Women's intercollegiate athletic competition: Cortisol,testosterone, and the dual-hormone hypothesis as it relates to status among teammates

Recent research suggests that testosterone and cortisol jointly regulate dominance motivation and, perhaps, the status relationships that are affected by it. For this article, the results of six different studies of women's intercollegiate athletic competition were combined to give a sample size of almost ninety women for whom we had before- and after-competition values for salivary cortisol and testosterone for at least one and sometimes two competitions. For many of these women, we had surveys that allowed us to assess their status with teammates. In no matter what sport (soccer, softball, volleyball, and tennis) levels of salivary cortisol and testosterone increased when women participated in athletic competition. Salivary levels of C and T appear to rise in parallel during competition and increases in levels of one hormone are significantly related to increases in the other. Salivary levels of these hormones typically decreased for teammates who did not play but watched the competition from the sidelines. For women who played in two competitions, individual differences in the positive effect of competition on cortisol and testosterone were conserved from one competition to the next, affirming the personal consistency of endocrine responses to competition. Status with teammates was positively related to before-competition levels of testosterone, but only for women with relatively low before-competition levels of cortisol. This result provides novel support for the “dual-hormone hypothesis” as it relates to predicting social status in women's athletic teams — natural social groups of individuals who know each other and whose social hierarchy has evolved over the course of practice and play for at least one and, in some cases, several years of intercollegiate athletic competition.     

Interspecies hormonal interactions between man and the domestic dog (Canis familiaris)

To date, hormonal influence in interspecies interaction has not been examined. In a study of a dog agility competition among human/dog teams, men's pre-competition basal testosterone (T) levels were positively related to changes in dogs' cortisol levels from pre- to post-competition, but only among losing teams. Furthermore, pre-competition basal T in men on losing teams predicted more than half of the variance in dogs' cortisol change. This relationship was mediated through men's punitive and affiliative behaviors towards their dogs immediately after competition. Men's T change was also a significant predictor of dogs' change in cortisol such that men who experienced greater decreases in T after a loss were associated with dogs that experienced greater increases in cortisol. In winning teams, men's pre-competition T and T changes were unrelated to dogs' cortisol changes. These results are discussed in light of T as a proxy for dominance motivation as well as T's relation to stress across the species boundary.     

A meta-analytic review of the association between cortisol reactivity in response to a stressor and attention-deficit hyperactivity disorder

A substantial literature suggests that abnormal cortisol reactivity may be a vulnerability for deleterious mental health outcomes, including ADHD. ADHD has been linked with difficulty in emotion regulation and increased risk of experiencing stressors, both of which may be related to psychobiological abnormalities (e.g., abnormal cortisol reactivity). Research has been mixed regarding the association between cortisol reactivity and ADHD. Therefore, the present meta-analytic review (k = 12) sought to quantify this association and review the relevant methodological issues and theoretical implications of this area of research. Overall, no effect was found between cortisol reactivity and ADHD (r = 0), although significant heterogeneity in the analyses suggested that there might be moderators of this association, if one does exist. Results highlight the importance of addressing limitations of the current literature on cortisol reactivity and ADHD and exploring additional indices of emotion regulation that may be associated with ADHD. Implications for future research efforts are discussed.     

Hormonal response to competition among male coalitions

Previous research has shown that testosterone (T) and cortisol (C) are released in response to a wide variety of social stimuli including dyadic (one on one) competitive events, but humans also compete as groups. Here we report results from a pilot study of hormonal responses to competition between male coalitions. Salivary T and C levels were assessed in adult males from a rural Caribbean village who competed at dominoes, as two-man teams, against (a) familiar men from their own village (within coalition), and (b) strangers from another village (between coalitions). Analyses indicate that both T and C levels were higher and responses more pronounced for between-village competition than for within-village competition, but we could not compare responses to victory and defeat in the between-village case, since our subjects happened to win both such contests. Further studies of endocrine responses in the context of coalitional competition are warranted.     

Cortisol Predicts Performance During Competition: Preliminary Results of a Field Study with Elite Adolescent Taekwondo Athletes

Competitive taekwondo composes a high stress situation leading to an increase in the stress hormone cortisol. Little is known about cortisol’s relation to outcome (winning vs. losing) and performance in taekwondo. Therefore, the aim of the study was to investigate cortisol relation to outcome, performance and whether cortisol can predict performance during a competition. Twenty taekwondo combatants (13 males; M_age = 15) provided four salivary samples (C1: 30 min prior, C2: during, C3: after, and C4: 30 min after competition) during an international competition. Total points made in the two rounds during their first fight were used as a performance indicator. Results show no difference in cortisol between winners and losers, before or after competition. However, a negative correlation between performance and C1 as well as C4 was detected. Unexpected, a positive correlation between cortisol during the competition (C2) and performance was identified. A stepwise multiple regression analyses showed that C2 predicted 25.5% of the performance variance. Even if the sample size is relatively small due to the field experimental setting, some conclusions can be drawn to motivate future research. Potentially, in taekwondo it seems advantageous for performance to have higher levels of stress as indicated by cortisol during a competition, whereas particularly before the competition, sport psychological interventions should be provided to combatants to reduce their psychophysiological stress level.     

Comparison of clear and narrow outcomes on testosterone levels in social competition

A contribution to a special issue on Hormones and Human Competition.Social competition is associated with marked emotional, behavioral and hormonal responses, including changes in testosterone levels. The strength and direction of these responses is often modulated by levels of other hormones (e.g. cortisol) and depends on psychological factors – classically, the objective outcome of a competition (win vs. loss) but also, hypothetically, the closeness of that outcome (e.g. decisive victory vs. close victory). We manipulated these two aspects of a social contest among male participants (N = 166), to investigate how testosterone and affect fluctuated as a function of clear vs. narrow wins and clear vs. narrow losses. We found that losing a competition by a small margin (a narrow loss) was experienced as more pleasant than a clear loss. Among individuals with higher levels of basal cortisol, winning the competition by a narrow margin was associated with a decrease in testosterone levels. These findings are discussed within the framework of the status instability hypothesis and the growing literature on how situational and physiological factors modulate testosterone reactivity to social contests.     

Effects of affiliation and power motivation arousal on salivary progesterone and testosterone

Following up on earlier research suggesting a link between implicit affiliation motivation and progesterone (P) and implicit power motivation and testosterone [T; Schultheiss, O.C., Dargel, A., Rohde, W., 2003. Implicit motives and gonadal steroid hormones: Effects of menstrual cycle phase, oral contraceptive use, and relationship status. Horm. Behav. 43, 293-301.], we tested whether arousal of affiliation motivation increases P levels and whether arousal of power motivation increases T levels. Sixty subjects were randomly assigned to watch 30 min of either Bridges of Madison County (affiliation arousal) or The Godfather II (power arousal), or a documentary about the Amazon (control condition). Levels of P and T were assessed in saliva samples taken before (T1), immediately after (T2), and 45 min after the movie (T3). The efficacy of experimental conditions to differentially arouse motives was verified by assessment of changes in affiliation and power motive imagery expressed in imaginative stories written before and after the movie. After the movie, salivary P levels (T2 and T3) in the affiliation-arousal group were significantly higher than in the control group and marginally higher than in the power-arousal group. Subjects' postmovie T responses (T3) depended on premovie T levels: in men, higher premovie T levels predicted a greater likelihood of postmovie T increases in the Power Arousal condition but not in the other conditions, whereas in women, higher premovie T levels tended to be associated with postmovie T decreases in the Power Arousal condition but not in the other conditions. These findings suggest that aroused affiliation motivation has a specific stimulatory effect on P, whereas aroused power motivation has a specific stimulatory effect on T in men, but not in women, with high baseline T levels.     

The effects of competition and implicit power motive on men's testosterone,emotion recognition,and aggression

A contribution to a special issue on Hormones and Human Competition.We investigated the effects of competition on men's testosterone levels and assessed whether androgen reactivity was associated with subsequent emotion recognition and reactive and proactive aggression. We also explored whether personalized power (p Power) moderated these relationships. In Study 1, 84 males competed on a number tracing task and interpreted emotions from facial expressions. In Study 2, 72 males competed on the same task and were assessed on proactive and reactive aggression. In both studies, contrary to the biosocial model of status (Mazur, 1985), winners' testosterone levels decreased significantly while losers' levels increased, albeit not significantly. Personalized power moderated the effect of competition outcome on testosterone change in both studies. Using the aggregate sample, we found that the effect of decreased testosterone levels among winners (compared to losers) was significant for individuals low in p Power but not for those with medium or high p Power. Testosterone change was positively related to emotion recognition, but unrelated to either aggression subtype. The testosterone-mediated relationship between winning and losing and emotion recognition was moderated by p Power. In addition, p Power moderated the direct (i.e., non-testosterone mediated) path between competition outcome and emotion recognition and both types of aggression: high p-Power winners were more accurate at deciphering others' emotions than high p-Power losers. Finally, among high p-Power men, winners aggressed more proactively than losers, whereas losers aggressed more reactively than winners. Collectively, these studies highlight the importance of implicit power motivation in modulating hormonal, cognitive, and behavioral outcomes arising from human competition.     

Do Nematode Infections of Red Colobus (Procolobus rufomitratus) and Black-and-White Colobus (Colobus guereza) on Humanized Forest Edges Differ from Those on Nonhumanized Forest Edges?

Forested edges, especially those that border humanized landscapes, provide opportunities for nonhuman primates and people to interact, and such interactions are predicted to alter disease dynamics. Given the rapid expansion of edge habitats globally, understanding changes occurring on edges is important in evaluating primate behavioral ecology and developing conservation plans. Our research investigates predictions concerning how gastrointestinal parasite and stress levels (cortisol) in red colobus and black-and-white colobus (Procolobus rufomitratus; Colobus guereza) in Kibale National Park, Uganda, differ between humanized and nonhumanized forest edges. We found Trichuris sp., an unidentified strongyle, and Strongyloides sp. in the fecal samples. Results did not generally support our expectation that humanized forest edges increase parasite infection and, counter to what we predicted, fecal cortisol did not differ between habitats, suggesting that proximity to edges and/or to humans did not result in increased stress. We conclude that broad habitat classifications, e.g., “humanized,” may be too general to identify consistent differences in parasite infection, as other factors, specific to the parasite (e.g., life cycled), host (e.g., immune systems strength), or environment (e.g., moisture level), likely also play important roles.     

Physiological and Behavioral Effects of Capture Darting on Red Colobus Monkeys (Procolobus rufomitratus) with a Comparison to Chimpanzee (Pan troglodytes) Predation

Understanding how human activities affect wild primates is critical to the design of effective conservation strategies. Despite this need, few studies have examined the physiological and behavioral effects of field research methods in the wild. Here, we examine how the stress response, i.e., fecal cortisol, and behavior of Ugandan red colobus monkeys (Procolobus rufomitratus) in Kibale National Park are affected by chemical immobilization and collaring, i.e., capture. We compare this anthropogenic stressor to a naturally occurring stressor: a chimpanzee (Pan troglodytes) predation attack. Two adult males had peak cortisol levels of 283 and 284 ng/g 2–3 d after capture, which were 190% and 182% above their baseline levels, i.e., the first sample taken immediately after capture, but these peak levels did not remain elevated. Using long-term data, i.e., 11 mo of data, we found no difference in fecal cortisol levels between 10 darted and collared individuals and 14 individuals living in the same social group that were not darted or collared. For the chimpanzee attack, peak fecal cortisol levels (147–211% above baseline) were recorded 1–4 d after the attack, but these levels also did not remain elevated for long. These data show that darting and collaring and a chimpanzee predation attempt caused an acute stress response, but neither leads to sustained elevated cortisol levels. Thus, in situations in which research contributes significantly to the conservation of primates and cannot be conducted noninvasively, capture darting appears to be a useful technique with minimal long-term effects as long as injury and mortality are avoided. However, we encourage researchers to make similar physiological and behavioral comparisons in other field studies using similar techniques to provide a better understanding of the effects of research practices on the stress physiology and social behavior of wild primates.     

Coalitional Physical Competition

A large body of research links testosterone and cortisol to male-male competition. Yet, little work has explored acute steroid hormone responses to coalitional, physical competition during middle childhood. Here, we investigate testosterone, dehydroepiandrosterone (DHEA), androstenedione, and cortisol release among ethnically Chinese boys in Hong Kong (N = 102), aged 8–11 years, during a soccer match (n = 84) and an intrasquad soccer scrimmage (n = 81), with 63 participants competing in both treatments. The soccer match and intrasquad soccer scrimmage represented out-group and in-group treatments, respectively. Results revealed that testosterone showed no measurable change. DHEA increased during both treatments in the majority of participants and the degree of change had no relation to independent variables (e.g., performance, age, treatment, outcome) or covariate measures (Body Mass Index, Pubertal Development Scale). Most boys experienced androstenedione increases during match play, but no significant differences during the intrasquad soccer scrimmage competitions. The magnitude of change differed significantly between treatments and was positively associated with age. These latter findings suggest boys’ androstenedione responses may be sensitive to competitor type (i.e., unknown competitors vs. peers). For most subjects, cortisol significantly increased during match play, decreased during the intrasquad soccer scrimmage, and differed significantly between treatments, suggesting each treatment promoted a different psychological state among competitors. Cortisol/DHEA molar ratio decreased during the intrasquad scrimmage, suggestive of a more relaxed mental state. These data shed new light on potential proximate mechanisms associated with coalitional competition among prepubescent boys, with relevance to adrenarche and life history theory.     

Characterization and Social Correlates of Fecal Testosterone and Cortisol Excretion in Wild Male <Emphasis Type="Italic">Saguinus mystax</Emphasis>

Reproductive success in male primates can be influenced by testosterone (T) and cortisol (C). We examined them in wild Saguinus mystax via fecal hormone analysis. Firstly, we wanted to characterize male hormonal status over the course of the year. Further we tested the influence of the reproductive status of the breeding female, social instability, and intergroup encounter rates on T levels, comparing the results with predictions of the challenge hypothesis (Wingfield et al., 1990). We also tested for interindividual differences in hormonal levels, possibly related to social or breeding status. We collected data during a 12-mo study on 2 groups of moustached tamarins at the Estación Biológica Quebrada Blanco in northeastern Peru. We found fairly similar T and C levels over the course of the year for all males. Yet an elevation of T shortly after the birth of infants, during the phase of ovarian inactivity of the groups breeding female, was evident. Hormonal levels were not significantly elevated during a phase of social instability, did not correlate with intergroup encounter rates, and did not differ between breeding and nonbreeding males. Our results confirm the challenge hypothesis (Wingfield et al., 1990). The data suggest that reproductive competition in moustached tamarins is not based on endocrinological, but instead on behavioral mechanisms, possibly combined with sperm competition.     

Testosterone and cortisol jointly regulate dominance: Evidence for a dual-hormone hypothesis

Traditional theories propose that testosterone should increase dominance and other status-seeking behaviors, but empirical support has been inconsistent. The present research tested the hypothesis that testosterone's effect on dominance depends on cortisol, a glucocorticoid hormone implicated in psychological stress and social avoidance. In the domains of leadership (Study 1, mixed-sex sample) and competition (Study 2, male-only sample), testosterone was positively related to dominance, but only in individuals with low cortisol. In individuals with high cortisol, the relation between testosterone and dominance was blocked (Study 1) or reversed (Study 2). Study 2 further showed that these hormonal effects on dominance were especially likely to occur after social threat (social defeat). The present studies provide the first empirical support for the claim that the neuroendocrine reproductive (HPG) and stress (HPA) axes interact to regulate dominance. Because dominance is related to gaining and maintaining high status positions in social hierarchies, the findings suggest that only when cortisol is low should higher testosterone encourage higher status. When cortisol is high, higher testosterone may actually decrease dominance and in turn motivate lower status.     

Interspecific competition between the red imported fire ant,Solenopsis invicta Buren and ghost ant,Tapinoma melanocephalum Fabricius for honeydew resources produced by an invasive mealybug,Phenacoccus solenopsis Tinsiley

In natural as in agricultural ecosystems, interactions between ants and honeydew-producing hemipterans are commonly observed. Mutualisms between invasive ants and hemipterans have been extensively studied in recent years. However, native ant species can equally exploit the honeydew excreted by hemipterans, and establish close relationships with them. Up till present, little is known about the competition between exotic ants (such as Solenopsis invicta) and its co-occurring species (e.g., Tapinoma melanocephalum) for this food resource. In this study, we compared the competitive ability of the invasive ant S. invicta and its co-occurring species T. melanocephalum in the laboratory. We also determined whether the two ant species could coexist and share honeydew resource. Our results indicate that the foraging activity of T. melanocephalum was restrained by S. invicta. Mortality of S. invicta and T. melanocephalum was significantly higher in T. melanocephalum colony case than that in other cases. The invasive ability between the two ant species was significantly different. These results suggest that S. invicta suppresses exploitation of honeydew-producing hemipterans by native ants and occupies most of honeydew resource. S. invicta could not completely drive T. melanocephalum out of honeydew competition, with small numbers of T. melanocephalum workers coexisting and sharing the honeydew with S. invicta. This finding permits a better understanding of the invasion success of S. invicta, and its ability to occupy new habitats.     

Competition-related testosterone,cortisol, and perceived personal success in recreational women athletes

Thirty-five women participating in one or more intramural flag-football games provided saliva samples before, immediately after, and 10 min after competition and completed an after-competition questionnaire appraising their own performance during the game. As seen in other studies of elite athletes, these recreational athletes, on average, showed significant elevations in testosterone (T) and cortisol (C) across the competition period – the “competition effect”. In winners and losers, T levels at all time points measured were positively related to athletes' appraisals of their own individual performance. Results from this study show that the competition effect for T and C is evident in recreational women athletes and provide preliminary evidence about the relationship between cognitive appraisal and competition-related T levels.     

Sexy thoughts: effects of sexual cognitions on testosterone, cortisol, and arousal in women

Previous research suggests that sexual stimuli increase testosterone (T) in women and shows inconsistent effects of sexual arousal on cortisol (C), but effects of cognitive aspects of arousal, rather than behaviors or sensory stimuli, are unclear. The present study examined whether sexual thoughts affect T or C and whether hormonal contraceptive (HC) use moderated this effect, given mixed findings of HC use confounding hormone responses. Participants (79 women) provided a baseline saliva sample for radioimmunoassay. We created the Imagined Social Situation Exercise (ISSE) to test effects of imagining social interactions on hormones, and participants were assigned to the experimental (sexual) or one of three control (positive, neutral, stressful) conditions. Participants provided a second saliva sample 15 min post-activity. Results indicated that for women not using HCs, the sexual condition increased T compared to the stressful or positive conditions. In contrast, HC using women in the sexual condition had decreased T relative to the stressful condition and similar T to the positive condition. The effect was specific to T, as sexual thoughts did not change C. For participants in the sexual condition, higher baseline T predicted larger increases in sexual arousal but smaller increases in T, likely due to ceiling effects on T. Our results suggest that sexual thoughts change T but not C, baseline T levels and HC use may contribute to variation in the T response to sexual thoughts, and cognitive aspects of sexual arousal affect physiology.     

Steroid Hormones and Facial Traits in The Recognition of A Potential Rival in Men

There is evidence that the cognitive skills that enable an individual to evaluate their own physical characteristics and those of others are an important strategy for recognizing a potential rival in intrasexual competition in humans. It has been shown that these strategies are facilitated by steroid hormones such as testosterone (T) and cortisol (C). This study examines whether men recognize as attractive some facial characteristics of other men that the literature reports as attractive to women when observing the faces of other men, under the hypothesis that the presence of these features indicates a potential rival. The characteristics evaluated were facial fluctuating asymmetry (FA), dominance (D), and assertiveness (A). In addition, we investigated whether the recognition of these facial characteristics depended upon the characteristics of the evaluator, that is, of the man's own FA, D, and A, or on the concentration of T and C in saliva. We found that evaluators with greater FA (asymmetric faces) and lower concentrations of C rated the faces of more symmetrical men as more attractive to women and as the most likely to represent potential rivals. Men with asymmetric faces exhibited higher levels of T than low FA males, although the difference was not significant. Conversely, men with low levels of FA (symmetric) identified the faces of more assertive men as the most attractive to women and the most likely to represent potential rivals. We concluded that men with high FA levels are more prone to recognize a potential rival in others according to female preferences, and this identification enables them to reduce the cost of competition.     

Neospora caninum and coxiella burnetii seropositivity are related to endocrine pattern changes during gestation in lactating dairy cows

Q fever is a zoonotic infection caused by Coxiella burnetii that is endemic worldwide. Domestic ruminants are a source of infection for humans. Given the suggestion that the bacterium recrudesces during pregnancy in cattle, this study was designed to determine whether C. burnetii infection affects hormonal patterns, such as progesterone, cortisol, pregnancy associated glycoproteins (PAG), and prolactin during gestation in lactating cows. Possible interactions with Neospora caninum were also explored. The study was performed on 58 gestating non-aborting cows. Blood samples for hormone determinations were collected on Days 40, 90, 120, 150, 180, and 210 of gestation. For antibody determinations, blood was collected at day 40 postinsemination and postpartum. By GLM repeated measures analysis of variance, we established the effects of production and reproductive variables as well as Coxiella and Neospora seropositivity related to changes on cortisol, PAG, progesterone, and prolactin levels. Coxiella antibody levels were significantly related to cortisol, PAG, and plasma progesterone concentrations, whereas Neospora seropositivity was linked to plasma progesterone concentrations. The interaction between Coxiella and Neospora seropositivity was correlated with cortisol and plasma progesterone levels, whereas the interaction seropositivity against C. burnetii-plasma cortisol concentration was related to plasma PAG levels. Finally, an effect of lactation number only was observed on plasma prolactin. Our findings suggest that both the N. caninum and C. burnetii infection or the presence of both modify endocrine patterns throughout gestation. Cows seropositive to both, Neospora and Coxiella, showed higher plasma progesterone levels than the remaining animals examined. Seropositivity to C. burnetii was associated with placental damage and diminishing PAG levels throughout the second half of gestation, along with increased plasma cortisol levels on Day 180 of gestation.     

Psychosocial stressor effects on cortisol and ghrelin in emotional and non-emotional eaters: Influence of anger and shame

Food consumption in stressful situations vary as a function of individual difference factors (e.g., emotional vs. non-emotional eating), and may be related to hormonal responses elicited by the stressful event. These hormonal responses may be tied to specific emotions elicited by the stressful event. The present investigation examined the emotional and hormonal (cortisol, ghrelin) responses of high and low emotional eaters following a laboratory stressor (Trier Social Stress Test; TSST). Women (n = 48) either high or low in emotional eating status were tested in a TSST or served as controls during which blood samples were taken for analysis of cortisol and ghrelin, both of which have been implicated in eating and in response to stressors. The TSST promoted elevated cortisol levels, being somewhat more pronounced in emotional than in non-emotional eaters. Both shame and anger were provoked by the TSST, and although both these emotions were correlated with cortisol levels, only anger significantly mediated the relationship between the stressor and cortisol levels. As well, baseline ghrelin levels in low emotional eaters exceeded that of high emotional eaters, and increased moderately in response to the stressor situation, irrespective of emotional eating status. Interestingly, when provided with food, ghrelin levels declined in the non-emotional eaters, but not in emotional eaters. The possibility is offered that the lack of a decline of ghrelin in emotional eaters may sustain eating in these individuals.     

The evolved psychology of voice: evaluating interrelationships in listeners' assessments of the size,masculinity, and attractiveness of unseen speakers

A growing body of research has examined how voice characteristics advertise personal dimensions relevant in mate competition and mate choice. This work has centered on two key voice features, namely, fundamental frequency (F₀) and formants (Fn), and has consistently found that speakers with low F₀, low Fn, or both are rated as being larger, more masculine, and more attractive if men but less attractive if women. However, this consistency in listeners' perceptions is not matched by an equivalent consensus in how these mate-relevant dimensions are causally related or signaled by voice characteristics. Consequently, it is critical to test whether the strong correlations in listeners' perceptions reflect reliable causal relationships between these dimensions or, alternatively, whether they reflect some perceptual or cognitive nonindependence, for example, “what is large is masculine” and “what is small is feminine.” To test this latter possibility, we report detailed analyses of interdependence in listeners' ratings of perceived size, masculinity or femininity, and attractiveness of natural and manipulated voices of the opposite sex. We found strong correlations in listeners' ratings of all three dimensions, confirming past research. Principal component analysis corroborated these interrelationships but also revealed some independence in women's ratings of men's attractiveness and additional (but weaker) independence in men's ratings of women's size. We discuss possible implications for future research on the evolved psychology of voice and whether and how it reflects adaptive functional heuristics for discriminating mates.