Does a 20-week aerobic exercise training programme increase our capabilities to buffer real-life stressors? A randomized, controlled trial using ambulatory assessment

Stress buffering effects of physical activity in adolescents: the moderating role of physical activity attitudes

BACKGROUND

Adolescents may experience stressful life events and associated physical and psychological symptoms of stress. Physical activity has a buffering effect on stress. However, whether physical activity attitudes modulate stress, and the relationship between physical activity attitudes, physical activity, and stress symptoms is unclear. The present study focuses on whether adolescent stress events predict stress symptoms, whether physical activity buffers stress, and whether this stress-buffering effect is enhanced when attitudes toward physical activity are positive.

METHODS

A stratified and cluster sampling method was used to select 2420 junior high school students from nine provinces from each of the three economic zones (with high GDP level, medium GDP level, and low GPD level) of eastern, western, and central China and the Adolescent Self-Rating Life Events Checklist, the Calgary Symptoms of Stress Inventory, the Physical Activity Rating Scale, and the behavioral attitude dimension of the Physical Activity Attitude Scale were used to investigate adolescent stress events, stress symptoms, physical activity, and physical activity attitudes respectively. There are 1,190 boys and 1,230 girls from seventh to ninth grade 12-15 years old.

RESULTS

Adolescents' stress events and stress symptoms showed a significant positive correlation (r = 0.479, P < 0.01). The more stressful events adolescents have, the more pronounced stress symptoms become. The interaction term between the total amount of physical activity and stress events was not influential on stress symptoms (P = 0.461), and neither was the distinction between high and moderate physical activity levels (Ph = 0.248, Pm = 0.245). There was a moderating effect of physical activity attitudes on stress buffering for moderate physical activity levels (P < 0.01). The moderating effect was stronger when adolescents had positive attitudes toward physical activity.

CONCLUSIONS

Adolescent physical activity can buffer the effects of stress events on stress symptoms when physical activity attitudes are positive, revealing that stimulating adolescents' physical activity initiative can promote physical activity to buffer stress.

Evaluation of low vagally-mediated heart rate variability as an early marker of depression risk

BACKGROUND

Both low vagally-mediated heart rate variability (HRV) and depression have been shown to be risk factors for cardiovascular disease (CVD). We recently identified an HRV cutpoint below which persons have an increased risk for several cardiometabolic disorders. However, no cutpoint exists to identify those at risk for depression.

METHODS

The association between daytime HRV and diagnostically validated depression cutoffs using the five-item World Health Organization Well-being Index (WHO-5) was examined in adults from the Mannheim Industrial Cohort Study (n = 9973; Mage = 41.9[10.9]; 20 % women [n = 1934]). The aim was to identify HRV cutpoints for individuals who may have clinical depression.

RESULTS

Regression adjusting for age, sex, and linear trend showed a significant quadratic association between depression, indexed by WHO-5 scores and HRV, indexed by the root mean square successive differences (RMSSD) in milliseconds (ms) (p < 0.001). Logistic regression models adjusting for age, sex, and heart period (i.e., inter-beat intervals) compared the clinically depressed (WHO-5 ≤ 28) and those with a screening diagnosis of depression (WHO-5 ≤ 50) to the rest of the population. Significant odds ratios suggested two RMSSD values 25 ± 2 ms (OR = 1.39 [1.17, 1.64]) and 35 ± 2 ms (OR = 1.17 [1.02, 1.34]) that may be used to identify those with an elevated risk for depression.

LIMITATIONS

The sample was primarily German men. Fitness and anti-depressant use were not available.

CONCLUSIONS

As HRV is a brief measure that can be used in clinical settings, our HRV cutpoints have implications for the early detection of those at risk for psychological and cardiometabolic disorders.

Association between different types of physical activity and occupational stress in Japanese workers: a cross-sectional study

This cross-sectional study investigated the association between different types of physical activity (PA) and occupational psychological and physical stress responses among workers in Japan. Stress responses were assessed using the Brief Job Stress Questionnaire. Work-related PA (time spent sitting, sitting bouts, standing, walking, engaging in heavy labor, and moderate-to-vigorous PA [MVPA]) and exercise-based PA (frequencies [times/week] of flexibility and muscle-strengthening activity, and walking) were measured using a questionnaire. Multiple linear regression was performed to examine the association between each type of PA and stress responses. Participants who engaged in >108 min/day of work-related MVPA exhibited a statistically significant association with higher psychological stress responses when compared to those who engaged in 0-42 min/day of work-related MVPA. For exercise-based PA, participants who engaged in flexibility activity or walking five or more times/week, or muscle-strengthening activity one to three times/week, demonstrated significantly lower psychological stress responses compared to those who did not exercise. Participants who engaged in flexibility activity five or more times/week demonstrated significantly lower physical stress responses compared to those who did not exercise. This study suggests that work-related MVPA is associated with higher psychological stress responses, while exercise-based PA is associated with lower psychological or physical stress responses.

The Effect of Physical Activity on Sleep Quality Among Chinese College Students: The Chain Mediating Role of Stress and Smartphone Addiction During the COVID-19 Pandemic

Purpose

During the period of COVID-19 pandemic, the social restrictions and isolation exerted a significant impact on the sleep quality of Chinese college students. This study aims to delve into the influence of physical activity on the sleep quality of college students as well as the mediating roles of stress and smartphone addiction.

Materials and Methods

A cohort of 274 eligible college students (146 males and 128 females) were selected for the investigation. The International Physical Activity Questionnaire Short Form, Stress Perception Scale, Smartphone Addiction Scale, and Pittsburgh Sleep Quality Index were employed to assess the levels of physical activity, stress, smartphone addiction, and sleep quality among college students. For data analysis, descriptive statistics, correlation analysis, and chained mediation effect tests were performed sequentially.

Results

The findings revealed: (1) a significant negative correlation between physical activity and stress, smartphone addiction, and sleep quality among college students (r = -0.216, p < 0.001; r = -0.224, p < 0.001; r = -0.259, p < 0.001); (2) independent mediating roles of stress and smartphone addiction in the relationship between physical activity and sleep quality; and (3) chained mediating effects of stress and smartphone addiction in the association between physical activity and sleep quality.

Conclusion

This study deepens our comprehension of how physical activity augments the quality of slumber, concurrently emphasizing that mitigating stress levels and alleviating smartphone addiction constitute effective strategies for preventing sleep issues among college students.

Combined associations of regular exercise and work-related moderate-to-vigorous physical activity with occupational stress responses: a cross-sectional study

Objective

The association between work-related moderate-to-vigorous physical activity (MVPA) and higher levels of stress response is recognized, but whether this association is moderated by regular exercise remains unclear. This cross-sectional study investigated whether exercise-based physical activity (PA) associates with lower levels of stress responses moderated by work-related MVPA.

Methods

The study participants comprised 863 workers from 35 small and medium-sized enterprises in Shimane prefecture, Japan, collected through convenient sampling from April 2021 to August 2022. The Brief Job Stress Questionnaire was used to assess stress responses. Work-related MVPA and exercise-based PA were measured using questionnaires. Multiple linear regression was used to analyze the combined variables of work-related MVPA and exercise-based PA. The reference group had no weekly exercise-based PA and >60 min of work-related MVPA.

Results

When work-related MVPA exceeded 60 min/day, flexibility activity or walking for ≥5 days/week (B = -3.53, 95% CI = -5.96, -1.11; B = -2.53, 95% CI = -4.90, -0.16) and muscle-strengthening activity 1-3 times/week (B = -3.52, 95% CI = -6.91, -0.12) were significantly associated with lower psychological stress response. Flexibility activity (B = -1.74, 95% CI = -3.01, -0.46) showed a similar link with physical stress response. When work-related MVPA was below 60 min/day, flexibility activity (B = -3.23, 95% CI = -6.01, -0.44; B = -3.29, 95% CI = -5.94, -0.63) or walking (B = -4.03, 95% CI = -6.62, -1.45; B = -3.10, 95% CI = -5.76, -0.44) practice 1-4 times/week and ≥5 times/week was significantly associated with lower psychological stress response.

Conclusion

Exercise-based PA greatly and consistently associates with a lower level of stress responses moderated by work-related MVPA.

The effectiveness of physical activity interventions in improving higher education students' mental health: A systematic review

Traditional interventions aiming to improve students' mental health and quality of life include meditation or canine therapy. The development of physical activity-related interventions has increased over the past decade. We aimed to review all studies using physical activity for improving the mental health and quality of life in higher education students whilst describing the interventions, measurements and effectiveness. A systematic search of six electronic databases including: ProQuest, MEDLINE, Embase, CINAHL, SPORTDiscus and CENTRAL, was conducted following PRISMA guidelines. Randomized or non-randomized controlled trial physical activity-related interventions involving higher education students aiming to improve their mental health and quality of life were included. Searches yielded 58 articles with interventions involving martial arts, sport, mind-body exercises and anaerobic exercises. Psychological measures varied across studies including the State Trait Anxiety Inventory, Beck Depression Inventory and the Perceived Stress Scale. Over half of the studies included in this review (n = 36) were effective in improving students' mental health or quality of life. Findings from our review suggest that interventions aiming to be effective in improving students' mental health quality of life should aim to deliver moderate-vigorous intensity exercises such as dance or Pilates. This systematic review was based on a published protocol in PROSPERO (registration number: CRD42022325975).

Affective reactions to real-life stressors and the role of physical activity in sports students - An Ambulatory Assessment study

Students are exposed to a variety of stressors that can negatively affect their health and performance. Using an Ambulatory Assessment approach, this study investigated whether and how positive affect (PA) and negative affect (NA) changed in response to real-life stressors in sports students. In addition, the study investigated how physical activity (PhyA) moderated affective reactions to stressors. 62 participants of a German university (m = 23, f = 38, d = 1; age: M = 21.55 years, SD = 2.47) reported their daily stressors, affective states and PhyA (context, intensity and duration) six times per day via smartphone over five days (30 prompts per participants). To test the hypotheses multilevel models were calculated. Stressor context predicted affective reactions. PA was lower and NA was higher when general (financial problems) or academic (exam periods) stressors were reported. General PhyA had a positive effect on sports students affect (higher PA, lower NA). However, when PhyA was performed in exercise classes within their study program and a stressor was reported, PA decreased. The results showed that certain stressors interact negatively with affective states. Furthermore, the results suggested that PhyA, depending on the context where it occurred, may also induce negative affective changes in this target group of sport students. More studies need to examine how PhyA moderates affective reactions to stressors and examine the influences of context specific PhyA (e.g., type of PhyA) in more detail.

Mechanism and implications of pro-nature physical activity in antagonizing psychological stress: the key role of microbial-gut-brain axis

Appropriate physical activities and a biodiversity-rich environment are conducive to the relief of psychological stress, and pro-nature physical activities are a combination of the two, which has good application potential in antagonizing psychological stress, but the intervention mechanism is still unclear. The microbiota-gut-brain axis is cyclically associated with psychological stress, and psychological stress can affect the microbiota through the gut-brain pathway, and conversely, the microbiota can also affect the psychological stress-induced symptoms. It is suggested that the microbe-gut-brain axis may provide a new perspective and target for the treatment of psychological stress-related diseases. Pro-nature physical activity can improve the number of Firmicutes, short-chain fatty acids, Akkermansia bacteria, and the gut-brain barrier and further affect the HPA axis, BDNF, and serotonin pathways of gut-brain two-way communication, thereby maintaining the body's homeostasis and reducing antagonistic psychological stress. According to the comprehensive influence of physical activities on the microbiota-gut-brain axis, a "green + exercise prescription hypothesis" in line with the holistic medical concept is revealed, which is expected to be effective in the prevention, alleviation, and treatment of irritable bowel syndrome and neurodegenerative diseases. It provides new means for treating psychological stress-related diseases such as mental disorders and mood disorders. In addition, it enlightens the construction of green infrastructure that is conducive to the diversified contact of microorganisms in outdoor physical activities venues and induces healthy interaction between the human body and the microbial population in the natural ecology. However, the current research is still in its early stages, and the intervention effect and mechanism of pro-nature physical activities need further demonstration in the future.

Use of Electronic Ecological Momentary Assessment Methodologies in Physical Activity, Sedentary Behavior, and Sleep Research in Young Adults: Systematic Review

BACKGROUND

Recent technological advances allow for the repeated sampling of real-time data in natural settings using electronic ecological momentary assessment (eEMA). These advances are particularly meaningful for investigating physical activity, sedentary behavior, and sleep in young adults who are in a critical life stage for the development of healthy lifestyle behaviors.

OBJECTIVE

This study aims to describe the use of eEMA methodologies in physical activity, sedentary behavior, and sleep research in young adults.

METHODS

The PubMed, CINAHL, PsycINFO, Embase, and Web of Science electronic databases were searched through August 2022. Inclusion criteria were use of eEMA; sample of young adults aged 18 to 25 years; at least 1 measurement of physical activity, sedentary behavior, or sleep; English language; and a peer-reviewed report of original research. Study reports were excluded if they were abstracts, protocols, or reviews. The risk of bias assessment was conducted using the National Heart, Lung, and Blood Institute's Quality Assessment Tool for Observational Cohort and Cross-Sectional Studies. Screening, data extraction, and risk of bias assessments were conducted by independent authors, with discrepancies resolved by consensus. Descriptive statistics and narrative synthesis were used to identify overarching patterns within the following categories guided by the Checklist for Reporting Ecological Momentary Assessments Studies: study characteristics, outcomes and measures, eEMA procedures, and compliance.

RESULTS

The search resulted in 1221 citations with a final sample of 37 reports describing 35 unique studies. Most reports (28/37, 76%) were published in the last 5 years (2017-2022), used observational designs (35/37, 95%), consisted of samples of college students or apprentices (28/35, 80%), and were conducted in the United States (22/37, 60%). The sample sizes ranged from 14 to 1584 young adults. Physical activity was measured more frequently (28/37, 76%) than sleep (16/37, 43%) or sedentary behavior (4/37, 11%). Of the 37 studies, 11 (30%) reports included 2 movement behaviors and no reports included 3 movement behaviors. eEMA was frequently used to measure potential correlates of movement behaviors, such as emotional states or feelings (25/37, 68%), cognitive processes (7/37, 19%), and contextual factors (9/37, 24%). There was wide variability in the implementation and reporting of eEMA procedures, measures, missing data, analysis, and compliance.

CONCLUSIONS

The use of eEMA methodologies in physical activity, sedentary behavior, and sleep research in young adults has greatly increased in recent years; however, reports continue to lack standardized reporting of features unique to the eEMA methodology. Additional areas in need of future research include the use of eEMA with more diverse populations and the incorporation of all 3 movement behaviors within a 24-hour period. The findings are intended to assist investigators in the design, implementation, and reporting of physical activity, sedentary behavior, and sleep research using eEMA in young adults.

TRIAL REGISTRATION

PROSPERO CRD42021279156; https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021279156.

Investigating associations between physical activity, stress experience, and affective wellbeing during an examination period using experience sampling and accelerometry

Previous studies reported that physical activity could buffer the negative association of psychological stress with affective wellbeing. However, the studies that examined this relation in everyday life have assessed physical activity only by self-report but not with objective measures such as accelerometry. We therefore investigated the associations of both subjectively and objectively measured physical activity with stress experiences and affective wellbeing. A total of 90 university students participated in a 10-day experience sampling and diary study during their examination period and reported about stress experiences, physical activity, and affective states. Physical activity was additionally assessed using accelerometry in 50 of the participants. Subjectively assessed physical activity and objectively assessed light physical activity were associated with feeling less stressed in the evening. Also, light physical activity during the day was associated with a smaller increase/higher decrease in feeling stressed from morning to evening. The association of stress experience with negative affect was moderated by objective light physical activity. No interactive effects of stress intensity and physical activity on affective wellbeing were found. On stressful days, physical activity may buffer the negative association between stress and affective wellbeing. Particularly light physical activity as assessed with accelerometry seems to play an important role. It may be beneficial for students' affective wellbeing to increase or at least maintain physical activity during examination periods.

Physiological relationship between cardiorespiratory fitness and fitness for surgery: a narrative review

Epidemiological evidence has highlighted a strong relationship between cardiorespiratory fitness and surgical outcomes; specifically, fitter patients possess heightened resilience to withstand the surgical stress response. This narrative review draws on exercise and surgical physiology research to discuss and hypothesise the potential mechanisms by which higher fitness affords perioperative benefit. A higher fitness, as indicated by higher peak rate of oxygen consumption and ability to sustain metabolic homeostasis (i.e. higher anaerobic threshold) is beneficial postoperatively when metabolic demands are increased. However, the associated adaptations with higher fitness, and the related participation in regular exercise or physical activity, might also underpin the observed perioperative benefit through a process of hormesis, a protective adaptive response to the moderate and intermittent stress of exercise. Potential mediators discussed include greater antioxidant capacity, metabolic flexibility, glycaemic control, lean body mass, and improved mood.

The impact of adolescents' health motivation on the relationship among mental stress, physical exercise, and stress symptoms during COVID-19: A dual moderation model

Objective

Many Chinese teenagers are experiencing high mental stress levels due to epidemic-related restrictions and closures. Mental stress can induce numerous associated symptoms, and physical exercise is considered to buffer mental stress. However, it remains unclear whether health motivation regulates the relationships among mental stress, physical exercise, and stress symptoms. This study examined whether mental stress events during the epidemic can predict stress symptoms, whether physical exercise can buffer mental stress, and whether the mental stress buffer effect is enhanced when health motivation regarding physical exercise is high.

Methods

In total, 2,420 junior high school students (1,190 boys and 1,230 girls; 826 seventh-grade students, 913 eighth-grade students, and 681 ninth-grade students) from nine provinces nationwide were selected to investigate mental stress events, symptoms, health motivation, and physical exercise in adolescents. The hypothesis was tested with a multiple regression analysis.

Results

A positive relationship between adolescent mental stress events and stress symptoms was observed, and an interactive relationship was found among health motivation, physical exercise, and mental stress factors. Specifically, the mental stress-buffering effect of physical exercise was significant only when health motivation was high.

Conclusion

In the post-epidemic period, the influence of mental stress events on stress symptoms in adolescents was found to be buffered by physical exercise only in terms of high health motivation. This result highlighted the role of health motivation in the buffering effect of physical exercise on mental stress during an epidemic.

Chinese college students COVID-19 phobia and negative moods: Moderating effects of physical exercise behavior

OBJECTIVE

We investigated the effects of COVID-19 fear on negative moods among college students, and assessed the efficacy of physical exercise behavior as a moderator variable.

METHODS

This was a cross-sectional study. Students from three colleges and universities in Shangqiu City, Henan Province and Yangzhou City, Jiangsu Province were enrolled in this study, which was performed during the COVID-19 pandemic using an online questionnaire. A total of 3,133 college students completed the questionnaire. Measurement tools included the COVID-19 Phobia Scale (C19P-S), Depression-Anxiety-Stress Self-Rating Scale (DASS), and the Physical Activity Behavior Scale (PARS-3).

RESULTS

During the COVID-19 pandemic, the rates of depression, anxiety, and stressful negative moods among college students were 35.5, 65.5, and 10.95%, respectively; there was a positive correlation between COVID-19 fear and negative moods among college students (r = 0.479, p < 0.001), which was negatively correlated with physical exercise behavior (r = -0.4, p < 0.001); the regulating effects of physical exercise behavior were significant (ΔR2 = 0.04, p < 0.001).

CONCLUSION

The rate of negative moods among college students is high, and the fear for COVID-19 is one of the key factors that lead to negative moods. Physical exercise can modulate the impact of COVID-19 fear among college students on negative moods. Studies should elucidate on mental health issues among different populations during the COVID-19 pandemic.

Does Exercise Training Improve Cardiac-Parasympathetic Nervous System Activity in Sedentary People? A Systematic Review with Meta-Analysis

The aim of this study was to investigate the training-induced effect on cardiac parasympathetic nervous system (PNS) activity, assessed by resting heart rate variability (HRV) and post-exercise heart rate recovery (HRR), in sedentary healthy people. Electronic searches were carried out in PubMed, Embase, and Web of Science. Random-effects models of between-group standardised mean difference (SMD) were estimated. Heterogeneity analyses were performed by means of the chi-square test and I2 index. Subgroup analyses and meta-regressions were performed to investigate the influence of potential moderator variables on the training-induced effect. The results showed a small increase in RMSSD (SMD+ = 0.57 [95% confidence interval (CI) = 0.23, 0.91]) and high frequency (HF) (SMD+ = 0.21 [95% CI = 0.01, 0.42]) in favour of the intervention group. Heterogeneity tests reached statistical significance for RMSSD and HF (p ≤ 0.001), and the inconsistency was moderate (I2 = 68% and 60%, respectively). We found higher training-induced effects on HF in studies that performed a shorter intervention or lower number of exercise sessions (p ≤ 0.001). Data were insufficient to investigate the effect of exercise training on HRR. Exercise training increases cardiac PNS modulation in sedentary people, while its effect on PNS tone requires future study.

Can Physical Exercise Help Deal With the COVID-19 Stressors? Comparing Somatic and Psychological Responses

This research aims to explore whether physical exercise can buffer the impact of the COVID-19 stressors. Based on the cross-stressor adaptation hypothesis, we proposed a moderated mediation model relating the COVID-19 stressors to sleep disorder via somatic and worry complaints, depending on the amount of physical exercise. A sample of working adults in Beijing (N = 207) filled surveys in two waves during the COVID-19 pandemic. Structural regression analysis showed that physical exercise moderates the impact of the COVID-19 stressors on sleep disorder via somatic complaints (index = -0.11, 95% CI [-0.22, -0.01]), rather than psychological worry complaints (index = -0.01, 95% CI [-0.07, 0.04]). Specifically, the COVID-19 stressors increase somatic complaints for people with a low amount of physical exercise (b = 0.17, p = 0.01]), while the COVID-19 stressors are not significantly related to somatic complaints for people with a high amount of physical exercise (b = -0.06, p = 0.33). This research extends the cross-stressor adaptation hypothesis and provides evidence on an individual intervention of physical exercise to deal with the COVID-19 pandemic.

The effect of aerobic exercises of different intensities on anxiety, cigarette addiction, sleep quality, and quality of life in former smokers

BACKGROUND

There is a worldwide struggle to quit smoking and prevent relapsing. Aerobic exercises are frequently utilized to aid in smoking cessation and prevent relapse.

AIMS

This study aimed to investigate the effects of aerobic exercises of different intensity on the level of anxiety, smoking addiction, and quality of sleep and life in former smokers.

METHODS

The study included 60 people aged 18 to 45 who had quit smoking within the previous month. Individuals were randomly assigned to control (CON), mild-intensity aerobic activity (MIA), and moderate-intensity aerobic activity (MoIA) groups. The MIA group did submaximal aerobic exercises at 40% of maximum heart rate (MHR), while the MoIA group did them at 60% of MHR for 8 weeks/3 days. Participants' anxiety levels were assessed using the Beck Anxiety Scale (BAS), smoking addiction was assessed using the Fagerström Test for Nicotine Dependence and Substance Craving Scale (SCS), sleep quality was assessed using the Pittsburgh Sleep Quality Index, and quality of life was assessed using the SF-36 Short Form Scale (SF-36).

RESULTS

The SCS score of the MoIA group declined more than the MIA and CON groups, and the MIA group had a lower sleep disturbance score than other groups when the influence of exercise training was assessed over time (p < 0.05). Aerobic exercise had no influence on SF-36 or BAS scores (p > 0.05).

CONCLUSIONS

The benefits of mild and moderate aerobic exercise on quality of life and anxiety are similar. However, mild-intensity aerobic exercises may be suitable for sleep difficulties while moderate-intensity aerobic exercises may be preferred for reducing smoking addiction.

The association of stress and physical activity: Mind the ecological fallacy

Psychological stress and physical activity are interrelated, constituting a relevant association to human health, especially in children. However, the association’s nature remains elusive, i.e., why psychological stress predicts both decreased and increased physical activity. To test whether effects vary as a function of the level of analyses, we derived intensive longitudinal data via accelerometers and stress questionnaires from 74 children across 7 days as they went about their daily routines (n = 513 assessments). Multilevel modelling analyses revealed that between children, higher psychological stress predicted decreased physical activity (standardized beta coefficient = −0.14; p = 0.046). Concurrently, within those children, higher psychological stress predicted increased physical activity across days (standardized beta coefficient = 0.09; p = 0.015). Translated to practice, children who experienced more stress than others moved less, but children were more active on days when they experienced heightened stress. This suggests that the analyses level is crucial to the understanding of the association between psychological stress and physical activity and should be considered to receive unequivocal results. If replicated, e.g., including high-frequency sampling and experimental manipulation in everyday life for in-depth insights on underlying mechanisms and causality, our findings may be translated to individually tailored (digital) prevention and intervention strategies which target children’s distress-feelings despite impairing their heightened physical activity in stressful situations and identify tipping points of chronic stress phases. Therefore, we especially call for more intensive longitudinal data approaches to tackle thus far neglected within-subject issues in the field of physical activity, sport and exercise research.

Examination stress in academic students: a multimodal, real-time, real-life investigation of reported stress, social contact, blood pressure, and cortisol

ObjectiveAcademic examinations are a frequent and significant source of student stress, but multimodal, psychophysiological studies are still missing. Participants & methods: Psychological and physiological variables were assessed on 154 undergraduate students in daily life using e-diaries resp. blood pressure devices at the beginning of the semester, and again before an examination. Results: Multilevel analysis revealed lower calmness, more negative valence, higher task-related stress, higher demands, lower perceived control, lower frequency of social contact, and a higher desire to be alone during the examination period (all p values < .0001), as well as lower ambulatory systolic blood pressure (p = .004), heightened cortisol at awakening (p = .021), and a smaller increase in cortisol (p = .012). Conclusions: Our study revealed empirical evidence that examination periods are not only associated with indicators of dysphoria, stress, and social withdrawal but also by altered physiological processes, which might reflect anticipatory stress and withdrawal effects.

Regulating interpersonal stress: the link between heart-rate variability, physical exercise and social perspective taking under stress

Social interactions can be stressful, especially if they involve provocation or ambiguity. At the same time, such interactions necessitate social cognition. The question thus arises how stress affects social cognition and how personality attributes modulate this effect. The aim of the current study was to investigate the link between emotional reactivity, physical exercise, and social cognition under stress. As a measure of social cognition, we used spontaneous perspective taking, i.e., the degree to which participants represented the mental state of another agent. Studying young female participants, we investigated how physiological regulation, measured through resting heart-rate variability, is related to spontaneous social perspective taking under stress, and to predicted anger in an ambiguous social scenario. When controlling for resting heart rate, vagally mediated heart-rate variability was negatively correlated with the effect of stress on perspective taking, indicating that good physiological regulation supports social cognition under stress. Further, participants who reported to exercise at least once a week showed higher perspective taking under stress than less active participants. Finally, we found tentative evidence for participants who exercised regularly to show reduced predicted anger in response to an ambiguous provocation. Our findings suggest that good physiological regulation and regular physical exercise support social cognition under stress.

High-Frequency Heart Rate Variability and Emotion-Driven Impulse Control Difficulties During Adolescence: Examining Experienced and Expressed Negative Emotion as Moderators

Emotion-driven impulse control difficulties are associated with negative psychological outcomes. Extant research suggests that high frequency heart rate variability (HF-HRV) may be indicative of emotion-driven impulse control difficulties and potentially moderated by negative emotion. In the current study, 248 eleven- to 14-year-olds and their parent engaged in a negatively emotionally arousing conflict task at Time 1. Adolescents' HF-HRV and negative emotional expression and experience were assessed before, during, and/or after the task. Adolescents reported on their levels of emotion-driven impulse control difficulties at Time 1 and one year later. Results revealed that higher levels of HF-HRV reactivity (i.e., higher HF-HRV augmentation) predicted higher levels of emotion-driven impulse control difficulties one year later among adolescents who experienced higher negative emotion. These findings suggest that negative emotional context should be considered when examining HF-HRV reactivity as a risk factor for emotion-driven impulse control difficulties and associated outcomes.

Chronic stress experience, sleep, and physical activity: Relations with change in negative affect and acute stress response to a naturalistic stressor

OBJECTIVES

Prior research indicates that chronic stress increases allostatic load and alters individuals' affective response to stress. Recent studies have linked health-related behaviours including poor sleep and physical inactivity with elevated negative affect responses to stress. This study extends prior work to investigate chronic stress experience, sleep, and physical activity as predictors of negative affect and acute stress experience during acute, sustained naturalistic stress.

DESIGN

Students (N = 637) were assessed during an academic semester and end-of-term final exam period.

METHODS

Self-report ratings of chronic stress experience, negative affect, acute stress experience, sleep, physical activity, demographics, and health were obtained. Hierarchical multiple regression analyses examined the extent to which chronic stress experience, sleep duration and sleep quality, habitual physical activity, and their interactions, predicted changes in negative affect and acute stress experience during final exams. Health-related behaviours were also examined as mediators between chronic stress experience and changes in negative affect and acute stress experience.

RESULTS

Greater chronic stress experience and shorter exam period sleep duration, but not habitual sleep duration or physical activity, predicted greater increases in negative affect and acute stress experience. Poorer overall sleep quality was a significant predictor in these models and partially mediated the relation between chronic stress experience and negative affect and acute stress experience.

CONCLUSIONS

Findings highlight the importance of chronic stress experience and sleep in predicting individuals' affective health during naturalistic stress. Interventions that reduce chronic stress experience and improve sleep may help individuals' buffer against impairments to affective health during these episodes.

App-Tailoring Requirements to Increase Stress Management Competencies Within Families: Cross-sectional Survey Study

Background

Families experiencing high levels of psychological distress are considered a particularly vulnerable population for adverse effects on mental and physical health. Moreover, highly stressed individuals engage less in mental health promoting activities and show low stress management competencies. App-based stress interventions seem promising for the treatment and prevention of stress outcomes and might be a low-threshold solution.

Objective

The aim of this study was to identify the requirements for a tailored app to reduce stress in a cohort of highly stressed families that have low stress management skills.

Methods

Parents (n=1008; age: mean 47.7 years, SD 6.1; female: 599/1008, 59.7%) completed an extensive web-based survey and were subdivided into a target (stressed individuals with low stress competency) and nontarget group according to their reported stress level and stress management competencies. Group differences were analyzed using analysis of variance. In principal component analysis with Kaiser varimax rotation, personally defined stress management goals were grouped into components. Linear regression models were also calculated.

Results

A 3-factor solution cumulatively explained 56% of the variance in personally defined goals of interest for stress management with (1) active strategies (25.61% explained variance), (2) general competency (17.95% explained variance) and (3) passive strategies (12.45% explained variance). The groups differed in age (F_1,978=27.67, P<.001), health index (F_1,958=246.14, P<.001), personally defined general-competency goal (F_1,958=94.16 P<.001), as well as “information acquisition” (F_1,971=14.75, P<.001) and “need for stimulation” (F_1,981=54.49, P<.001) personality traits. A regression model showed that for the active strategies goals of interest, only app feature information or instructional videos had a significant effect (P=.02). The general competency factor showed none, and the passive strategies factor showed significant effects for 2 app features—suggestions for planning possible activities with the family (P=.01) and diaries for documentation and development of strategies (P=.03).

Conclusions

The results of this survey study highlight the need to develop an app to increase stress management competencies that takes into consideration perceived stress level, stress management skills, personality, and personally defined goals of the user. The content of the app should be tailored to previously detected personality traits, especially selective information acquisition and low need for stimulation. Furthermore, personally defined stress management goals seem to affect interest in some features.

Direct and Stress-Buffering Effects of COVID-19-Related Changes in Exercise Activity on the Well-Being of German Sport Students

Maintaining or initiating exercise activity in the COVID-19 pandemic may act as a buffer against the observed stress-related deterioration in well-being, with emotion regulation (ER) discussed as a possible moderator. Therefore, the present study investigated the interaction between stress, exercise activity (EA), and ER on mood. In an online survey, 366 German sports science students (56% women, Mage = 23.04, SD = 2.87) reported their stress levels (general and COVID-19-specific), mood (energy, valence, calmness), EA before and during the pandemic, and use of ER strategies in spring 2020. Pandemic-related change in EA was calculated as residual change. Due to gender differences in mental health and EA, the main and interaction effects were tested in twelve hierarchical regression analyses, separately for men and women. Overall, EA significantly decreased during the pandemic and was positively associated with energy in both men and women. ER was positively associated with women's energy, but negatively with all three mood dimensions in men. Only one three-way interaction appeared significant: in the case of high stress, low levels of EA and high use of ER were associated with the greatest deteriorations in energy in men. Our findings suggest that EA may buffer deteriorations in energy in men with high stress and difficulties in ER.

Gait Patterns and Mood in Everyday Life: A Comparison Between Depressed Patients and Non-depressed Controls

Background

Previous laboratory findings suggest deviant gait characteristics in depressed individuals (i.e., reduced walking speed and vertical up-and-down movements, larger lateral swaying movements, slumped posture). However, since most studies to date assessed gait in the laboratory, it is largely an open question whether this association also holds in more naturalistic, everyday life settings. Thus, within the current study we (1) aimed at replicating these results in an everyday life and (2) investigated whether gait characteristics could predict change in current mood.

Methods

We recruited a sample of patients (n = 35) suffering from major depressive disorder and a sample of age and gender matched non-depressed controls (n = 36). During a 2-day assessment we continuously recorded gait patterns, general movement intensity and repetitively assessed the participant’s current mood.

Results

We replicated previous laboratory results and found that patients as compared to non-depressed controls showed reduced walking speed and reduced vertical up-and-down movements, as well as a slumped posture during everyday life episodes of walking. Moreover, independent of clinical diagnoses, higher walking speed, and more vertical up-and-down movements significantly predicted more subsequent positive mood, while changes in mood did not predict subsequent changes in gait patterns.

Conclusion

In sum, our results support expectations that embodiment (i.e., the relationship between bodily expression of emotion and emotion processing itself) in depression is also observable in naturalistic settings, and that depression is bodily manifested in the way people walk. The data further suggest that motor displays affect mood in everyday life.

Nurses' physical activity exploratory study: Caring for you so you can care for others

BACKGROUND

Nurses report the greatest stress of all health care workers. Although physical activity (PA) is associated with health benefits among other populations, nurses have stressors that other occupations do not typically encounter. It is important for nurses to identify techniques for stress management since stressors negatively impact their health and patient care.

OBJECTIVE

We aimed to examine the relationship between PA levels and physical, mental, and occupational health among nurses.

METHODS

Nurses (N = 62) completed measures of anthropometrics, demographics, and domains of physical, mental, and occupational health. Pearson correlations determined the relationship between PA and measures health along with the relationship between PA and health among active versus inactive nurses.

RESULTS

Fatigue was significantly correlated with moderate-to-vigorous PA (r = -0.27, p < 0.05). Relationships were found between mental health and light and moderate intensity PA (r = 0.40, p < 0.001; r = 0.30, p < 0.05).

CONCLUSIONS

Stress is prevalent among nurses and negatively impacts a nurse's health along with patient care. Findings suggest health benefits associated with PA among nurses. PA interventions among nurses may be needed to fully see the effects of PA on physical, mental, and occupational health, and ultimately patient health and safety.

Stress and mindfulness in Parkinson's disease - a survey in 5000 patients

Many Parkinson’s disease (PD) patients notice that motor symptoms worsen during stress, and experience stress-related neuropsychiatric symptoms such as anxiety and depression. Here we investigated which personal and disease characteristics are associated with perceived stress in PD, which PD symptoms are sensitive to stress, and we assessed self-reported benefits of stress-reducing strategies such as mindfulness. We sent an online survey to the Fox Insight cohort (n = 28,385 PD patients, n = 11,413 healthy controls). The survey included specific questions about the influence of stress on PD symptoms, use of stress-reducing strategies, and several validated scales measuring perceived stress, anxiety, dispositional mindfulness, rumination, and self-compassion. We received completed surveys from 5000 PD patients and 1292 controls. Patients perceived more stress than controls. Among patients, stress was correlated with increased rumination (R = 0.65), lower quality of life (R = −0.56), lower self-compassion (R = −0.65), and lower dispositional mindfulness (R = −0.48). Furthermore, patients indicated that stress significantly worsened both motor symptoms – especially tremor – and non-motor symptoms. Physical exercise was most frequently used to reduce stress (83.1%). Mindfulness was practiced by 38.7% of PD respondents, who noticed improvement in both motor and non-motor symptoms. Among non-users, 43.4% were interested in gaining mindfulness skills. We conclude that PD patients experience greater levels of stress than controls, and that stress worsens both motor and non-motor symptoms. Mindfulness may improve PD symptom severity, with the strongest effects on anxiety and depressed mood. These findings justify further controlled studies to establish the merits of mindfulness and other stress-alleviating interventions.

Relationships between incidental physical activity, exercise, and sports with subsequent mood in adolescents

Physical activity is beneficial for human physical health and well-being. Accordingly, the association between physical activity and mood in everyday life has been a subject of several Ambulatory Assessment studies. This mechanism has been studied in children, adults, and the elderly, but neglected in adolescents. It is critical to examine this mechanism in adolescents because adolescence plays a key role in human development and adolescents' physical activity behavior translates into their behavior in adulthood. We investigated adolescents' mood in relation to distinct physical activities: incidental activity such as climbing stairs; exercise activity, such as skating; and sports, such as playing soccer. We equipped 134 adolescents aged 12-17 years with accelerometers and GPS-triggered electronic diaries to use in their everyday life. Adolescents reported on mood repeatedly in real time across 7 days, and these data were analyzed using multilevel-modeling. After incidental activity, adolescents felt better and more energized. After exercise, adolescents felt better but less calm. After sports, adolescents felt less energized. Analyses of the time course of the effects confirmed our findings. Physical activity influences mood in adolescents' everyday life, but has distinct effects depending on the kind of physical activity. Our results suggest incidental and exercise activities entail higher post-bout valence compared to sports in competitive settings. These findings may serve as an important empirical basis for the targeted application of distinct physical activities to foster well-being in adolescence.

Testing the cross-stressor hypothesis under real-world conditions: exercise as a moderator of the association between momentary anxiety and cardiovascular responses

The cross-stressor adaptation hypothesis of exercise training has not been investigated under real-life conditions. Using ecological momentary assessment, we tested whether usual exercise level moderates the relationship of self-reported anxiety to concurrent ambulatory heart rate (HR) and systolic/diastolic blood pressure (SBP/DBP). Participants (N = 832) completed 24-h ambulatory monitoring of HR/BP, using a brachial BP cuff that took readings at 28-min intervals. Anxiety levels were concurrently reported on a visual analog scale (VAS) using a Palm Pilot. Usual exercise behavior was assessed by a self-report questionnaire. Random coefficients linear regression models predicting momentary HR/BP readings from time-matched anxiety scores were estimated, yielding the average within-person effect (slope) of anxiety. The interaction of exercise level (i.e., no weekly exercise, 1-149, and ≥ 150 min/week; a between-person factor) with anxiety was added to the model in order to estimate the average anxiety slope for participants in each exercise category. The relationship of HR/BP to anxiety did not differ significantly among exercise categories, hence not providing evidence for the cross-stressor hypothesis. In an exploratory analysis of the difference in HR/BP between occasions when anxiety was in the top versus bottom person-specific quintiles of responses, the difference in HR (but not SBP or DBP) varied significantly by exercise level (F(2,625) = 4.92, p = 0.008). Though our pre-specified analysis did not support the hypothesis, we provide some post hoc evidence supporting the cross-stressor hypothesis of exercise training for the HR response to anxiety.

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.

Accuracy of Sedentary Behavior-Triggered Ecological Momentary Assessment for Collecting Contextual Information: Development and Feasibility Study

BACKGROUND

Sedentary behavior has received much attention in the scientific community over the past decade. There is growing evidence that sedentary behavior is negatively associated with physical and mental health. However, an in-depth understanding of the social and environmental context of sedentary behavior is missing. Information about sedentary behavior, such as how everyday sedentary behavior occurs throughout the day (eg, number and length of sedentary bouts), where, when, and with whom it takes place, and what people are doing while being sedentary, is useful to inform the development of interventions aimed at reducing sedentary time. However, examining everyday sedentary behavior requires specific methods.

OBJECTIVE

The purpose of this paper is (1) to introduce sedentary behavior-triggered Ecological Momentary Assessment (EMA) as a methodological advancement in the field of sedentary behavior research and (2) to examine the accuracy of sedentary behavior-triggered EMA in 3 different studies in healthy adults. Moreover, we compare the accuracy of sedentary behavior-triggered EMA to simulations of random-trigger designs.

METHODS

Sedentary behavior-triggered EMA comprises a continuous assessment of sedentary behavior via accelerometers and repeated contextual assessments via electronic diaries (ie, an application on a smartphone). More specifically, the accelerometer analyzes and transfers data regarding body position (a sitting or lying position, or an upright position) via Bluetooth Low Energy (BLE) to a smartphone in real time and triggers the deployment of questionnaires. Each time a participant spends a specified time (eg, 20 minutes) in a sedentary position, the e-diary triggers contextual assessments. To test the accuracy of this method, we calculated a percentage score for all triggered prompts in relation to the total number of bouts that could trigger a prompt.

RESULTS

Based on the accelerometer recordings, 29.3% (5062/17278) of all sedentary bouts were classified as moderate-to-long (20-40 minutes) and long bouts (≥ 41 minutes). On average, the accuracy by participant was 82.77% (3339/4034; SD 21.01%, range 71.00-88.22%) on the study level. Compared to simulations of random prompts (every 120 minutes), the number of triggered prompts was up to 47.9% (n=704) higher through the sedentary behavior-triggered EMA approach. Nearly 40% (799/2001) of all prolonged sedentary bouts (≥ 20 minutes) occurred during work, and in 57% (1140/2001) of all bouts, the participants were not alone.

CONCLUSIONS

Sedentary behavior-triggered EMA is an accurate method for collecting contextual information on sedentary behavior in daily life. Given the growing interest in sedentary behavior research, this sophisticated approach offers a real advancement as it can be used to collect social and environmental contextual information or to unravel dynamic associations. Furthermore, it can be modified to develop sedentary behavior-triggered mHealth interventions.

Breaking Up Sedentary Behavior Optimally to Enhance Mood

INTRODUCTION

Experimental evidence shows that breaking-up sedentary behavior is positively associated with positive mental health outcomes. However, whether sedentary breaks influence mood in everyday life is largely unknown. Moreover, it is unclear which break patterns are most beneficial to enhance mood.

METHODS

To investigate the degree to which sedentary break patterns influence mood dimensions in everyday life, we conducted an Ecological Momentary Assessment study in 92 university employees over 5 d. We continuously measured physical behavior (physical activity and sedentary behavior) objectively via accelerometers and assessed mood 10 times a day on smartphone diaries. We defined distinct break patterns, such as variations in frequency (number of breaks), duration (length of breaks), intensity (metabolic equivalent), and context (home or work) and used multilevel modeling to analyze the within-subject effects of sedentary break patterns on mood.

RESULTS

Break intensity was positively associated with subsequent valence (P < 0.01), energetic arousal (P < 0.01), and calmness (P < 0.05). Break frequency was positively associated with subsequent valence and energetic arousal (all P's < 0.01), but break duration was not associated with mood. Exploratory analyses indicated that breaking-up sedentary behavior was more beneficial at home than at work.

CONCLUSIONS

These ecologically valid findings suggest breaking-up sedentary behavior as a promising strategy to enhance mood in everyday life. In particular, breaking-up sedentary behavior frequently and intensively, for example, by walking instead of standing, may be most beneficial. We call for future studies to substantiate these accounts and to identify both practical and optimal break patterns among different samples. This evidence informs official public health recommendations aiming to "minimize sedentary time in everyday life."

Exercise and Anxiety

Anxiety disorders are a group of highly prevalent mental health conditions that can have a debilitating impact on daily functioning and well-being. They can co-occur with other mental health disorders, such as depression. People with anxiety disorders are also at an elevated risk of cardiovascular disease and premature mortality. Physical activity appears to be protective against anxiety disorders in clinical and nonclinical populations. Exercise, a subset of physical activity, has been shown to significantly reduce the symptoms of anxiety. The mechanisms through which exercise produces these effects are likely to involve a combination of biological and psychological factors. Physical activity may also be useful in reducing the symptoms of comorbid mental health conditions and the risk of physical health complications over time. Promoting physical activity could be a method of preventing or treating anxiety disorders with a wide range of benefits. However, further research will be necessary to address important gaps in the literature before these approaches can be fully implemented in mental health services.

Does Cardiorespiratory Fitness Buffer Stress Reactivity and Stress Recovery in Police Officers? A Real-Life Study

High levels of cardiorespiratory fitness have the potential to buffer against physical and mental health impairments, which can result from exposure to occupational stress. Police officers are especially at risk of high psychosocial stress; therefore, effective intervention strategies are warranted. Given this background, the purpose of the present study was to examine whether police officers with different levels of cardiorespiratory fitness differ with regard to their (a) physiological stress reactivity during acute real-life stress situations, and (b) physiological recovery related to acute and chronic work stress. In total, 201 police officers took part in this study (M = 38.6 years, SD = 10.1, 35.8% females). Officers were contacted eight times on a smartphone during their workday, and asked to report their current level of positive and negative affect, as well as feelings of stress and anger. Physiological stress responses and recovery (heart rate variability) were assessed using Movisens EcgMove3 devices. The Åstrand bicycle ergometer test was used to assess participants' cardiorespiratory fitness. Chronic work stress was assessed using the effort-reward imbalance model and the job strain model. Multilevel modeling was used to test buffering effects of cardiorespiratory fitness on physiological stress reactivity. Linear regression was applied to test stress-buffering effects of cardiorespiratory fitness on physiological recovery. Results showed lowered physiological stress reactivity to acute work stress in officers with higher levels of cardiorespiratory fitness. However, these results were not consistent, with no effects occurring for feelings of anger, positive affect, and negative affect. Chronic work stress (effort-reward imbalance) was related to lower physiological recovery. Cardiorespiratory fitness was positively related to physiological recovery. Data did not support interactions between work stress and cardiorespiratory fitness on physiological recovery. To some extent, cardiorespiratory fitness seems to have the potential to buffer stress reactivity in police officers in acute stress situations. Therefore, we encourage promoting fitness programs which aim to enhance cardiorespiratory fitness in stressful occupations such as law enforcement. Improvements in cardiorespiratory fitness might further enhance physiological recovery from chronic work stress, which is thought to improve cardiovascular health.

Endurance Running Training Individually Guided by HRV in Untrained Women

da Silva, DF, Ferraro, ZM, Adamo, KB, and Machado, FA. Endurance running training individually guided by HRV in untrained women. J Strength Cond Res 33(3): 736-746, 2019-The aim of this study was to analyze the effects of heart rate variability (HRV)-guided training compared with a standardized prescription on (a) time to complete 5-km running performance (t5km), (b) peak treadmill running speed (Vpeak) and its time limit (tlim at Vpeak), and (c) autonomic cardiac modulation (i.e., parasympathetic activity and recovery) in untrained women. Additionally, we correlated changes in t5km with changes in Vpeak, tlim at Vpeak and autonomic cardiac modulation. Thirty-six untrained women were divided into a HRV-guided training group (HRVG) and a control group (CG). The CG followed a predefined program, alternating moderate-intensity continuous training (MICT) and high-intensity interval training (HIIT). The determination of MICT or HIIT was based on the pretraining HRV for HRVG. MICT was performed if HRV was <mean - 1 SD of previous measures. Otherwise, HIIT was prescribed. The t5km, Vpeak, tlim at Vpeak, parasympathetic activity (i.e., rMSSD) and parasympathetic reactivation (i.e., HRR) were measured before and after the training period. The t5km decreased to a greater magnitude in the HRVG (-17.5 ± 5.6% vs. -14 ± 4.7%; Effect Size (ES) between-group difference = moderate). rMSSD and tlim at Vpeak only improved in HRVG (+23.3 ± 27.8% and +23.6 ± 31.9%, respectively). The HRVG experienced greater improvements in Vpeak and HRR (Vpeak: 10 ± 7.3% vs. 8.2 ± 4.7%; HRR: 19.1 ± 28.1% vs. 12.6 ± 12.9%; ES between-group difference = small). Although HRVG performed less MICT than CG, the volume of MICT was negatively related to changes in t5km. Vpeak changes were highly correlated with t5km changes. The greater improvements in HRVG for t5km and autonomic modulation reinforce the potential application of this tool.

Does Cardiorespiratory Fitness Moderate the Association between Occupational Stress, Cardiovascular Risk, and Mental Health in Police Officers?

Background: Chronic exposure to occupational stress may lead to negative health consequences. Creating less stressful work environments and making employees physically and psychologically more resilient against stress are therefore two major public health concerns. This study examined whether cardiorespiratory fitness moderated the association between occupational stress, cardiovascular risk, and mental health. Methods: Stress was assessed via the Effort-Reward Imbalance and Job Demand-Control models in 201 police officers (36% women, Mage = 38.6 years). Higher levels of blood pressure, blood lipids, blood sugar, and unfavorable body composition were considered as cardiovascular risk factors. Burnout, insomnia and overall psychological distress were used as mental health indicators. Cardiorespiratory fitness was assessed with a submaximal bicycle test. Results: High cardiorespiratory fitness levels were associated with a reduced cardiometabolic risk, whereas high stress levels were associated with better mental health. Among participants who perceived a high Effort-Reward Imbalance, those with high fitness levels showed lower overall cardiovascular risk scores than their colleagues with low fitness levels. Conclusions: Work health programs for police officers should consider the early screening of burnout, sleep disturbances, and overall mental wellbeing. To increase cardiovascular health, including fitness tests in routine health checks and promoting physical activity to further increase cardiorespiratory fitness appears worthwhile.

Genetic, Physiologic, and Behavioral Predictors of Cardiorespiratory Fitness in Specialized Military Men

Introduction

Cardiorespiratory fitness (CRF) is a crucial performance requirement of specialized military occupations. Age and physical activity are established predictors of CRF, but it is not clear how these predictors combine with each other and/or with genetic predisposition. The goal of this study was to derive inclusive explanatory models of CRF in US Navy Explosive Ordnance Disposal (EOD) operators, synthesizing conventional (e.g., age, body composition, and physical activity) and novel influences (e.g., genetic variance).

Materials and Methods

In this cross-sectional study, 40 male, active duty EOD operators completed a graded exercise test to assess maximal oxygen consumption and ventilatory threshold (VT) using the Bruce protocol. Aerobic performance was further quantified via time of test termination and time at which VT was achieved. Body composition was determined via dual x-ray absorptiometry, and physical activity was assessed by self-report. Genetic variants underlying human stress systems (5HTTLPR, BclI, −2 C/G, and COMT) were assayed. Descriptive analyses were conducted to summarize subject characteristics. Hypotheses were tested with linear regression models. Specifically, separate univariate regression models first determined associations between each of the independent and dependent variables. This protocol was approved by the Naval Health Research Center Institutional Review Board (NHRC.2015.0013).

Results

In univariate regression models, age, body composition, physical activity, and 5HTTLPR consistently predicted CRF and/or aerobic performance (R2 range 0.07–0.55). Multivariate regression models routinely outperformed the univariate models, explaining 36–62% of variance.

Conclusion

This study signifies a shift toward inclusive explanatory models of CRF and aerobic performance, accounting for combined roles of genetic, physiologic, and behavioral influences. Although we were able to quantify combined effects, we were unable to evaluate interaction effects (e.g., gene–gene, gene–behavior) due to limited statistical power. Other limitations are that this specialized military population may not readily generalize to broader populations, and the current sample was all male. Considering these limitations, we aim to replicate this study in various populations, both male and female. Despite its limitations, this study reflects a shift toward more comprehensive predictive models of CRF, explaining the unique and shared contributions of genetic predisposition, physiology, and behavior. These findings have implications for assessment, selection, and training of specialized military members, and may also impact mission success and survivability. Future studies are needed to better characterize additive, interactive, and mediated effects.

Walking on treadmill with Rett syndrome-Effects on the autonomic nervous system

People with Rett syndrome have deficient central autonomic control, which may interfere with walking. We have limited knowledge regarding the effects of exertion during physical activity in Rett syndrome. The aim was to investigate the autonomic responses during walking on a treadmill in Rett syndrome. Twenty-six females, 12 with Rett syndrome and 14 healthy females were included. All individuals started on the treadmill by standing still, followed by walking slowly with progressive speed until reaching maximum individual speed, which they kept for 6 min. Heart rate (HR), systolic (SBP), diastolic (DBP), mean arterial blood pressures (MAP), cardiac vagal tone (CVT), cardiac sensitivity to baroreflex (CSB), transcutaneous partial pressures of oxygen (pO₂), carbon dioxide (pCO₂), and breathing movements were recorded simultaneously and continuously. Autonomic responses were assessed by MAP, CSB and CVT during walking at 3 and 6 min. The changes in CSB and CVT in people with Rett syndrome compared to controls indicated more arousal, but only when the treadmill was started; as they continued walking, the arousal dropped to control level. People with Rett syndrome exhibited little changes in pCO₂ whereas the controls showed increased values during walking. This suggests poor aerobic respiration in people with Rett syndrome during walking. Five people with Rett syndrome had Valsalva type of breathing at rest, three of those had normal breathing while walking on the treadmill while the remaining two started but soon stopped the Valsalva breathing during the walk. Our results show that individuals with Rett syndrome can walk for up to 6 min at their own maximum sustainable speed on a treadmill. Energy production may be low during walking in Rett syndrome, which could cause early tiredness. A treadmill can be used in people with Rett syndrome, but must be introduced slowly and should be individually tailored. We propose that walking promotes regular breathing in Rett syndrome.

High heart rate reactors display greater decreases in tear SIgA concentration following a novel acute stressor

Tear secretory immunoglobulin-A (SIgA) is a putative biomarker of common-cold risk with potential utility in non-invasive diagnostics. As SIgA secretion at the ocular surface is under strong autonomic control, we investigated the relationship between HR reactivity and tear SIgA responses to novel experiential stress. Thirty-two healthy participants undertook a 60 s zip-line ride to evoke acute stress and a seated-rest control trial in a randomised-crossover design. We recorded heart rate (HR) continuously and collected unstimulated tear samples 5 min pre-, 2 min post- and 20 min post-stress/control. Stress increased HR and state anxiety whereas tear SIgA concentration decreased 44% post-stress vs.

CONTROL

Higher peak HR values during stress uniquely explained 21% of the variance in tear SIgA reactivity to stress (p < 0.01); high HR reactors displayed greater decreases in tear SIgA concentration. We conclude that physiological arousal increases immune reactivity to acute stress and highlight tear SIgA as a minimally-invasive, physiologically relevant biomarker of immune reactivity.

Physical activity and negative affective reactivity in daily life

OBJECTIVE

The results from experimental studies indicate that physically active individuals remain calmer and report less anxiety after the induction of a standardized stressor. The current study extends this research to real life, and examines whether daily physical activity attenuates negative affect that occurs in response to naturally occurring daily stressors.

METHOD

The current study used data from the second wave of the National Study of Daily Experiences, a sub-study of the second wave of the Midlife in the United States Study (MIDUS-II) of 2,022 individuals aged 33-84 questioned nightly for eight consecutive days about their general affect and affective responses to stressful events and their engagement in physical activity.

RESULTS

Results indicated that while negative affect is significantly elevated on days with stressful events compared to days free of events in all individuals, these effects are attenuated in those who remain physically active when compared to those who were underactive. This was also true for any day participants were physically active. Importantly, negative affect in response to any specific stressor was reduced the closer in time that the stressor occurred to the bout of exercise in underactive participants, while, in active participants, negative affect in response to any stressor remained low throughout the entire day that participants reported that they were active.

CONCLUSION

Given the significant mental and physical health implications of elevated affective reactivity observed in previous studies, the current study sheds further light on the importance of remaining physically active in times of stress. (PsycINFO Database Record

Physical Activity Modulates Common Neuroplasticity Substrates in Major Depressive and Bipolar Disorder

Mood disorders (MDs) are chronic, recurrent mental diseases that affect millions of individuals worldwide. Although the biogenic amine model has provided some clinical utility, a need remains to better understand the interrelated mechanisms that contribute to neuroplasticity deficits in MDs and the means by which various therapeutics mitigate them. Of those therapeutics being investigated, physical activity (PA) has shown clear and consistent promise. Accordingly, the aims of this review are to (1) explicate key modulators, processes, and interactions that impinge upon multiple susceptibility points to effectuate neuroplasticity deficits in MDs; (2) explore the putative mechanisms by which PA mitigates these features; (3) review protocols used to induce the positive effects of PA in MDs; and (4) highlight implications for clinicians and researchers.

Presenteeism, stress resilience, and physical activity in older manual workers: a person-centred analysis

This study used a person-centred approach to explore typologies of older manual workers based on presenteeism, stress resilience, and physical activity. Older manual workers (n = 217; 69.1% male; age range 50-77; M age = 57.11 years; SD = 5.62) from a range of UK-based organisations, representing different manual job roles, took part in the study. A cross-sectional survey design was used. Based on the three input variables: presenteeism, stress resilience and physical activity, four distinct profiles were identified on using Latent Profile Analysis. One group ('High sport/exercise and well-functioning'; 5.50%) engaged in high levels of sport/exercise and exhibited low levels of stress resilience and all types of presenteeism. Another profile ('Physically burdened'; 9.70%) reported high levels of work and leisure-time physical activity, low stress resilience, as well as high levels of presenteeism due to physical and time demands. A 'Moderately active and functioning' group (46.50%) exhibited moderate levels on all variables. Finally, the fourth profile ('Moderately active with high presenteeism'; 38.20%) reported engaging in moderate levels of physical activity and had relatively high levels of stress resilience, yet also high levels of presenteeism. The profiles differed on work affect and health perceptions largely in the expected directions. There were no differences between the profiles in socio-demographics. These results highlight complex within-person interactions between presenteeism, stress resilience, and physical activity in older manual workers. The identification of profiles of older manual workers who are at risk of poor health and functioning may inform targeted interventions to help retain them in the workforce for longer.