosocial stress test (the Trier Social Stress Test). A total of 88 participants went through both baseline and follow-up measures (48 in the intervention group and 40 in the control group) with a similar proportion of women and men (20 women and 28 men in the intervention group and 18 women and 22 men in the control group). Outcome measures were adrenocorticotrophic hormone, cortisol, systolic and diastolic blood pressure, and heart rate responses to acute psychosocial stress.

RESULTS

Oxygen uptake and time-to-exhaustion increased significantly following the intervention, while a decrease was seen in the control group. The analyses showed attenuated responses to acute psychosocial stress for all variables in both groups at follow-up, with no differences between the groups. No correlation was seen between amount of exercise training and reactivity to the stress test. Despite the increased oxygen uptake in the intervention group, no differences were seen between the groups for any of the outcome variables at follow-up.

CONCLUSIONS

In this study, the cross-stressor adaptation hypothesis could not be confirmed. Both groups showed decreased reactions indicating a habituation to the stress test.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02051127 . Registered on 31 January 2014-retrospectively registered.

Cardiorespiratory fitness, sleep, and physiological responses to stress in women

Epidemiological studies suggest that cardiorespiratory fitness (CRfitness) is associated with reduced risk of depression and anxiety in women, however, the mechanisms by which CRfitness may be protective against the development of these disorders are less clear. Because sleep problems are associated with both a higher risk for mental illness and altered physiological responses to stress, this study investigated whether sleep quality might influence the relationship between CRfitness and physiological stress responses in women. Thirty healthy women (18-45 y) who were medication-free, with regular menstrual cycles completed: (1) enrolment visit [including the assessment of CRfitness via maximal oxygen consumption during exercise]; (2) one-week sleep monitoring period including subjective (daily sleep diaries) and objective (wrist actigraphy) sleep measures; and (3) psychosocial stressor protocol (the Trier Social Stress Test; TSST) for the collection of heart rate (HR), blood pressure (BP), and salivary cortisol stress responses. Higher CRfitness was associated with reduced wake after sleep onset (WASO) duration (r = -.38, p = 0.04), higher self-reported sleep quality (higher scores reflect poorer sleep quality; r = -.37, p = 0.05), and lower HR (r = -.43, p = 0.02) during the stressor. Higher sleep quality was associated with a lower HR during the stressor (r = .44, p = 0.01). Increased WASO duration and WASO number were associated with blunted cortisol output during the stressor (r = -.44, p = 0.02, and r = -.46, p = 0.02, respectively). Results suggest that, in women, CRfitness may be protective against the deleterious effects of stress via improved sleep quality.

Acute psychosocial stress and working memory performance: the potential of physical activity to modulate cognitive functions in children

Background

Research suggests that physical activity (PA) enhances cognitive performance and prevents stress-related impairments of higher order cognitive functions like working memory (WM) performance. The aim of the current study was to investigate the effect of PA on WM performance after acute stress exposure in preadolescent children.

Methods

Regular PA was assessed for seven consecutive days during a typical school week using accelerometers in a sample of 44 preadolescent children (14 girls, M_age = 11.29 years, SD_age = 0.67). Following this period, participants performed an automated operational span (OSPAN) task immediately after being exposed to the Trier Social Stress Test for Children (TSST-C).

Results

Children exhibited prototypical response slopes in salivary cortisol and salivary α-amylase as markers of the endocrine and autonomic stress response immediately after psychosocial stress induction. A subsequent two-way ANOVA comparing high- and low-stress responders revealed a significant interaction between group affiliation and PA level on WM performance for both stress markers. Interestingly, best WM performance was demonstrated in children showing both high PA levels and high cortisol (or low α-amylase, respectively) stress responses.

Conclusions

Though patterns differed for salivary cortisol and salivary α-amylase, overall findings suggest that PA buffers the negative effects of stress on cognitive performance in children.

Habitual and acute exercise effects on salivary biomarkers in response to psychosocial stress

OBJECTIVE

Previous research suggests beneficial effects of physical exercise on stress reactivity due to cross-stressor adaptions of physiological stress response systems. However, results remain inconclusive and it is unclear whether only regular engagement in exercise modulates these physiological adaptations or if acute bouts of exercise can elicit similar adaptations. Thus, the aim of the current study was to investigate and compare the effects of habitual and acute exercise on physiological stress responses.

METHODS

84 male participants between 18 and 30 years (half of them were screened to be habitually high active or low active) were randomized into one of two groups: either an acute exercise intervention group (n = 42 with 50% being habitually high active) which engaged in 30 min of moderate-to-high intensity ergometer bicycling, or a control (placebo exercise) group which engaged in 30 min of light stretching (n = 42 with 50% being habitually high active). Following the intervention period, participants took part in a well validated psychosocial stress paradigm. Saliva samples were taken repeatedly to derive alpha-amylase and cortisol as stress-specific parameters. A multilevel growth curve approach was applied to analyse changes in the stress parameters over time.

RESULTS

Both, acute and habitual exercise have shown to be positively related to stress reactivity. In particular, a reduction in stress activation was found for both types of exercise, but only habitual engagement in exercise exhibited a beneficial effect on peak cortisol levels.

CONCLUSIONS

Taken together, people can profit from regular exercise (i.e. reduced activity of stress-response systems). However, even acute bouts of exercise preceding stress exposure showed beneficial effects on stress reactivity. This finding is particularly important as it may provide a (self-)regulatory mechanism for people facing conceivable acute stress situations.

Influence of Regular Physical Activity and Fitness on Stress Reactivity as Measured with the Trier Social Stress Test Protocol: A Systematic Review

BACKGROUND

Psychosocial stress is associated with multiple health complaints. Research to date suggests that regular physical activity (PA) and higher cardiorespiratory fitness may reduce stress reactivity and therefore contribute to a reduction of stress-related risk factors. While previous reviews have not differentiated between stressors, we focus on psychosocial stress elicited with the Trier Social Stress Test (TSST).

OBJECTIVE

Our objective was to examine the effect of regular PA and cardiorespiratory fitness on stress reactivity, with a particular focus on the TSST. The TSST is the laboratory task most widely used to induce socio-evaluative stress and elicits stronger stress reactions than most other cognitive stressor tasks.

METHODS

A systematic search within various databases was performed in January 2018. The following outcomes were considered: cortisol, heart rate, psychological stress reactivity, and potential moderators (age, sex, exercise intensity, assessment mode, and psychological constructs).

RESULTS

In total, 14 eligible studies were identified. Cortisol and heart rate reactivity were attenuated by higher PA or better fitness in seven of twelve studies and four of nine studies, respectively. Two of four studies reported smaller increases in anxiety and smaller decreases in calmness in physically active/fitter participants. Three of four studies found that higher PA/fitness was associated with more favorable mood in response to the TSST.

CONCLUSION

About half of the studies suggested that higher PA/fitness levels were associated with an attenuated response to psychosocial stress. Currently, most evidence is based on cross-sectional analyses. Therefore, a great need for further studies with longitudinal or experimental designs exists.

Openness to experience and stress responsivity: An examination of cardiovascular and underlying hemodynamic trajectories within an acute stress exposure

The personality trait openness to experience has been implicated in health, and in particular cardiovascular wellbeing. In a sample of 62 healthy young female adults, the role of openness in cardiovascular responsivity during a stress exposure was examined. Traditionally, methodologies have averaged a stress exposure into a single reading. This may be limited in that it does not consider patterns of cardiovascular adaptation within a stress exposure. Continuous cardiovascular data were reduced to mean 10 second readings, with phases determined through examinations of shifts in responsivity between each 10 second pairing. Analyses revealed a significant linear interaction for openness across the entire exposure for systolic blood pressure, and cardiac output. A significant between-subjects effect for heart rate also emerged. Contrary to their lower counterparts, those highest in openness exhibited an increasingly myocardial hemodynamic response profile throughout the exposure. Comparisons of responsivity suggests adaptive stress response trajectories for those highest in openness. This study also provides evidence that an attenuation of myocardial responsivity may underpin blunted responsivity. This study provides a potential mechanism in reported openness-health associations.