Diurnal patterns of salivary alpha-amylase and cortisol secretion in female adolescent tennis players after 16 weeks of training

Eight weeks of high-intensity interval training versus stretching do not change the psychoneuroendocrine response to a social stress test in emotionally impulsive humans

PURPOSE

Research supports physical activity as a method to heighten stress resistance and resilience through positive metabolic alterations mostly affecting the neuroendocrine system. High-intensity interval training (HIIT) has been proposed as a highly effective time-saving method to induce those changes. However, existing literature relies heavily on cross-sectional analyses, with few randomised controlled trials highlighting the necessity for more exercise interventions. Thus, this study aims to investigate the effects of HIIT versus an active control group on the stress response to an acute psychosocial stressor in emotionally impulsive humans (suggested as being strong stress responders).

METHODS

The study protocol was registered online (DRKS00016589) before data collection. Sedentary, emotionally impulsive adults (30.69 ± 8.20 y) were recruited for a supervised intervention of 8 weeks and randomly allocated to either a HIIT (n = 25) or a stretching group (n = 19, acting as active controls). Participants were submitted to a test battery, including saliva samples, questionnaires (self-efficacy- and perceived stress-related), visual analogue scales (physical exercise- and stress-related), and resting electroencephalography and electrocardiography assessing their reaction to an acute psychological stressor (Trier Social Stress Test) before and after the exercise intervention.

RESULTS

HIIT increased aerobic fitness in all participants, whereas stretching did not. Participants from the HIIT group reported perceiving exercising more intensively than those from the active control group (ƞp2 = 0.108, p = 0.038). No further group differences were detected. Both interventions largely increased levels of joy post-TSST (ƞp2 = 0.209, p = 0.003) whilst decreasing tension (ƞp2 = 0.262, p < 0.001) and worries (ƞp2 = 0.113, p = 0.037). Finally, both interventions largely increased perceived levels of general self-efficacy (ƞp2 = 0.120, p = 0.029).

CONCLUSION

This study suggests that 8 weeks of HIIT does not change the psychoneuroendocrine response to an acute psychological stress test compared to an active control group in emotionally impulsive humans. Further replications of supervised exercise studies highly powered with active and passive controls are warranted.

Recent advances in understanding the neurobiology of pediatric functional neurological disorder

INTRODUCTION

Functional neurological disorder (FND) is a neuropsychiatric disorder that manifests in a broad array of functional motor, sensory, or cognitive symptoms, which arise from complex interactions between brain, mind, body, and context. Children with FND make up 10%-20% of presentations to neurology services in children's hospitals and up to 20% of adolescents admitted to hospital for the management of intractable seizures.

AREAS COVERED

The current review focuses on the neurobiology of pediatric FND. The authors present an overview of the small but growing body of research pertaining to the biological, emotion-processing, cognitive, mental health, physical health, and social system levels.

EXPERT OPINION

Emerging research suggests that pediatric FND is underpinned by aberrant changes within and between neuron-glial (brain) networks, with a variety of factors - on multiple system levels - contributing to brain network changes. In pediatric practice, adverse childhood experiences (ACEs) are commonly reported, and activation or dysregulation of stress-system components is a frequent finding. Our growing understanding of the neurobiology of pediatric FND has yielded important flow-on effects for assessing and diagnosing FND, for developing targeted treatment interventions, and for improving the treatment outcomes of children and adolescents with FND.

Assessment of salivary cortisol dynamics in an infantry training exercise: a pilot study

INTRODUCTION

Measuring cortisol during military training offers insights into physiological responses to stress. We attempted precisely timed, cortisol awakening response (CAR) and pre-sleep cortisol (PSC), and diurnal slope (peak morning minus evening cortisol), during a British Army exercise. We aimed to understand cortisol dynamics and evaluate the feasibility of CAR and PSC in this environment.

METHOD

Setting: high-intensity, 10-day infantry exercise. Participants: regular infantry soldiers exercising (EX, n=25) or headquarters-based (HQ, n=6). Participants undertook PSC and WAKE and WAKE+30 min samples after 1-2 days, 5-6 days and 9-10 days. Wrist-worn GENEActiv accelerometers were used to assess sleep duration in EX only. Samples taken ±15 min from prespecified time points were deemed adherent. Validated questionnaires were used to measure resilience and perceived stress. Cortisol and cortisone were measured simultaneously by liquid chromatography tandem mass spectrometry.

RESULTS

From adherent participants' samples, CAR was positive and tended to decrease as the exercise progressed. From all available data, HQ demonstrated greater diurnal slope than EX (F=7.68, p=0.02), reflecting higher morning cortisol (F=4.72, p=0.038) and lower PSC (p=0.04). No differences were seen in cortisol:cortisone ratio. 26.1% of CAR samples were adherent, with moderately strong associations between adherence and stress (r=0.41, p=0.009) but no association between adherence and day of exercise (χ2=0.27, p=0.8), sleep duration (r=-0.112, p=0.43) or resilience (r=-0.79, p=0.75). Test-retest reliability ratings for CAR were Cronbach's α of 0.48, -11.7 and 0.34 for the beginning, middle and end of the exercise, respectively.

CONCLUSIONS

We observed a reduction in morning cortisol and decreased diurnal slope during a high-intensity military exercise, compared with the HQ comparator cohort in whom diurnal slope was preserved. A carefully timed CAR was not feasible in this setting.

Physical Activity and Cortisol Regulation: A Meta-Analysis

Physical activity participation is associated with effective stress coping, indicated by decreases in both physiological stress reactivity and perceived stress. Quantifying the effect of physical activity on the diurnal regulation of one key physiological stress indicator, the stress hormone, cortisol, across studies may demonstrate the extent to which physical activity participation is associated with diurnal HPA axis regulation. We meta-analyzed studies examining relations between physical activity participation and indices of HPA axis regulation: the diurnal cortisol slope and the cortisol awakening response. We also examined moderators of the relation. The analysis revealed a small, non-zero negative averaged correlation between physical activity and the diurnal cortisol slope (r = -0.043, 95% CI [-0.080, -0.004]). Examination of sample sociodemographic differences, study design characteristics, cortisol measurement methods, and physical activity variables as moderators revealed few effects on the relation between physical activity and diurnal cortisol slope. We did not observe lower levels of variability in the mean cortisol awakening response at higher levels of physical activity participation, and moderator analyses showed little evidence of reductions in heterogeneity for this effect. We found some evidence of systematic publication bias. Findings suggest higher physical activity is associated with a steeper diurnal cortisol slope. However, the cortisol awakening response did not differ by physical activity level. Future studies testing the physical activity and cortisol regulation association should use standardized physical activity measures, follow guidelines for better quality cortisol sampling collection and analysis, and test relations in large-scale empirical studies to confirm the direction and causality of the effect.

Cortisol and α-amylase awakening response in children and adolescents with functional neurological (conversion) disorder

OBJECTIVE

Stress system dysregulation is considered to have an important role in the aetiology of paediatric functional neurological (conversion) disorder. This study examined salivary cortisol and α-amylase awakening responses in children with functional neurological disorder to determine activation patterns of the hypothalamic-pituitary-adrenal axis and sympathetic system. A healthy cortisol awakening response involves a robust increase in cortisol within 30 minutes of awakening. Alpha-amylase awakening response is variable in children.

METHODS

Cortisol and α-amylase were measured in saliva from 32 patients with functional neurological disorder (26 girls and 6 boys, aged 11.3-16.1 years) and 31 healthy controls (23 girls and 8 boys, aged 8.6-17.7 years). Saliva samples were collected using a Salivette sampling device at two time points - upon awakening and 30 minutes after awakening.

RESULTS

Patients with functional neurological disorder showed a decrease in cortisol awakening response (-4 nmol.min/L) and controls showed an increase (107 nmol.min/L), t(55) = -.4.6, p < 0.001. Within the functional neurological disorder group, 57% showed an attenuated cortisol awakening response and 43% showed an obliterated/reversed cortisol awakening response: Cortisol awakening response was negatively correlated with adverse childhood experiences, r(58) = -0.6, p = 0.002, and subjective distress (total Depression Anxiety and Stress Scales score), r(58) = -0.4, p = 0.050. In controls, cortisol awakening response showed no correlation with adverse childhood experiences and a positive correlation with subjective distress, r(56) = 0.4, p = 0.023. Total cortisol remained similar between the functional neurological disorder and control group. No significant differences were observed between the functional neurological disorder and control group in any of the α-amylase analyses.

DISCUSSION

The results suggest dysregulation of the hypothalamic-pituitary-adrenal axis in children with functional neurological disorder. Hypothalamic-pituitary-adrenal dysregulation in children with functional neurological disorder may contribute to comorbid symptoms of fatigue, sleep disturbance and subjective loss of well-being because circadian rhythms and energy metabolism are disrupted. Hypothalamic-pituitary-adrenal dysregulation - and changes in glucocorticoid (cortisol) signalling at the molecular level - may also contribute to increased vulnerability for functional neurological disorder symptoms because of epigenetically mediated changes to neural networks implicated in functional neurological disorder.

Regulatory Mechanisms of Muscle Mass: The Critical Role of Resistance Training in Children and Adolescent

Muscle mass and strength are subjected to several regulations. We found endocrine signals such as growth hormone, insulin-like growth factor 1, testosterone, thyroid hormones, and glucocorticoids among them. Neural inputs also influence muscle development, modulating mass and strength. Among the external stimuli that modulate these muscular features is physical training such as resistance and endurance training. Specifically, resistance training can mediate an increase in muscle mass by hypertrophy in adults, but the effects in children and adolescents are full of myths for most of the population. However, the evidence shows that the impact of resistance training on children and adolescents is clear and provides a wide range of benefits. However, qualified professionals must be available since exercise prescription and subsequent supervision must follow this population's abilities, needs, and interests.

Altered resting-state neural networks in children and adolescents with functional neurological disorder

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FND in children commonly involves presentation with multiple neurological symptoms.

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Children with FND show wide-ranging connectivity changes in resting-state neural networks.

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Aberrant neural-networks changes are greater in children whose FND includes functional seizures.

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Subjective distress, autonomic arousal, and HPA dysregulation contribute to network changes.

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Children with FND (vs controls) report more subjective distress and more ACEs across the lifespan.

Objectives

Previous studies with adults suggest that aberrant communication between neural networks underpins functional neurological disorder (FND). The current study adopts a data-driven approach to investigate the extent that functional resting-state networks are disrupted in a pediatric mixed-FND cohort.

Methods

31 children with mixed FND and 33 age- and sex-matched healthy controls completed resting-state fMRI scans. Whole-brain independent component analysis (pFWE < 0.05) was then used to identify group differences in resting-state connectivity. Self-report measures included the Depression, Anxiety and Stress Scale (DASS-21) and Early Life Stress Questionnaire (ELSQ). Resting-state heart rate (HR) and cortisol-awakening response (CAR) were available in a subset.

Results

Children with FND showed wide-ranging connectivity changes in eight independent components corresponding to eight resting-state neural networks: language networks (IC6 and IC1), visual network, frontoparietal network, salience network, dorsal attention network, cerebellar network, and sensorimotor network. Children whose clinical presentation included functional seizures (vs children with other FND symptoms) showed greater connectivity decreases in the frontoparietal and dorsal attentional networks. Subjective distress (total DASS score), autonomic arousal (indexed by HR), and HPA dysregulation (attenuated/reversed CAR) contributed to changes in neural network connectivity. Children with FND (vs controls) reported more subjective distress (total DASS score) and more adverse childhood experiences (ACEs) across their lifespan.

Conclusions

Children with FND demonstrate changes in resting-state connectivity. Identified network alterations underpin a broad range of functions typically disrupted in children with FND. This study complements the adult literature by suggesting that FND in children and adolescents emerges in the context of their lived experience and that it reflects aberrant communication across neural networks.

Mental fatigue increases across a 16-week pre-season in elite female athletes

OBJECTIVES

To examine potential changes in mental and physical fatigue across an elite netball pre-season training phase and relationships between mental fatigue, physical fatigue, salivary cortisol (sCort) and alpha-amylase (sAA).

DESIGN

Observational with repeated measures.

METHODS

Across a 16-week pre-season, 10 elite female netballers (25.3 ± 3.7y) rated their physical fatigue, mental fatigue and readiness to perform on 100-mm visual analogue scales, and provided salivary samples for sCort and sAA analyses.

RESULTS

Linear mixed model analyses revealed elevated (p < 0.05) ratings of mental fatigue for weeks 12, 14 and 15 v 1; 12, 14 and 15 v 4 and 14 v 7. Higher (p < 0.05) ratings of physical fatigue were reported on weeks 6, 10, 11 and 12-16 compared to week 4; and 10 and 13 compared to week 7. Moderate and large ES differences were found between multiple weeks. Mental and physical fatigue demonstrated a shared variance of 14.3% (r = 0.38, p < 0.001) and an inverse relationship was observed between mental fatigue and readiness to perform (r = -0.50; p < 0.001). Changes in sCort nor sAA were not related to changes in mental or physical fatigue.

CONCLUSIONS

Mental fatigue fluctuated across the 16-week pre-season phase with elevated ratings observed in the later weeks. Whilst value remains in identifying subjective tools to assess mental fatigue; salivary biomarkers do not appear to be a suitable objective indicator of mental fatigue in the applied sporting environment. Practitioners should work to identify and manage mental fatigue with the same level of importance given to the periodisation of physical fatigue.

Relationship of Choroidal Vasculature and Choriocapillaris Flow With Alterations of Salivary α-Amylase Patterns in Central Serous Chorioretinopathy

Purpose

An abnormality in choroidal vasculature is a known factor in the pathogenesis of central serous chorioretinopathy (CSC), a chorioretinal disease affecting mostly middle-aged males. The purpose of the present study was to investigate the role of the autonomic nervous system (ANS) in the pathophysiology of CSC.

Methods

This was a cross-sectional observational study in which characteristic choroidal vasculature metrics were assessed by measuring the subfoveal choroidal thickness (FCT) and the choroidal vascularity index (CVI) using the imaging technique of enhanced-depth imaging spectral-domain optical coherence tomography (EDI-SD-OCT). Furthermore, flow signal void area features were also evaluated in the study population using OCT angiography (OCTA). Diurnal patterns of salivary α-amylase (a-AMY) production, proposed as a marker of autonomic activity, were assessed in an adult male study population affected by acute naïve CSC in comparison with matched healthy controls.

Results

Results include an overall higher diurnal output of salivary a-AMY production, which is in line with the phenomenon of a sympathetic “drive” playing a role in the pathophysiology of CSC, and a flattened diurnal percentage variation in α-AMY in CSC-affected subjects. Furthermore, Pearson's coefficient test revealed statistically significant correlations between salivary α-AMY diurnal percentage variation and selected choroidal imaging biomarkers (FCT, CVI, and flow signal void area). Finally, multiple linear regression analysis identified salivary α-AMY diurnal percentage production as the sole predictor of the CVI and flow signal void area in the study population.

Conclusions

Autonomic nervous system dysregulation was highlighted in CSC patients.

Toward a neuroprotective shift: Eight weeks of high intensity interval training reduces the neurotoxic kynurenine activity concurrently to impulsivity in emotionally impulsive humans - A randomized controlled trial

BACKGROUND

Previous findings suggest that impulsivity is related to chronic low-grade inflammation. Inflammation is known to trigger the kynurenine pathway to a pathological level in various impulsivity-related disorders. Nonetheless, murine models and recent human studies have shown that physical exercise, in particular High Intensity Interval Training (HIIT), could counterbalance the negative effects of inflammation on the kynurenine pathway.

AIM

This study evaluates the effects of eight weeks of HIIT versus an active control group on impulsivity levels and accompanying alterations of inflammatory-mediated changes of the kynurenine pathway in a sample of emotionally impulsive humans.

METHODS

Participants were randomly allocated to either HIIT or stretching conditions (three trainings per week for eight weeks). Fitness level was evaluated via VO₂peak values at the beginning at end of the intervention. Kynurenine metabolites, pro-inflammatory cytokines, and impulsivity levels were evaluated at T0, T4, and T8 weeks. Statistical analyses were performed using mixed models.

RESULTS

Fifty-three participants were included in the modified Intention To Treat analysis (45 finished the intervention). The HIIT group (n = 28) largely increased the aerobic fitness of its participants and produced physiological changes while the stretching group (n = 25) did not. HIIT reduced interleukin 6 levels (small to moderate interaction) and reduced the activity of the neurotoxic branch of the kynurenine pathway (small to moderate interaction for KYNA/QA and KYN/QA) after eight weeks of training while the active control did not change. Both interventions were effective to decrease emotion-related impulsivity, however only the HIIT group decreased participants' emotion-unrelated levels. Changes in emotion-related and -unrelated impulsivity were moderately correlated to changes in KYNA/KYN.

CONCLUSION

This study demonstrated that HIIT was able to switch the kynurenine pathway from its neurotoxic branch to its neuroprotective one. This shift was associated with a decrease in impulsivity. Based on these findings, future work may consider investigating more intensively the effect of HIIT on impulsivity-related disorders.

Competitive anxiety or Coronavirus anxiety? The psychophysiological responses of professional football players after returning to competition during the COVID-19 pandemic

OBJECTIVE

This study aimed to examine the relationship between competitive anxiety, fear/anxiety of COVID-19, and autonomic and endocrine stress responses in professional football players after returning to competition during the COVID-19 pandemic.

METHODS

Ninety male professional football players (age: 26.33 ± 2.48 yr) volunteered to participate in this study, which included an official competition. Psychophysiological responses, including the Fear of COVID-19 Scale, the Coronavirus Anxiety Scale, and the Competitive State Anxiety Inventory-2 Revised, were collected 30 min before the competition. In addition, salivary alpha-amylase (sAA) and salivary cortisol (sCort) were collected at 8 a.m. and 15 min before the competition.

RESULTS

The main findings, based on the Pearson correlation, showed significant positive correlations between COVID-19 anxiety and somatic competitive anxiety (p = 0.01), cognitive competitive anxiety (p = 0.01), and competition response of sCort and sAA (p = 0.01). Moreover, fear of COVID-19 was positively correlated with COVID-19 anxiety (p = 0.01). On the contrary, the awakening response of sCort and sAA was not found to be correlated with psychological parameters (all p > 0.05). The analysis also indicated that there was no significant correlation between self-confidence with other psychological and physiological variables (all p > 0.05). The regression analysis showed that cognitive anxiety was a relevant predictor for the competition response of sCort and sAA (p < 0.05). Moreover, COVID-19 anxiety was the only predictor of somatic and cognitive anxiety (p < 0.05).

CONCLUSIONS

The present study provides the first preliminary evidence that COVID-19 anxiety and competitive anxiety might pose a negative impact on the athletic performance of professional football players during COVID-19 pandemic competitions. Thus, research is needed to build a strategy to reduce the psychophysiological stress related to COVID-19 and competition response.

Resistance training as an acute stressor in healthy young men: associations with heart rate variability, alpha-amylase, and cortisol levels

Regular resistance training has been shown to have many physiological and psychological health benefits. However, the underlying physiological processes are not yet fully understood. One explanation is that resistance training acts like an acute stressor and modulates physiological pathways that are associated with the stress response such as the sympathetic nervous system (SNS), the parasympathetic nervous system (PNS), and the hypothalamic-pituitary-adrenal (HPA) axis. This was systematically investigated in our study. Participants were 45 healthy men who had been doing resistance training regularly for at least nine months. Salivary α-amylase and heart rate that were used as markers for SNS activity increased during the training and decreased afterwards. PNS activity that was assessed by means of heart rate variability parameters decreased during the training and increased after it. Salivary cortisol that was used as marker for HPA axis activity decreased throughout the session. Furthermore, an improvement of positive affect was found after the training. However, additional analyses indicated that the physiological response patterns were found for participants who chose upper-body exercises (in contrast to lower-body exercises) only. Therefore, we were able to show that an upper-body resistance training acts partially like an acute stressor which leads to the typical SNS and PNS - but not HPA axis - stress responses. We conclude that resistance trainings might be an alternative to classical relaxation programs which would have the additional advantage that it is a physical training at the same time. However, more research is needed to develop specific trainings which entirely fulfill this goal.

Psychological and Physiological Features Associated with Swimming Performance

BACKGROUND

The aim of the present research was to study the psychological and physiological features associated with aerobic and anaerobic performance in trained swimmers.

METHODS

A correlation and stepwise regression analyses were conducted with the data obtained in a RESTQ-76 sport questionnaire, a heart rate variability test, and an anaerobic and aerobic swimming performance efforts of 20 swimmers.

RESULTS

Aerobic performance correlated, principally, with parameters related to parasympathetic modulation measured in the frequency and time domains of the heart rate variability (LF/HF r: -0.806, p < 0.001; NN50 r: 0.937, p < 0.001). Swimmers' anaerobic performance correlated to psychological features (low stress r: 0.526, p: 0.025, and high fatigue r: -0.506, p: 0.032).

CONCLUSION

Swimming performance presented different psychological and physiological features depending on the probe characteristic. Specifically, swimmers' anaerobic performance was associated with psychological features (low stress and high fatigue perception) and aerobic performance with physiological features (high parasympathetic modulation). This information could help coaches to know the variables to control in their swimmers, depending on the probe in which they compete (anaerobic or aerobic).

The Stress of Competing: Cortisol and Amylase Response to Training and Competition

TeamGym is a popular form of gymnastics, including tumbling (Tu), trampette (Tr) and floor exercises (F) characterized by intensive practice placing high levels of stress on athletes. The aim of the study was to investigate athletes' stress-related changes during TeamGym training and competition, considering hormonal and enzymatic responses (i.e., salivary cortisol and alpha-amylase). Ten (5 males and 5 females) TeamGym athletes (age: 22-28 y) were tested twice at the same time before training and competition; furthermore, for excluding circadian effect on hormonal and enzymatic responses, they were tested at the same time during a rest day. Alpha-amylase and cortisol were measured 15 min before the beginning of exercise, after each gymnastic equipment performance, and after thirty minutes from the end of the performance. Factorial ANOVA with repeated measures was used to verify differences between training and competition (p < 0.05). Competition elicited higher values of alpha-amylase than training (p ranging from 0.001 to 0.019) and rest (p ranging from 0.001 to 0.019). Cortisol showed no exercise induced increase, and its concentrations were higher prior to training compared to competition. TeamGym responses confirm other sports findings in stating that competition elicits higher stress response than training and suggest that salivary alpha-amylase is a more sensitive marker than cortisol to psychophysiological stress also in gymnastics intermittent performance.

Sleep quality monitoring in individual sports athletes: parameters and definitions by systematic review

In the present review, we identify which instruments and parameters are used for sleep quality monitoring in individual sport athletes and which definitions were used for sleep quality parameters in this literature field. Systematic searches for articles reporting the qualitative markers related to sleep in team sport athletes were conducted in PubMed, Scopus and Web of Science online databases. The systematic review followed the Preferred Reporting Items for Systematic Reviews. The initial search returned 3316 articles. After the removal of duplicate articles, eligibility assessment, 75 studies were included in this systematic review. Our main findings were that the most widely used measurement instruments were Actigraphy (25%), Rating Likert Scales (16%) and Sleep Diary (13%). On sleep quality parameters (Sleep duration = 14%; Wake after sleep onset = 14%; Sleep Quality = 12%; Sleep Effciency = 11% and Sleep Latency = 9%), the main point is that there are different definitions for the same parameters in many cases reported in the literature. We conclude that the most widely used instruments for monitoring sleep quality were Actigraphy, Likert scales and Sleep diary. Moreover, the definitions of sleep parameters are inconsistent in the literature, hindering the understanding of the sleep-sport performance relationship.

Increase in subjective well-being and psychological health after application of C8-silk lipoamino acid functionalized pigments included in a foundation

OBJECTIVE

The aim of this study was to evaluate the effects of two foundations before (D0) and after 5 days of application (D6) on psychophysiological parameters in order to compare C8-silk lipoamino acid functionalized pigments (FA) versus pure pigments (FP).

METHODS

Assessment of self-esteem, stress, mood and emotion using psychological tests and evaluation of salivary cortisol concentrations were realized on 40 healthy females using a crossover study design at D0 and D6. Four saliva samples were taken on the awakening (C1), 30 min after the awakening (during the foundation application (C2)), 1 h after the foundation application (C3) and at 1900 h (C4) at DO and D6. Area under the curve was calculated in order to obtain information about the total amount of a given substance excreted in a specific time period.

RESULTS

Five days of daily application of the foundation containing the pigments treated with the C8-silk lipoamino acids induced a significant increase (P < 0.001) in self-esteem and pleasant emotion (P < 0.05), and a significant decrease in general stress (P < 0.05). This was not the case after the FP application. Cortisol concentrations presented a pronounced diurnal rhythm whatever the foundation used. At DO, no significant differences were observed between the groups. At D6, cortisol concentrations measured 30 min and 1 h after the FA application were significantly lower (P < 0.05: C6.2, P < 0.05 C6.3, respectively) than those reported after FP application. AUC, a global stress response indicator, was significantly lower in FA group as compared to FP group after 5 days of application. Subjects found a decrease in tiredness signs and thought that FA has a good coverage.

CONCLUSION

Our results show that incorporation of C8-silk lipoamino acid as agent of pigment functionalization brings new benefits to a foundation. Adopting a psychophysiological approach, which is not invasive to the subjects, we show the measurement of cortisol at the same time that psychological indicators provide a scientific approach to examine the beneficial effects of a cosmetic product.

Attentional blink affected by acute stress in women: The role of affective stimuli and attentional resources

The role of attentional resources and affective stimuli on temporal selective attention in the rapid serial visual presentation (RSVP) paradigm under acute stress was explored among women. Seventy-three female undergraduates were randomly assigned to the Trier Social Stress Test (TSST) group or control group. We found that when the first target was negative, stress increased its accuracy. Stress promoted the recognition of neutral target two (T2) only at lag2, and there was no interaction with theemotionality of target one (T1). In addition, the accumulated effect of stress enhanced temporal selective attention, predominately 20-40 min after the TSST task; cortisol concentration during this time period could significantly predict AB task performance. In summary, when attentional resources were severely insufficient, individuals under stress were more able to focus on the current target; that is, stress facilitated selective attention. A novel result was that participants were exempt from the affective influence of previous targets, which may have been caused by activation of the autonomic nervous system and gender differences.

Heart Rate Variability in Sport Performance: Do Time of Day and Chronotype Play A Role?

A reliable non-invasive method to assess autonomic nervous system activity involves the evaluation of the time course of heart rate variability (HRV). HRV may vary in accordance with the degree and duration of training, and the circadian fluctuation of this variable is crucial for human health since the heart adapts to the needs of different activity levels during sleep phases or in the daytime. In the present review, time-of-day and chronotype effect on HRV in response to acute sessions of physical activity are discussed. Results are sparse and controversial; however, it seems that evening-type subjects have a higher perturbation of the autonomic nervous system (ANS), with slowed vagal reactivation and higher heart rate values in response to morning exercise than morning types. Conversely, both chronotype categories showed similar ANS activity during evening physical tasks, suggesting that this time of day seems to perturb the HRV circadian rhythm to a lesser extent. The control for chronotype and time-of-day effect represents a key strategy for individual training schedules, and, in perspective, for primary injury prevention.

Monitoring stress and recovery states: Structural and external stages of the short version of the RESTQ sport in elite swimmers before championships

BACKGROUND

Psychological stress and recovery monitoring is a key issue for increasing athletes' health, well-being, and performance. This multi-study report examined changes and the dose-response relationships between recovery-stress psychological states, training load (TL), heart rate (HR), heart rate recovery (HRR), and heart rate variability (HRV) while providing evidence for the factorial validity of a short French version of the Recovery-Stress Questionnaire for Athletes (RESTQ-36-R-Sport).

METHODS

Four hundred and seventy-three university athletes (Study 1), 72 full expert swimmers (Study 2), and 11 national to international swimmers (Study 3) participated in the study. Data were analyzed through confirmatory factor analyses (Study 1), repeated ANOVAs and correlational analyses (Study 2), t tests and correlational analyses (Study 3).

RESULTS

Multiple-group confirmatory factor analyses showed that the RESTQ-36-R-Sport scores were partially invariant across gender, type of sport, and practice level (Study 1). A dose-response relationship was performed between TL and RESTQ-36-R-Sport scores during an ecological training program (Study 2). Finally, relationships were found between physiological (HRR) and psychological (RESTQ-36-R-Sport) states during an ecological tapering period leading to a national championship (Study 3).

CONCLUSION

As a whole, these findings provided evidence for the usefulness of the short version of the RESTQ-36-R-Sport for regular monitoring to prevent potential maladaptation due to intensive competitive sport practice.

Realising the Potential of Urine and Saliva as Diagnostic Tools in Sport and Exercise Medicine

Accurate monitoring of homeostatic perturbations following various psychophysiological stressors is essential in sports and exercise medicine. Various biomarkers are routinely used as monitoring tools in both clinical and elite sport settings. Blood collection and muscle biopsies, both invasive in nature, are considered the gold standard for the analysis of these biomarkers in exercise science. Exploring non-invasive methods of collecting and analysing biomarkers that are capable of providing accurate information regarding exercise-induced physiological and psychological stress is of obvious practical importance. This review describes the potential benefits, and the limitations, of using saliva and urine to ascertain biomarkers capable of identifying important stressors that are routinely encountered before, during, or after intense or unaccustomed exercise, competition, over-training, and inappropriate recovery. In particular, we focus on urinary and saliva biomarkers that have previously been used to monitor muscle damage, inflammation, cardiovascular stress, oxidative stress, hydration status, and brain distress. Evidence is provided from a range of empirical studies suggesting that urine and saliva are both capable of identifying various stressors. Although additional research regarding the efficacy of using urine and/or saliva to indicate the severity of exercise-induced psychophysiological stress is required, it is likely that these non-invasive biomarkers will represent "the future" in sports and exercise medicine.

The salivary alpha amylase awakening response is related to over-commitment

We assessed the relationship between physiological and psychological measures of workplace stress as measured by the effort-reward imbalance (ERI) model, with a seldom studied sample of owner-operator dairy farmers. Dairy farmers (N = 74) self-reported ERI, over-commitment (OC), dedication, and health then provided awakening saliva samples that were used to calculate the salivary alpha amylase awakening response (sAA-AR), cortisol awakening response (CAR), and salivary immunoglobulin A (sIgA) level. ERI, OC, and dedication levels were not related with sIgA or the CAR, but more over-committed farmers had a less pronounced sAA-AR. OC was more associated than ERI with the physiological indicators of stress, potentially due to the owner-operator sample used in this investigation. The suitability of sAA as a viable physiological measure of autonomic nervous system activity has been debated, but our findings promote its inclusion in future occupational stress research.

Capturing effort and recovery: reactive and recuperative cortisol responses to competition in well-trained rowers

Background/aim

It is well known that physical strain is associated with increased cortisol production. And although mental stress elevates cortisol concentrations as well, little is known of the independent and/or combined effects of both on the secretion of cortisol. Aim of the study was to investigate the day-to-day cortisol dynamics associated with training, performance and recuperation and the immediate responses to mental stress and physical endurance under competitive conditions.

Methods

Sixteen freshmen competitive male rowers were prospectively followed from Thursday to Tuesday with an intermediate competition on Saturday and Sunday. On all days, three saliva samples were collected within 30 min after awakening to assess the cortisol awakening rise (CAR). Additionally, five saliva samples were collected previously to and immediately after all races during the regatta weekend.

Results

CAR values peaked during competition days and recovered during the 2 days after. Cortisol concentrations significantly increased during and after all races. Furthermore, although response patterns did not differ, the morning races showed significantly higher cortisol levels compared with the levels measured during the afternoon races. This likely reflects the normal diurnal rhythm of corticosteroids.

Conclusions

These results indicate that cortisol levels of athletes might be sensitive for both immediate responses to competition and, in case of CAR, (midterm) recovery phasing. Consequently, monitoring cortisol responses during training and competition may provide valuable information regarding how athletes cope with competition-induced stress and their recovery status during the days following. This insight might help to plan future training loads and recovery.

Hyperactivity of the Sympatho-Adrenomedullary System Without Any Modification of the Hypothalamic-Pituitary-Adrenal Axis After Food Restriction Among High-Level Weightlifters

Durguerian, A, Filaire, E, Drogou, C, Sauvet, F, Bougard, C, and Chennaoui, M. Hyperactivity of the sympatho-adrenomedullary system without any modification of the hypothalamic-pituitary-adrenal axis after food restriction among high-level weightlifters. J Strength Cond Res 32(6): 1643-1655, 2018-We examined the effects of 6 days of food restriction on salivary α-amylase (sAA), cortisol and dehydroepiandrostenedione (DHEA) awakening responses, psychological parameters and performance among 11 international weightlifters. Assessments were made at baseline (T1) and 6 days after a normal period of training while maintaining body weight (T2). Then, participants were assigned to 2 groups depending on whether they lost (Diet group) or maintained (Control group) their body mass. Anthropometric, psychological, physical, and physiological assessments were also realized 6 days (T3) after the restricted dietary period for the Diet group. Food restriction (T3) induced a significant rise of sAA awakening response (364.6%, p ≤ 0.05), whereas no significant variations were observed among the hypothalamic-pituitary-adrenal axis (cortisol and DHEA). Significant alterations of the general Recovery Score and General stress Score, evaluated through the Recovery-Stress Questionnaire for athletes, were noted after food restriction. Weightlifting performance, evaluated during a simulated weightlifting competition, was maintained after the 6-day food restriction; we even noted an increased weightlifting performance related to body mass (Sinclair coefficient). Our findings support the hypothesis that food restriction induces a challenging situation to the organism, resulting in an asymmetry between the 2 stress systems activation. These results reinforce the necessity to cautiously plan and monitor the weight regulation process before competition to avoid potential negative outcomes on psychophysiological parameters. In this regard, the psychobiological approach, especially the awakening responses, seems a useful tool.

Exercise and the Cortisol Awakening Response: A Systematic Review

Background

The cortisol awakening response (CAR) has been used as a biomarker of stress response in a multitude of psychological investigations. While a myriad of biochemical responses have been proposed to monitor responses to exercise training, the use of CAR within the exercise and sports sciences is currently limited and is a potentially underutilized variable. Therefore, the purpose of this review was to collate studies that incorporate both exercise and CAR, in an effort to better understand (a) whether CAR is a useful marker for monitoring exercise stress and (b) how CAR may be most appropriately used in future research.

Methods

A systematic review of the literature was conducted, following PRISMA guidelines. Searches were conducted using PubMed, SportDISCUS, Scopus, and PsychInfo databases, using search terms related toCAR and exercise and physical activity.

Results

10,292 articles were identified in the initial search, with 32 studies included in the final analysis. No studies investigated the effects of laboratory-controlled exercise on CAR. Variable effects were observed, possibly due to inconsistencies in study design, methodology, population, and CAR analysis. The available literature suggests a threshold of exercise may be required to alter the HPA axis and affect CAR. Moreover, CAR may represent a combination of previous exercise load and upcoming stress, making current interpretation of field-based observational research challenging.

Conclusions

More research is needed to fully elucidate the influence of exercise on CAR and address a number of gaps in the literature, including controlling exercise load, consistent sample collection, and CAR calculation and analysis.

Salivary alpha-amylase, salivary cortisol, and anxiety during a youth taekwondo championship: An observational study

The aim of this study was to assess the stress-related responses and the coach's capability to match perceived efforts of youth athletes during a taekwondo championship.Using a cross-sectional study design, salivary cortisol (sC) and alpha-amylase (sAA) were measured in 6 males and 3 females young (11.0 ± 0.9 years) athletes at awakening, 5 minutes before, and 1 minute and 30 minutes after official combats. State anxiety was recorded 60 minutes before the first competition, whereas coach's and athletes' ratings of perceived exertion (RPE) were obtained at the end of the combats. Time-matched (awakening and pre-competition) salivary samples and trait anxiety were collected 7-day postcompetition during a resting day.No effect for match outcome emerged. No difference emerged between athletes and coach RPEs. Higher (P = .03) state anxiety (41.6 ± 10.9 points) was shown than trait anxiety (34.8 ± 7.1 points). Time-matched sAA were similar. Peak sAA observed at the end of the combat (114.2 ± 108.1 U/mL) was higher (P < .01) than the other samples (range: 20.6-48.1 U/mL), whereas sC increased (P < .05) from awakening (8.0 ± 1.5 nmol/L), with peak levels observed at 30 minutes into the recovery phase (19.3 ± 4.3 nmol/L). Furthermore, pre-competition sC (16.5 ± 4.5 nmol/L) values were higher (P < .01) with respect to time-matched samples during the resting day (4.6 ± 1.0 nmol/L). The 3 athletes engaged in consecutive matches showed a tendency toward increasing sAA and sC.Taekwondo combats pose a high stress on young athletes, eliciting a fast reactivity of the sympathetic-adreno-medullary system relative to the hypothalamic-pituitary-adrenocortical system. Understanding the athlete's efforts during combats, coaches are recommended to apply effective recovery strategies between matches.

Changes of Swimmers' Emotional States during the Preparation of National Championship: Do Recovery-Stress States Matter?

This study examined the trajectories of emotional states and their within-person synergies with perceived stress and recovery during a 4-month training period preceding the French swimming championships. A Multilevel Growth Curve Analysis approach was used with 16 high level swimmers. Five waves of assessments of emotional states, perceived stress and recovery were completed. Results indicated that emotional states were characterized by distinct trajectories during the training period preceding a major competition. Specifically, significant positive linear effects of time (i.e., linear increase over time) and negative quadratic effects of squared time (i.e., inverted U shape over time) on anxiety, dejection and anger were observed, whereas the opposite pattern of results was found for happiness and excitement. Moreover, level 2 perceived stress and recovery (i.e., inter-individual predictors) were significantly associated with athletes' unpleasant and pleasant emotional states respectively. At level 1, perceived recovery (i.e., intra-individual predictor) was positively associated with happiness and excitement and negatively related to anxiety, dejection and anger. Finally, within-person interactions of general stress and recovery with time and squared time reached significance for excitement, whereas within-person interactions of specific and total stress with time and squared time reached significance for anxiety. Overall, this study provided insights into the central role played by perceived stress and recovery on the emotional states experienced by high level swimmers. Operational strategies were suggested in order to optimize the stress-recovery balance and in turn the athletes' emotional states during a complete training program.

Food restriction alters salivary cortisol and α-amylase responses to a simulated weightlifting competition without significant performance modification

The aim of this investigation was to evaluate the effect of a 6-day food restriction period on the physiological responses and performance of 11 high-level weightlifters. After a period of weight maintenance (T₂), they were assigned into two groups depending on whether they lost (Diet group, n = 6) or maintained their body weight (Control group, n = 5) during the course of those 6 days. An evaluation of performance and the measurement of salivary cortisol concentrations and salivary α-amylase (sAA) activity were performed during a simulated weightlifting competition which took place at T₂, after a 6-day period of food restriction (T₃). Dietary data were collected using a 6-day diet record. We noted a 41.8% decrease in mean energy intake during the dietary restriction period, leading to a 4.34% weight loss for the Diet group. Dietary restriction did not modify absolute performance levels, whilst a significant improvement was noted for the Control group. Furthermore, we noted a response of decreased salivary cortisol and increased sAA activity to the simulated competition stress at T₃ for the Diet group. These results may indicate that dietary reduction led to a dissociation of the hypothalamo-pituitary-adrenal axis and the sympatho-adreno-medullary system, which could impair training adaptations and absolute performance development.

Physical activity buffers fatigue only under low chronic stress

Fatigue is one of the most commonly reported complaints in the general population. As physical activity (PA) has been shown to have beneficial effects, we hypothesized that everyday life PA improves fatigue. Thirty-three healthy students (21 women, 22.8 ± 3.3 years, 21.7 ± 2.3 kg/m(2)) completed two ambulatory assessment periods. During five days at the beginning of the semester (control condition) and five days during final examination preparation (examination condition), participants repeatedly reported on general fatigue (awakening, 10 am, 2 pm, 6 pm and 9 pm) by means of an electronic diary, collected saliva samples for the assessment of cortisol and α-amylase immediately after providing information on fatigue and wore a triaxial accelerometer to continuously record PA. Self-perceived chronic stress was assessed as a moderator. Using hierarchical linear modeling, including PA, condition (control vs. examination), sex and chronic stress as predictors, PA level during the 15 min prior to data entry did not predict momentary fatigue level. Furthermore, there was no effect of condition. However, a significant cross-level interaction of perceived chronic stress with PA was observed. In fact, the (negative) relationship between PA and fatigue was stronger in those participants with less chronic stress. Neither cortisol nor α-amylase was significantly related to physical activity or fatigue. Our study showed an immediate short-term buffering effect of everyday life PA on general fatigue, but only when experiencing lower chronic stress. There seems to be no short-term benefit of PA in the face of higher chronic stress. These findings highlight the importance of considering chronic stress when evaluating the effectiveness of PA interventions in different target populations, in particular among chronically stressed and fatigued subjects.

Salivary Hormones Response to Preparation and Pre-competitive Training of World-class Level Athletes

This study aimed to compare the response of salivary hormones of track and field athletes induced by preparation and pre-competitive training periods in an attempt to comment on the physiological effects consistent with the responses of each of the proteins measured. Salivary testosterone, cortisol, alpha-amylase, immunoglobulin A (IgA), chromogranin A, blood creatine kinase activity, and profile of mood state were assessed at rest in 24 world-class level athletes during preparation (3 times in 3 months) and pre-competitive (5 times in 5 weeks) training periods. Total mood disturbance and fatigue perception were reduced, while IgA (+61%) and creatine kinase activity (+43%) increased, and chromogranin A decreased (-27%) during pre-competitive compared to preparation period. A significant increase in salivary testosterone (+9 to +15%) and a decrease in testosterone/cortisol ratio were associated with a progressive reduction in training load during pre-competitive period (P < 0.05). None of the psycho-physiological parameters were significantly correlated to training load during the pre-competitive period. Results showed a lower adrenocortical response and autonomic activity, and an improvement of immunity status, in response to the reduction in training load and fatigue, without significant correlations of salivary hormones with training load. Our findings suggest that saliva composition is sensitive to training contents (season period) but could not be related to workload resulting from track and field athletics training.

Entwicklung der Kurzskala zur Erfassung von Erholung und Beanspruchung im Sport (KEB)

Zusammenfassung. Mit der Entwicklung einer Kurzform (Kurzskala zur Erfassung von Erholung und Beanspruchung im Sport; KEB) des Akutmaßes zur Erfassung von Erholung und Beanspruchung im Sport (AEB) wird dem Bedarf der Sportpraxis nach einem ökonomischen, validen und veränderungssensitiven Messinstrument zur Erfassung von Erholung und Beanspruchung nachgegangen. Nach einem vierstufigen Entwicklungs- und Validierungsprozess des AEB wurde aus den exploratorisch errechneten und konfirmatorisch geprüften Faktoren des AEB die KEB mit acht Items abgeleitet. Es konnten sehr gute Bereichshomogenitäten, moderate Interkorrelationen und hypothesenkonforme Korrelationen mit dem AEB berechnet werden. Der KEB zeigte ein dem AEB inhaltlich übereinstimmendes Korrelationsmuster mit den konvergenten Verfahren Erholungs-Belastungs-Fragebogen für Sportler (EBF-Sport) und visuelle Analogskala zum Muskelschmerzempfinden (Delayed-onset muscle soreness; DOMS). In einem Trainingsmonitoring mit der deutschen Hockey-Juniorinnen-Nationalmannschaft wurde die Veränderungssensitivität der KEB belegt und ein übereinstimmendes Ergebnismuster mit dem AEB, dem EBF-Sport und der DOMS gefunden.

Monitoring the athlete training response: subjective self-reported measures trump commonly used objective measures: a systematic review

Background

Monitoring athlete well-being is essential to guide training and to detect any progression towards negative health outcomes and associated poor performance. Objective (performance, physiological, biochemical) and subjective measures are all options for athlete monitoring.

Objective

We systematically reviewed objective and subjective measures of athlete well-being. Objective measures, including those taken at rest (eg, blood markers, heart rate) and during exercise (eg, oxygen consumption, heart rate response), were compared against subjective measures (eg, mood, perceived stress). All measures were also evaluated for their response to acute and chronic training load.

Methods

The databases Academic search complete, MEDLINE, PsycINFO, SPORTDiscus and PubMed were searched in May 2014. Fifty-six original studies reported concurrent subjective and objective measures of athlete well-being. The quality and strength of findings of each study were evaluated to determine overall levels of evidence.

Results

Subjective and objective measures of athlete well-being generally did not correlate. Subjective measures reflected acute and chronic training loads with superior sensitivity and consistency than objective measures. Subjective well-being was typically impaired with an acute increase in training load, and also with chronic training, while an acute decrease in training load improved subjective well-being.

Summary

This review provides further support for practitioners to use subjective measures to monitor changes in athlete well-being in response to training. Subjective measures may stand alone, or be incorporated into a mixed methods approach to athlete monitoring, as is current practice in many sport settings.

Markers of biological stress and mucosal immunity during a week leading to competition in adolescent swimmers

In this study we examined changes in the salivary concentrations of immunoglobulin A (sIgA), cortisol (sC), testosterone (sT), and testosterone-to-cortisol ratio (T/C) in 21 competitive swimmers, 11–15 years old, during a week leading to competition as compared to a control (noncompetition) week. No day-to-day changes or significant differences between weeks were observed for sIgA (47.9 ± 4.4 versus 54.9 ± 5.2 μg/mL for control versus competition week, resp.), sC (2.7 ± 0.2 versus 2.5 ± 0.2 ng/mL for control versus competition week, resp.), and T/C ratio (83.4 ± 7.0 versus 77.9 ± 7.7 for control versus competition week, resp.). In contrast, sT was significantly lower during the week of competition (154.5 ± 11.3 pg/mL) as compared to the control week (181.3 ± 11.5 pg/mL) suggesting that the swimmers were in a catabolic state, although this did not have a negative effect on their performance. In conclusion, salivary cortisol did not change between the two weeks, and thus competition stress was relatively low, and mucosal immunity was unaffected in these young athletes prior to competition.

Changes in mood states and salivary cortisol levels following two months of training in elite female water polo players

Psychological and physiological markers have been used to maximize competitive sport preparation. The aim of the present study was to evaluate the effects of two months of training and competitions on mood states and salivary cortisol diurnal variation in 15 female elite water polo players. The results demonstrated that the β coefficient values of the regression slope of cortisol values on sampling time was significantly flatter following the training period. The values of the area under the cortisol curve (AUC) 'with respect to ground' (AUCg) and those of the β coefficients of the slope of the diurnal change in cortisol levels were highly negatively correlated. The slope correlated positively with the dysfunctional Profile of Mood States scale and negatively with the functional scale. AUCg correlated negatively with dysfunctional factors and positively with the vigor index. These findings support the hypothesis that subclinical hypocortisolism and a flattened diurnal rhythm of cortisol may play a role in determining dysfunctional mood states.