Cognitive depressive symptoms associated with delayed heart rate recovery following interpersonal stress in healthy men and women

Among cardiac patients, research suggests that somatic depressive symptoms are more strongly associated with altered cardiovascular responses to stress than cognitive depressive symptoms. This study sought to determine whether this was also the case in healthy individuals. One hundred and ninety-nine adults from the community completed the Beck Depression Inventory II (BDI-II) and underwent psychological laboratory stressors while their blood pressure, heart rate, and heart rate variability were monitored. A cognitive-affective factor and somatic-affective factor were identified within the BDI-II, but only the cognitive factor was associated with reduced heart rate recovery following the stressors in multivariate analyses examining both factors simultaneously. This suggests that cognitive depressive symptoms may be more strongly related to altered stress physiology following psychological stressors.     

Differential exposure and reactivity to interpersonal stress predict sex differences in adolescent depression.

This study tested the hypothesis that higher rates of depression in adolescent girls are explained by their greater exposure and reactivity to stress in the interpersonal domain in a large sample of 15-year-olds. Findings indicate that adolescent girls experienced higher levels of total and interpersonal episodic stress, whereas boys experienced higher levels of chronic stress (academic and close friendship domains). Higher rates of depression in girls were explained by their greater exposure to total stress, particularly interpersonal episodic stress. Adolescent girls were also more reactive (more likely to become depressed) to both total and interpersonal episodic stress. The findings suggest that girls experience higher levels of episodic stress and are more reactive to these stressors, increasing their likelihood of becoming depressed compared to boys. Results were discussed in terms of girls' greater interpersonal focus and implications for understanding sex differences in depression.     

Hostility and cardiovascular reactivity to stress in women and men

The relationship of Cook Medley hostility scores (Ho) to blood pressure and heart rate reactivity was examined in 56 women and 56 men. Stress was elicited by an unsolvable anagram task that was described as easily solvable. Both men and women scoring high on Ho had greater blood pressure responses to the task. Those scoring high on Ho also reported more anger in response to the tasks, but anger was not associated with blood pressure reactivity. It was concluded that situations evoking suspiciousness and mistrust rather than anger may be necessary to elicit increased blood pressure reactivity among high Ho subjects.     

Cortisol levels predict motion sickness tolerance in women but not in men

A variety of intrinsic and extrinsic factors contribute to motion sickness severity in a stressful motion environment. The interplay of all these factors may partially explain the high inter-subject variability of motion sickness susceptibility found in many studies as well as some of the contradictory findings between studies regarding the modulating influence of single factors. We investigated the role of endogenous cortisol levels, gender and repetitive experience for motion sickness susceptibility. Motion sickness was induced in 32 healthy, but motion-sickness susceptible volunteers (16:16 males:females), by means of a vection drum. Subjects were investigated between 8:00 am (high cortisol) and 11:00 am (low cortisol), and on five consecutive days. Tolerance to rotation (RT) of the drum, motion sickness symptom ratings (SR) and salivary cortisol levels were assessed. Baseline cortisol levels correlated positively with RT in women, but not in men. RT showed a gender-specific time course across days, with higher values in males than in females on day 1, and sensitization on day 3 only in men. SR and cortisol levels following rotation did not differ between males and females, or between testing days. Gender differences in motion sickness susceptibility appear to be linked to a different role of basal cortisol levels for motion sickness tolerance. Results clearly indicate the need to control for gender, day time and cortisol levels in studies of motion sickness.     

Acute exercise improves endothelial function despite increasing vascular resistance during stress in smokers and nonsmokers

The present study examined the effect of acute exercise on flow mediated dilation (FMD) and reactivity to neurovascular challenges among female smokers and nonsmokers. FMD was determined by arterial diameter, velocity, and blood flow measured by Doppler ultrasonography after forearm occlusion. Those measures and blood pressure and heart rate were also assessed in response to forehead cold and the Stroop Color‐Word Conflict Test (CWT) before and after 30 min of rest or an acute bout of cycling exercise (～50% VO₂peak). Baseline FMD and stress responses were not different between smokers and nonsmokers. Compared to passive rest, exercise increased FMD and decreased arterial velocity and blood flow responses during the Stroop CWT and forehead cold in both groups. Overall, acute exercise improved endothelial function among smokers and nonsmokers despite increasing vascular resistance and reducing limb blood flow during neurovascular stress.     

Differences in the attitudes of men and women practitioners to responsibility and competence.

A study has been carried out to predict the prescribing and referral behaviour of general practitioners by measuring their attitudes to their roles. Part of this study involved determining whether women doctors accept greater responsibility and feel more competent than men when undertaking those tasks for which they are said to be suited. In May 1987 a postal questionnaire was sent to all 525 general practitioners in contract with Avon family practitioner committee. Replies from 82 women and 289 men showed that women accepted more responsibility for sex-related tasks. For other medical tasks, including those of a technical and traditional nature, men accepted both more responsibility and felt more competent than did women respondents. Contrary to expectations, women did not accept more responsibility or feel more competent than men for psychosocial tasks. The results are discussed in the context of the role of women within medicine.     

Respiratory mechanics during exercise in endurance-trained men and women

The purpose of this study was to compare the mechanics of breathing including the measurement of expiratory flow limitation, end-expiratory lung volume, end-inspiratory lung volume, and the work of breathing in endurance-trained men ( n = 8) and women ( n = 10) during cycle exercise. Expiratory flow limitation was assessed by applying a negative expiratory pressure at the mouth. End-expiratory lung volume and end-inspiratory lung volume were determined by having subjects perform inspiratory capacity manoeuvres. Transpulmonary pressure, taken as the difference between oesophageal and airway opening pressure, was plotted against volume and integrated to determine the work of breathing. Expiratory flow limitation occurred in nine females (90%) and three males (43%) during the final stage of exercise. Females had a higher relative end-expiratory lung volume (42 ± 8 versus 35 ± 5% forced vital capacity (FVC)) and end-inspiratory lung volume (88 ± 5 versus 82 ± 7% FVC) compared to males at maximal exercise ( P < 0.05). Women also had a higher work of breathing compared to men across a range of ventilations. On average, women had a work of breathing that was twice that of men at ventilations above 90 l min⁻¹. These data suggest that expiratory flow limitation may be more common in females and that they experience greater relative increases in end-expiratory lung volume and end-inspiratory lung volume at maximal exercise compared to males. The higher work of breathing in women is probably attributed to their smaller lung volumes and smaller diameter airways. Collectively, these findings suggest that women utilize a greater majority of their ventilatory reserve compared to men and this is associated with a higher cost of breathing.     

Ethics and Society: Current attitudes towards egg donation among men and women

Recent widespread concern has led to legislation in the UK preventingthe use of fetal ovarian tissue for the treatment of infertilewomen. This questionnaire-based study aimed to assess the attitudesof both fertile and infertile men and women as well as egg donorsand recipients towards the use of donated eggs for treatment,diagnosis and research. Fertile individuals were significantlyless aware of egg donation but the majority in both the fertileand the infertile groups approved the use of eggs for research(89 and 95% of women and 88 and 92% of men respectively) andtreatment (similar percentages). However, fetal sources of oocyteswere acceptable to only 15% of women in the fertile, 21% inthe infertile, 35% in the recipient and 19% in the donor groups.Cadaveric sources of oocytes were slightly more acceptable (28%fertile, 28% infertile, 50% recipient and 42% donors). Boththese sources of oocytes were slightly more acceptable to men.Education had little influence on attitudes, although men andwomen of tertiary education level said they would be less likelyto have gamete donation themselves. Thus there would appearto be widespread approval for the use of donor eggs in researchand treatment but not if the source of eggs is fetal or cadaveric.     

Dynamics of sweating in men and women during passive heating

Summary The dynamics of sweating was investigated at rest in 8 men and 8 women. Electrical skin resistance (ESR), rectal temperature (T_re) and mean skin temperature were measured in subjects exposed to 40‡ C environmental temperature, 30% relative air humidity, and 1 m · s⁻¹ air flow. Sweat rate was computed from continuous measurement of the whole body weight loss. It was found that increases in T_re, and mean body temperature were higher in women than in men by 0.16, 0.38 and 0.21‡ C, but only the difference in δ was significant (p<0.05). The dynamics of sweating in men and women respectively, was as follows: delay (t_d) 7.8 and 18.1 min (p<0.01), time constant (Τ) 7.5 and 8.8 min (N.S.), inertia time (t_i) 15.3 and 26.9 min (p<0.002), and total body weight loss 153 and 111 g · m⁻² · h⁻¹ (p<0.001). Dynamic parameters of ESR did not differ significantly between men and women. Inertia times of ESR and sweat rate correlated in men (r=0.93, p<0.001), and in women (r=0.76, p<0.02). In men, δ T_re correlated with inertia time of sweat rate (r=0.81, p<0.01) as well as with the inertia time of ESR (r=0.83, p<0.001). No relation was found between δ T_re and the dynamics of sweating in women. It is concluded that the dynamics of sweating plays a decisive role in limiting δ T_re in men under dry heat exposure. The later onset of sweating in women does not influence the rectal temperature increase significantly. In women, δ T_re is probably limited by a complex interaction of sweating, skin blood flow increase, and metabolic rate decrease. This work was supported by the Centre National de la Recherche Scientifique and Polish Academy of Siences     

Plasma catecholamine responses to four resistance exercise tests in men and women

The plasma adrenaline ([A]) and noradrenaline ([NA]) concentration responses of nine men and eight women were investigated in four resistance exercise tests (E80, E60, E40 and E20), in which the subjects had to perform a maximal number of bilateral knee extension-flexion movements at a given cycle pace of 0.5?Hz, but at different load levels (80%, 60%, 40% and 20% of 1 repetition maximum, respectively). The four test sessions were separated by a minimal interval of 3 rest days. The number of repetitions (Rep_max), the total work (W _tot) done normalized for the lean body mass and the heart rate (HR) responses were similar in the two groups in each test. In addition, no differences were found between the two groups in [A] and [NA] either before or after the exercise tests. The postexercise [NA], both in the men [10.8 (SD 7.0) nmol?·?l^?1] and in the women [11.7 (SD 7.4) nmol?·?l^?1], was clearly the highest in E20, where also the Rep_max, W _tot, the total amount of integrated electromyograph activity in the agonist muscles and the peak postexercise blood lactate concentration [men 8.3 (SD 1.6) vs women 7.3 (SD 0.9) mmol?·?l^?1, ns] were significantly higher than in the other tests. Although the postexercise [A] in E20 both in the men [7.1 (SD 6.0) nmol?·?l^?1] and in the women [5.2 (SD 2.0) nmol?·?l^?1] were higher than in E80 [men 3.1 (SD 4.2), women 2.1 (SD 2.0) nmol?·?l^?1] (P??1] and E40 [men 3.8 (SD 4.1), women 5.8 (SD 4.0) nmol?·?l^?1] in either group. The present study did not indicate any sex differences in performance and in plasma catecholamine responses in different exhausting resistance exercise tests performed with the knee extensor muscles. In both groups the plasma [NA] response was clearly the largest in the longest exercise with the greatest amount of muscle activity and work done, and with the largest blood lactate response. The differences in the plasma [A] responses between the exercises tended to be somewhat smaller.     

Peripheral vascular response to local cold stress of tropical men during sojourn in the Arctic cold region.

Peripheral vascular response to local cold stress was studied on 4 groups of volunteers by eliciting cold-induced vasodilatation (CIVD) response during immersion of right hand in cold water (4 degrees C) for 30 min, to examine whether tropical men can get acclimatized to local cold compared to temperate zone people, during Arctic cold exposure. Group A and B (10 each) were drawn from tropical region of India, while Group C and D (6 each) from temperate zone of Russia and natives of Arctic, respectively. Initial study was conducted on control Group A at Delhi. Group B was airlifted to the Arctic (70 degrees N, 38 degrees E), where measurements were done on them during the seventh week of acclimatization, then they were flown back to Delhi and retested. For comparison, study was done at the Arctic on six migrants (Group C) from temperate zone of Russia and 6 natives (Group D) of the Arctic. There was a significant improvement of CIVD response and peripheral blood flow of tropical men due to acclimatization to Arctic environment, which was similar to that of the migrants but lower than the natives. Thus local cold acclimatization is possible even in tropical men as in those of the temperate zone people.     

DHEA and DHEA-S response to acute psychosocial stress in healthy men and women

This study investigates the effect of acute psychosocial stress on serum concentrations of DHEA and DHEA-S in healthy men and women. Twenty men and 19 women (age 30-50 years) underwent Trier Social Stress Test (TSST). Physiological measurements were performed before, directly after the stress test and after 30 mins of recovery. In both men and women, significantly elevated DHEA and DHEA-S levels were observed in response to the stressor. There was a large inter-individual variation in the magnitude of the response, especially for DHEA but no statistical difference between men and women. Magnitude of the change in the levels of DHEA was found to be positively associated with the magnitude of the changes in ACTH, cortisol and heart rate. Furthermore, the results of this study suggest that the capacity to secrete DHEA and DHEA-S during acute psychosocial stress declines with age.     

Muscle damage responses and adaptations to eccentric-overload resistance exercise in men and women

Purpose

This study assessed markers of muscle damage and training adaptations to eccentric-overload flywheel resistance exercise (RE) in men and women.

Methods

Dynamic strength (1 RM), jump performance, maximal power at different percentages of 1 RM, and muscle mass in three different portions of the thigh were assessed in 16 men and 16 women before and after 6 weeks (15 sessions) of flywheel supine squat RE training. Plasma creatine kinase (CK) and lactate dehydrogenase (LDH) concentrations were measured before, 24, 48 and 72 h after the first and the last training session.

Results

After training, increases in 1 RM were somewhat greater (interaction P < 0.001) in men (25 %) than in women (20 %). Squat and drop jump height and power performance at 50, 60, 70 and 80 % of 1 RM increased after training in both sexes (P < 0.05). Power improvement at 80 % of 1 RM was greater (interaction P < 0.02) in men than women. Muscle mass increased ~5 % in both groups (P < 0.05). CK increased in men after the first training session (P < 0.001), whereas the response in women was unaltered. In both sexes, LDH concentration was greater after the first training session compared with basal values (P < 0.05). After the last session, CK and LDH remained at baseline in both groups.

Conclusions

These results suggest that although improvements in maximal strength and power at high loads may be slightly greater for men, eccentric-overload RE training induces comparable and favorable gains in strength, power, and muscle mass in both men and women. Equally important, it appears muscle damage does not interfere with the adaptations triggered by this training paradigm.     

Work stress precipitates depression and anxiety in young, working women and men

BACKGROUND: Rates of depression have been rising, as have rates of work stress. We tested the influence of work stress on diagnosed depression and anxiety in young working adults. METHOD: Participants were enrolled in the Dunedin study, a 1972-1973 longitudinal birth cohort assessed most recently in 2004-2005, at age 32 (n=972, 96% of 1015 cohort members still alive). Work stress (psychological job demands, work decision latitude, low work social support, physical work demands) was ascertained by interview. Major depressive disorder (MDD) and generalized anxiety disorder (GAD) were ascertained using the Diagnostic Interview Schedule (DIS) and diagnosed according to DSM-IV criteria. RESULTS: Participants exposed to high psychological job demands (excessive workload, extreme time pressures) had a twofold risk of MDD or GAD compared to those with low job demands. Relative risks (RRs) adjusting for all work characteristics were: 1.90 [95% confidence interval (CI) 1.22-2.98] in women, and 2.00 (95% CI 1.13-3.56) in men. Analyses ruled out the possibility that the association between work stress and disorder resulted from study members' socio-economic position, a personality tendency to report negatively, or a history of psychiatric disorder prior to labour-market entry. Prospective longitudinal analyses showed that high-demand jobs were associated with the onset of new depression and anxiety disorder in individuals without any pre-job history of diagnosis or treatment for either disorder. CONCLUSIONS: Work stress appears to precipitate diagnosable depression and anxiety in previously healthy young workers. Helping workers cope with work stress or reducing work stress levels could prevent the occurrence of clinically significant depression and anxiety.     

Respiratory kinematics by optoelectronic plethysmography during exercise in men and women

Gender differences in resting pulmonary function are attributable to the smaller lung volumes in women relative to men. We sought to investigate whether the pattern of response in operational lung volumes during exercise is different between men and women of similar fitness levels. Breath-by-breath volume changes of the entire chest wall ( _CW) and its rib cage ( _Rc) and abdominal ( _Ab) compartments were studied by optoelectronic plethysmography in 15 healthy subjects (10 men) who underwent a symptom-limited ( W _peak) incremental bicycle test. The pattern of change in end-inspiratory and end-expiratory _CW ( _CW,EI and _CW,EE, respectively) did not differ between the sexes. With increasing workload the decrease in _CW,EE was almost entirely attributable to a reduction in end-expiratory _Ab, whereas the increase in _CW,EI was due to the increase in end-inspiratory _Rc in both sexes. In men, at W _peak tidal volume [ _T, 2.7 (0.2) l] and inspiratory capacity [IC, 3.4 (0.2) l] were significantly greater than in women [1.8 (0.2) and 2.6 (0.2) l, respectively]. However, after controlling for lung size using forced vital capacity (FVC) as a surrogate, the differences between men and women were eliminated [ _T /FVC 49 (3) and 45 (3) respectively, and IC/FVC 63 (2) and 65 (3) respectively]. All data are presented as mean (SE). In both men and women the contribution of the rib cage compartment to _T expansion was significantly greater than that of the abdominal compartment. We conclude that gender differences in operational lung volumes in response to progressive exercise are principally attributable to differences related to lung size, whereas compartmental chest wall kinematics do not differ among sexes.     

Plasma volume during heat stress and exercise in women

Summary Five women were studied during exercise and passive heating to determine whether PV dynamics were affected by the menstrual cycle. The exercise bout (80% peak) on a modified cycle ergometer and the passive heat stress were done in a hot environment (T_a=50°C, P_w=1.61kPa) during the follicular and luteal phase. Esophageal temperature (T_es) was measured continuously. Blood samples were drawn after each 0.2° C increase in T_es and was measured at that time. Initial PV was estimated at rest during the follicular phase. PV changes from rest were calculated at each T_es from Hb and Hct. During passive heating, PV decreased by a mean volume of 156 (±80) ml to 2.83 (±0.09)l in the follicular phase. During the luteal phase, there was a larger volume reduction (300±100 ml) during passive heating, and the final PV was lower than in the follicular phase and averaged 2.47±0.181. During exercise, PV decreased 463 (±90) ml to 2.50 (±0.11) l in the follicular and 381 (±70) ml to 2.50 (±0.23) l in the luteal phase. These data indicate that there is a menstrual cycle effect on PV dynamics during passive heating such that more fluid is shifted out of the vasculature during the luteal phase. During severe exercise there is a greater fluid loss during the follicular phase, yet the final PV is not different between phases.