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date: 22 October 2019

Psychobiological Responses to Competition in Women

Abstract and Keywords

From an evolutionary perspective, questions have been raised about whether women have a psychobiological pattern similar to that of men. In humans, hormonal effects of competition and its outcome have been investigated under the biosocial status hypothesis, which proposes that, after a competition, winners would show increases in testosterone whereas losers would show reductions, and the challenge hypothesis, which emphasizes the functional role of testosterone increases in the spring to promote agonistic behavior related to territoriality and access to females. Subsequently, the coping competition model has defended the study of competition within a more general stress model, considering the psychobiological responses as part of the coping response. This chapter shows that women investigations are increasing in number in recent years and that, in competitive situations, they present coping strategies with a psychobiological response pattern that can be enlightened by the coping competition model.

Keywords: women, competition, psychobiological responses, variables, coping competition model

Introduction

In 1987 … it was still acceptable to exclude women from research because of the “noise” that might be introduced in the data due to their menstrual cycle and associated hormones. In 1993, … the policy … became that women must be included … the noise turned into orchestrated notes of independent variables that have spurred entire areas of inquiry in the field of women’s health…. Thus, the noise crescendos into a melody of hope that the next decade of women’s health research will provide as much information about improving the lives of women as the previous decade has provided about the causes our illnesses.

Girdler, 2005, p. 1

In 2005, Girdler emphasized the lack of studies on women’s health, mainly due to female hormonal changes, and the importance of including women in research. She also indicated that there was a need for studies, so that “the noise crescendos into a melody of hope that the next decade of women’s health research will provide as much information about improving the lives of women” (p. 1). This objective includes a wider range of variables in order to understand the complete picture of women’s health. The psychobiological basis of competitive behavior in women is one of the topics that has been omitted. When this type of research began in humans, it was carried out mainly in men, with only a few exceptions in recent decades. Studies on human competition have shown very complex scenarios because hormones and behavior interact in a direct and simple way, while other factors, such as cognitive and personality variables or the situation appraisal, mediate these relationships (Salvador, 2005; Salvador & Costa, 2009). Currently there are data available from sports and laboratory contests that allow us to conclude that women also compete, although at least some characteristics of their competitive behavior tend to be different from that of men.

(p. 356) In this chapter we explain the importance of competition for women and its main characteristics from an evolutionist approach. In the first part, basic concepts and definitions related to competition and sex differences are introduced from this perspective. In the second part, we present and compare the main explanatory hypotheses proposed in the literature, leading to the third part, where the main results obtained from the empirical research are introduced and interpreted. Based on the previous points, the final section is dedicated to a general discussion about the psychobiology of competition in women.

Competition as a Form of Stress

Briefly, competition involves the confrontation between two or more individuals to obtain a goal in order to achieve or maintain status. In this situation, one opponent (person or group) ends up winning, whereas the other is defeated. Therefore, one or several individuals carry out actions leading to an objective that is not possible for everyone to achieve. In addition, competition plays an important social role not only to gain primary reinforcements like food or mating but also to obtain other secondary resources (i.e., employment, promotion) that make it possible to attain the best primary resources (Salvador & Costa, 2009). The outcome can have short- or long-term consequences for the individual or individuals. This situation is clearly present in nature, where the resources are usually limited. For example, a mouse strives for food, and its motivation is primarily to avoid dying of starvation, but agonistic encounters are also motivated by the possibility of rising in the hierarchy in order to obtain better food (primary resources) or social relationships. The short-term consequences of defeat can be worse or insufficient food, whereas the long-term consequences can be immunological impairment and premature death.

Thus, agonistic behavior is an adaptive behavior that is used to reach goals because the outcome, winning or losing, affects the achievement of significant aims in the daily lives of these individuals (e.g., obtaining territory, mates, or food). From an evolutionary point of view, the importance of competitive behavior that leads to maintaining and/or rising to a higher status is clear, and it has strong repercussions for the organization of social species (Blanchard, McKittrick, & Blanchard, 2001; Koolhaas, de Boer, Buwalda, & van Reenen, 2007). In humans, men’s physiological and particularly hormonal responses associated with competition have been studied since the 1980s. Specifically, sports competition has some special characteristics that are not present in other competitive situations in humans, which make it an ideal situation to investigate psychobiological responses to competition. The most important characteristics are that the outcome is not established, the main criterion for success is merit or ability, the duration of the sports competition is limited, and, finally, the result has clear consequences because there is a winner and a loser (Salvador, 2005).

However, competition is also a social stressor (Suay et al., 1999), which means that a wide range of literature must be considered (Salvador, 2005; Salvador & Costa, 2009), and researchers must take into account competition’s potential strength and frequency in a social species. In other words, stress implies an imbalance between demands and resources, so there is a loss of homeostasis. Moreover, an individual must perceive the situation as threatening, new, or uncontrollable, which involves psychophysiological and hormonal changes. The fight-or-flight response described by Cannon (1932) immediately prepares the individual by activating the autonomic nervous system (ANS), especially the sympathetic adreno-medullar system (SAM), with increases in blood pressure, heart rate, and secretion of catecholamines into the bloodstream, among other responses, in order to mobilize energy. In addition, the hypothalamus–pituitary–adrenal (HPA) is activated, increasing the levels of cortisol (C), a catabolic hormone that supports the SAM to increase the available energy. This is essentially the basic physiological response to stress. However, in this chapter we focus on social stress, which has a more complex pattern because the social stimuli that are capable of being sources of stress require processing and depend on many contextual and experiential cues. In this sense, Huether (1996) highlighted the value of psychosocial stress as a trigger for adaptive behavioral modifications. The primitive stress response is elicited by an external stimulus, such as a predator, and the responses are limited, stereotyped, and stable. However, the most frequent source of stress in humans comes from psychosocial conflict, such as a public speech, rather than a real threat to life (i.e., a public speech is a high psychosocial stressor accompanied by HPA and SAM activation, but the repetition of a speech can diminish the anxiety and physiological activation). Both sexes share behavioral and hormonal components to compete, but proximate evolutionary mechanisms suggest a (p. 357) sex-specific adaptation (Rosvall, 2013; Salvador, 2012), as we review in the following section.

Biological Differences Between the Sexes and Main Theoretical Explanations

In this section, we offer a concise synopsis of biological differences between men and women, focusing on the differences related to competition as a social stressor.

Are There Biological Differences That Could Affect the Way the Sexes Cope With Competition?

Competitive and aggressive behavior has predominantly been associated with males (Clutton-Brock & Huchard, 2013) who were placed by evolution into the main flight-or-fight settings. This idea is developed and explained in this section. It is assumed that the male brain is shaped to compete and that morphological (e.g., higher muscle mass) and physiological differences (e.g., testosterone [T]‌ levels) could help males to be more effective competitors than females. This does not mean that women do not compete, but, based on evolutionary theories, men would be more prone to competing than women. However, in today’s Western societies, women compete at the same levels as men because social competition depends more on psychosocial resources than on biological resources.

But are women really less competitive than men? Can we state that female brains are not adapted to competition, relative to male brains? In this section we briefly explain that men and women have developed competitive behaviors differently, depending on androgen exposure, and that we have to be cautious about extrapolating results from studies conducted with men to draw conclusions about women.

Obviously men and women are biologically different. Sexual selection operates on males and females through many morphological components (Clutton-Brock & Huchard, 2013). Specifically, the brain development of the sexes is different starting in the embryonic period. Throughout life, women have a different biological development from men, basically, although not solely, due to the influence of steroid hormones. This influence results in brain dimorphism, which complements the other effects of the steroid hormones in the development of male or female bodies. Furthermore, during adolescence, males are exposed to surges of gonadal T, while this does not occur in adolescent female bodies, where other hormones, such as estrogens, are at work. Most of these differences are explained by the so-called organizational–activational hypothesis (Arnold, 2009). In this context, we can understand that there are sex- and individual-specific behavioral and neural responses depending on the effect of T throughout the lifespan. Thus, fetal T levels are significantly responsible for the maturation of the neural circuitry of the brain (Arnold & Breedlove, 1985; Phoenix, Goy, Gerall, & Young, 1959), making the brain more sensitive to T throughout one’s life. Taking into account that in early studies T was found to be involved in aggressive and dominant behavior (Mazur & Booth, 1998), and later related to social status hierarchies (Eisenegger, Haushofer, & Fehr, 2011), and that in male mice T has rewarding properties (Arnedo, Salvador, Martínez-Sanchís, & Pellicer, 2002), this hormone must leave a trace that shapes men’s behavior differently from women’s.

If we look further, most brain regions related to the stress response circuitry are sexually dimorphic in animals and in humans. Subcortical areas, such as the central amygdala, hypothalamus and hippocampus, and cortical areas, such as the orbitofrontal cortex or prefrontal cortex, are directly related to physiological arousal (McEwen & Magarinos, 1997; Price, 1999). Moreover, these dimorphic regions regulate the HPA and hypothalamic–pituitary–gonadal axes (Bao, Hestiantoro, Van Someren, Swaab, & Zhou, 2005; Goldstein, Jerram, Abbs, Whitfield-Gabrieli, & Makris, 2010; Keverne, 1988; Ostlund, Keller, & Hurd, 2003; Swaab, 2004), suggesting hormonal regulation of stress response circuitry (Goldstein et al., 2010). Therefore, sex differences in the stress response circuitry are hormonally regulated via the influence of subcortical brain activity on the cortical control of arousal, which also demonstrates that females have been endowed with a natural hormonal capacity to regulate the stress response that differs from males (Goldstein et al., 2010). Apart from the differences in the brain and hormones, there is relatively consistent evidence that men are more risk-taking than women on most tasks (i.e., in economic games) and that, on average, women prefer less competitive situations than men in objective probability lotteries or high-stakes decisions (in laboratory and field situations). Moreover, these differences are stable when comparing single and married people. One possible explanation is that women experience stronger emotions than men, which affects decisions involving risk (Croson & Gneezy, 2009). Specifically, women report more anxiety and fear in anticipation of negative outcomes (Brody, 1993), and they have a greater fear of losing, because they (p. 358) are less confident in uncertain situations than men (Croson & Gneezy, 2009). However, this decision-making is also affected by the menstrual cycle (Chen, Katušcák, & Ozdenoren, 2013). During the menstrual cycle, levels of estradiol, progesterone, the luteinizing hormone, and the follicle-stimulating hormone change. It has been suggested that women change their decision-making according to their menstrual cycle phase. Thus, naturally cycling women bid (on the lottery) significantly higher in the first part of the menstrual cycle, when estrogen levels are high, than in the second part of the cycle, when estrogen levels are lower and progesterone levels are higher (Chen et al., 2013). Furthermore, women are more predisposed to engage in risky behavior during their fecund phase, around the ovulatory period. Thus, from an evolutionary point of view, Pearson and Schipper (2013) have interpreted these risky behaviors as a way to increase the probability of conception during this specific menstrual phase. Consequently, sex differences in risky decision-making would depend on the phase of the menstrual cycle.

Therefore, there are some neuroendocrine differences between men and women that may predispose them to behave differently. We next address the issue of whether morphological and physiological factors could modify the way the sexes cope with life events, including competition for resources.

Main Theoretical Frameworks in Competition Research: Why Men and Women Respond Differently to Competition

In social neuroscience, two hypotheses analyze how sex differences influence adaptive behavior: the fight-or-flight and tend-and-befriend strategies. As Taylor et al. (2000) point out, “Survival depends upon the ability to mount a successful response to threat. The human stress response has been characterized as fight-or-flight (Cannon, 1932), and has been represented as an essential mechanism in the survival process” (p. 411). This type of response has mainly been studied in males, particularly in male rats. In our species, it has been studied in men but less so in women. However, natural selection has caused both men and women to be effective competitors, although the paths they use may be different due to sex-specific reproductive strategies (Benenson, 2013). Male mammals typically invest less in their offspring than females do, and they can potentially have more offspring (Bateman, 1948). Female mammals, however, must invest more time and energy in caring for their offspring, be more selective about their partners, and compete for the resources they need for their offspring to mature (Lancaster & Lancaster, 1983). Thus, Taylor et al., from a meta-theoretical perspective, assume that successful responses pass through generations, according to the principles of natural selection, and what is most adaptive for men might not necessarily be adaptive for women. Specifically, they propose that the female human response is not characterized by fight-or-flight, as assumed in the literature, but by tend-and-befriend, suggesting that protection and care of offspring and a desire for membership (i.e., creating and maintaining relationships with other women in a small group) are adaptive behaviors for females.

Next we introduce a more detailed explanation of differences between sexes in response to stress. In males, the fight-or-flight strategy is linked to sympathetic activation and to an organized pattern of behavior, due in part to activating androgens. The female response is not as clearly related to androgens but rather to another hormone (oxytocin), at least partially, and it is more associated with protective behavior (Archer, 1991). In this sense, the fight response can be maladaptive for females (i.e., females are usually not as strong as males) and, although the flight response in females may seem more appropriate than the fight, it is not a dominant response; if a female is caring for her offspring, flight would mean abandoning them (Taylor et al., 2000). In a complementary way, both sexes have androgen receptors in the nervous system and in peripheral tissues exhibiting behavioral or physiological responses to T (Rosvall, 2013). Thus, androgens could have effects on both males and females. Nonetheless, Taylor et al. sustained that in females, tend-and-befriend behavior could be more adaptive than the fight-or-flight response to reach their vital objectives, such as the care of their offspring. They argue that it is more adaptive for women to look for protection in safe contexts (e.g., look for affiliation with other female groups to protect themselves and their offspring from predators), as it is not necessary to compete when females can take advantage of other alternatives (in the previous example, the group would reduce the probability of confrontation with the predator). Research in humans concludes that the desire to affiliate with others is more pronounced in women than in men, and it is one of the most robust sexually dimorphic behaviors (Taylor et al., 2000). Moreover, women’s tendency to engage in affiliative behavior while under stress causes them to bond with other women (Schachter, (p. 359) 1959). Although Taylor et al. (2000, 2002) do not deny that women are competitive, they support the idea that there is no basis for direct aggression between females from an evolutionary perspective. However, this argument allows that competition is in the behavioral repertoire of women; according to Geary and Flinn (2002), women compete for social and material resources by showing another type of aggression (i.e., relational). In fact, Campbell (2013) states that women compete, and it has been asserted that in women, relatively low-risk competitive strategies are favored by means of indirect aggression, which is a low-cost but effective form of competition (Stockey & Campbell, 2013).

These approaches to understanding the causes of behavior are based on attempts to explain the evolutionary, adaptive strategies employed by men and women. However, they need to be accompanied by other approaches that make it possible to analyze the proximate causes (how a mechanism interacts with environment), which depict the biological process that contributes to a response, such as to maintain one’s status. From an empirical point of view, it is difficult to transfer critical concepts like survival to routine investigation. Thus, from a theoretical perspective, several hypotheses have been proposed to test how competition exerts its effects in humans and how these hypotheses can help to explain evolutionary adaptive strategies (Salvador, 2012).

Hypotheses Used to Frame Empirical Studies in Competition Research

In the 1970s and 1980s, important research on agonistic behavior in rodents and nonhuman primates was carried out by studying how T was involved in changes in hierarchical status. One study with rats showed increases in T after winning and decreases in T after losing an encounter (Schuurman, 1980). Moreover, when T levels were exogenously manipulated, the same results were found. These studies, along with others in nonhuman primates (Bernstein, Gordon, & Rose, 1983), pointed to T as the most important factor related to social status, and they delineated the way hierarchies were constructed in several species. These findings were also used to try to explain human hierarchies. In this context, the biosocial status hypothesis was formulated by Mazur (1985). According to this hypothesis, victory would induce T elevations in subjects, making them more likely to engage in future agonistic encounters in order to maintain or increase dominance, whereas T decreases were expected in losers, who would develop submissive behavior (see Figure 20.1). Moreover, winners must experience less stress and losers must experience more, which would be reflected in stress hormones, such as C in the case of humans.

Psychobiological Responses to Competition in WomenClick to view larger

Figure 20.1 Mazur’s biosocial status hypothesis.

The victory from agonistic encounters or competitions between males promotes increases in T and diminutions in C. In contrast, defeat leads to a diminution in T and increase in C. The outcome influences future competitions.

In the 1990s, another important hypothesis was formulated in relation to T and behavior: the challenge hypothesis (Wingfield, Hegner, Dufty, & Ball, 1990). It emerged from the observation of behavior in monogamous birds and highlighted the role of T changes to favor aggressive behaviors related to territoriality, dominant behavior, or protection of offspring. According to this hypothesis, T increases occurring in the spring are responsible for the behavior of these birds (i.e., 20 species of captive and free-living populations) at this time of year. Thus, social interaction affects androgen levels in males, which should be high when they have to fight for resources (e.g., family, territory, or status). The pattern could be the same in females, depending on the species (Wingfield et al., 1990).

The challenge hypothesis has also been used to explain the relationship between T and some behaviors in humans (van Anders & Watson, 2006). In specific situations, the functional value of T would favor aggressive behaviors that serve to compete for territory or mating and are considered positive or adaptive. Archer (2006) explained that T in humans could also be involved in situations where honor or personal merits are important. However, having high levels of T for long periods (p. 360) of time could become negative for the individual. After the administration of exogenous T, subjects are less sensitive to punishment and more sensitive to reinforcement, favoring risky behaviors in both men (Archer, 2006) and women (Van Honk et al., 2004).

Both of these hypotheses focus on the role of T in competition or dominance, mainly based on observations from nature and studies in different contexts and species. However, as stated earlier, other attempts have also been made to explain competition as a social stress response, including, apart from hormones, psychological and autonomic responses. There is a lack of clear, consistent findings regarding the T response to competition and its outcome in humans. For example, some studies found increases in T after winning, others found no differences between winners and losers, and still others found increases in losers (Salvador, 2005; Salvador & Costa, 2009). This inconsistency led to Salvador’s proposal to integrate competition within a more general stress model.

This model (see Figure 20.2) incorporates subjective processes, especially appraisal, based on the consideration that previous results on this topic can be better explained as a part of the coping response to competition (see Salvador & Costa, 2009). Based on this coping competition model, it is necessary to consider not only the outcome obtained but also the way the individual copes with competition. The model considers the initial step of appraisal, which begins before the competition and includes some distant factors that influence the analysis of the situation, such as status, previous experience, personality, and generic skills. These characteristics affect the specific situation in which other cognitive variables, such as expectancies, motivation, ego involvement, or self-efficacy, lead to a specific appraisal. In sum, if the individual appraises the competitive situation as important, controllable, and dependent on his or her own effort (i.e., as a challenge), an active coping response pattern is more likely to be adopted. This pattern would be characterized by increases in T, sympathetic nervous system activation, and positive mood, with no clear effects on C. All these responses would increase the probability of victory, depending on the nature of the competition. By contrast, a threat appraisal would drive an individual into a passive coping response pattern, characterized by insufficient T and sympathetic (p. 361) nervous system activation and increases in negative affect and C levels, and these responses would increase the probability of defeat (Salvador, 2005). This model emphasizes the cognitive appraisal of the specific situation, which begins before the competitive situation, at a conscious or preconscious level. Subsequently, the outcome of the situation also involves cognitive appraisal, which influences future competitions. In other words, a cognitive reappraisal emerges from the causal attribution, the satisfaction with the outcome or the reward, complementary to the real outcome, and these variables have an influence on the individual (Salvador, 2005; Salvador & Costa, 2009).

Psychobiological Responses to Competition in WomenClick to view larger

Figure 20.2 Salvador and Costa’s coping competition model.

Competition begins before the event with cognitive appraisal, whereby a situation can be viewed as a challenge or threat. A challenge appraisal is related to an active coping response with increases in T, in sympathetic nervous system, and in positive mood, increasing the probability of victory. A threat appraisal leads to a passive coping response with diminutions or insufficient increases in T and sympathetic nervous system, increases in C and in negative mood, which increases the probability of defeat. After competition, the appraisal influences future competitions, in proximal contest and even in distal ones.

Both the biosocial status hypothesis and the challenge hypothesis are applicable to females. However, sex differences in the competitive stress response have been found, related to different evolutionary functions (Troisi, 2001), which means that, in general, women invest more time and energy in attracting partners, developing social networks, and taking care of offspring than men, who are more likely to engage in competition to reach or maintain status. Competitive contexts are not exclusive to men, although they are probably somewhat different in women. Furthermore, competition for limited resources drives both natural and sexual selection; even though both men and women can compete, the nature of their competition may differ, especially in response to environmental variations (van Anders & Watson, 2006). However, some contests are common to both sexes, especially in Western societies, where men and women share academic or intellectual tasks, or even sporting events, so that competition on these tasks could be fairly similar for both (Cashdan, 1998).

Psychobiological Responses to Competition in Women

Important studies on competition in women, as well as those that include comparisons with men, exist. Since the 1990s, several studies about women and competition have been carried out in sports and laboratory settings. This section presents an explanation and interpretation of the main results in light of the theoretical explanations: the biosocial status hypotheses, the challenge hypotheses, and the coping competition model, described earlier.

Initially, the main theories on competition defended the possibility of being applicable to females as well as males (Mazur, 1985; Wingfield et al., 1990). However, as mentioned, research on competition was mainly carried out on men, with only a few studies addressing women. Those that mentioned women mostly did so in the context of sports (see Table 20.1).

Women’s endocrine response to competition has been studied, measuring T and C in saliva, in several sports such as rugby (Bateup, Booth, Shirtcliff, & Granger, 2002), soccer (Edwards, Wetzel, & Wyner, 2006; Oliveira, Gouveia, & Oliveira, 2009), and volleyball (Edwards & Kurlander, 2010). Generally, competition heightens T levels, regardless of the outcome (Bateup et al., 2002; Edwards & Kurlander, 2010; Edwards & O’Neal, 2009; Edwards et al., 2006; Hamilton, van Anders, Cox, & Watson, 2009). These results do not support the biosocial hypothesis, but they are compatible with the challenge hypothesis. The latter defends the functional significance of the T increases, as it is linked to competitive and aggressive behaviors. In a few studies, higher T levels were found in winners compared to losers (Jiménez, Aguilar, & Alvero-Cruz, 2012; Oliveira et al., 2009).

Bateup et al. (2002) were the first to confirm T changes in real competitive situations involving five rugby league matches with high physical and psychological implications. These changes were not related to the outcome or to performance self-assessments (labeled the “competition effect,” i.e., competition elicits more of a hormonal response than the final outcome does). Later, Edwards et al. (2006) explained the T increases in competition based on their functional significance, relating them to dominant behavior, physical risks, and better reaction time and spatial memory. Hamilton et al. (2009) reported significant T increases, unrelated to outcome, in wrestling, an individual sports competition, pointing to a link between individual head-to-head competition and T in women.

Soon after, the “winner effect” (a hormonal response only for winners) was found in a competitive situation with high personal involvement, where the outcome had clear and especially important consequences. The situation involved a change of status in a final soccer competition (Oliveira et al., 2009). However, the same effect was found in a competition without these relevant implications (Jiménez et al., 2012).

The importance of the type of event has been emphasized in the T anticipatory response. Increases in T during the warm-up period before competition have been reported in several competitions, in comparison with another, more neutral day, although the increase appeared only in women who believed that they were actually going to compete and not (p. 362) (p. 363) in those who did not go on to play (Edwards & Kurlander, 2010). These anticipatory increases may stem from physical exertion or from the psychological effect of preparing for competition. Kivlighan, Granger, and Booth (2005) reported a more complex response pattern, depending on previous experience. They found that precompetition T was lower than baseline (collected on a nonexercise, noncompetition day, at the same hour as the competition) and that T levels and rises predicted lower performance in novice women but not in varsity women.

Table 20.1. Summary of Studies on the Influence of Competition on Hormonal Response in Women.

Studies

N and Sex

Experimental Situation

Variables and Measures

Results

SPORTS

Bateup et al., 2002

17 ♀

Rugby (in 5 meets)

Tsal, Csal: 15 min before, after match

↑T and C after match

Kivlighan et al., 2005

23 ♂, 23 ♀

Rowing ergometer

Tsal, Csal: before, 20 min after, 40 min after

♀: ↓T, ↑C

Edwards et al., 2006

22 ♂, 18 ♀

Soccer competition

Tsal, Csal: 1 h before, 20 min after

♀: ↑T and C after match

Filaire et al., 2009

8 ♂, 8 ♀

Tennis competition

Csal:

Resting day: 08:00 h, 20:00 h

Compete: 08:00 h, 1 h before, 10 min before, 10 min after, 1 h after, 20:00

C: ↑L, ♂ and ♀

C: ↑ competition day

Oliveira et al., 2009

33 ♀

Soccer competition (final)

Tsal, Csal: 30 min before, 30 min after

T↑ W: ↓L: C: ↑ marginal L

Hamilton et al., 2009

13 ♀

Wrestler (2 meets with different result)

Tsal: 20 min before, 10 min after

↑T after match

Edwards & O’Neal, 2009

80 ♀

Soccer, volleyball, softball, roller derby

Tsal: Before and after competition, winners and losers

↑T after match

Edwards & Kurlander, 2010

  1. (a) 15 ♀

  2. (b) 8 ♀

  1. (a) Volleyball: competition and practice

  2. (b) Tennis: match and practice

  1. (a) Tsal, Csal: before warm-up, mid-warm-up, after competition

  2. (b) Tsal, Csal: prior warm-up, after warm-up, prior doubles competition, after single competition

    Booth: Tsal, Csal: before and after a practice session

  1. (a) W: ↑T and C after match ↑T and C after practice

  2. (b) L: ↑T after warm-up, doubles, and singles, ↑C after doubles

    ↑T after practice

Jimenez et al., 2012

27 ♂, 23 ♀

Badminton elite competition

Tsal, Csal: 40 min before and 40 min after competition

W: ↑T in ♂ and ♀

L: ↓C in ♂ and ♀

LABORATORY

Mazur et al., 1997

28 ♂, 32 ♀

Tennis video game

Tsal, Csal: 20 min before, 8 min after explanation, half a task, 10 min after, 20 min after

♀: T and C n.s.

van Anders & Watson, 2006

  1. (a) 37 ♂, 38 ♀

  2. (b) 31 ♂, 43 ♀

Computed vocabulary

Outcome (a) real, (b) random (manipulated)

Tsal before and after

(a) ♀: T n.s.

Costa & Salvador, 2012

40 ♀

Face-to-face paper-and-pencil competition

Tsal, Csal 45 min before, just before and after task, 15 min after, 30 min after

HR before, during, and after task

BP 45 min before, just before, after task, 5 min after

W: ↑T, HR, SBP

Note. Studies are divided in sport and laboratory settings, with characteristics of each investigation detailed to include sample size, experimental situation, variables and measures, and outcome results.

♀ = female; ♂ = male; Tsal = salivary testosterone; Csal = salivary cortisol; T = testosterone; C = cortisol; min = minutes; h = hours; W = win; L = loss; n.s. = not significant; HR = heart rate; BP = blood pressure; SBP = systolic blood pressure.

To analyze the function of the T changes, some studies have measured several psychological variables in real-life competitions and in the laboratory. T levels have been related to the expression of competitive and aggressive interactions (Cashdan, 2003), to dominant behavior (Edwards et al., 2006), and to the need to dominate or influence others, reinforcing competitive and aggressive behaviors (Schultheiss, Dargel, & Rohde, 2003; Schultheiss, Wirth, & Stanton, 2004). Likewise, T administration promotes a motivational balance, with a reduction in punishment sensitivity and heightened sensitivity to reward dependency (van Honk et al., 2004). Moreover, an association between T, mood changes, and performance has been found in sports (Oliveira et al., 2009) and laboratory (Costa & Salvador, 2012) competitions, pointing out that mood changes may play a role as modulators of this response. Additionally, precompetition T levels have been related to connectedness or bonding with teammates in rugby (Bateup et al., 2002), volleyball (Edwards & Waters, 2003), softball (Edwards & Weiss, 2005), and soccer (Edwards et al., 2006), providing evidence of a relationship between status or dominance and T in female team sports.

The vast majority of studies on female sports competitions have included C, along with T. Initially, the role of C was investigated under the assumption that losers should experience more stress and, therefore, C increases would be expected, as predicted by Mazur’s (1985) biosocial hypothesis. On the other hand, the functional significance of elevated C levels has been related to the availability of energy, activating and maintaining increases in blood pressure and glucose in the blood (Suay & Salvador, 2012). C participates in the physiological and behavioral response to physical challenges (p. 364) and physiological stressors, altering mood, memory, and behavior (Erickson, Drevets, & Schulkin, 2003). In this sense, C increases would prepare individuals to facilitate the response to competition. For example, Salvador et al. reported that a subgroup of judo players who displayed higher C levels, along with T increases and higher motivation to win scores, also obtained the best outcome (Salvador, Suay, González-Bono, & Serrano, 2003). However, extreme elevations of C may lead to poor performance because they interfere with cognitive processes (Erickson et al., 2003).

During sports competitions, C levels usually increase, although these increases are not significantly related to outcome (Edwards et al., 2006; Filaire, Alix, Ferrand, & Verger, 2009; Kivlighan et al., 2005). Findings are inconsistent and show C increases in winners and losers but more so in losers (Bateup et al., 2002), increases only in losers (Filaire et al., 2009; Jiménez et al., 2012; Oliveira et al., 2009), and increases only in winners (Edwards & Kurlander, 2010). These inconsistent results are difficult to interpret; therefore, the assessment of other psychological variables may be beneficial in helping to explain these C changes.

One such variable could be experience. Anticipatory C responses unrelated to outcome are higher in novices than in veterans (Filaire et al., 2009; Kivlighan et al., 2005). Filaire et al., while studying C and anxiety as a sensitive index of stress, found an increase in C prior to competition, which they explained is an indicator of a high stress level. Thus, a greater increase in C during the game has been related to the players’ impression that the opponent is challenging (Bateup et al., 2002).

Therefore, C seems to have paradoxical effects on competition. On the one hand, positive responses to competition may increase C levels in order to mobilize energetic resources; on the other hand, appraisal of the situation with high anxiety, unpredictability, or negative mood also increases C levels. Furthermore, the dual imbalance hypothesis proposes that T increases in competition only when C levels are low, pointing out the relationship between the two hormones (Mehta & Josephs, 2010). In fact, in a large sample of soccer, volleyball, softball, and tennis athletes, women with low C levels before competition showed higher T responses to competition, although outcome was not included in the study (Edwards & Castro, 2015).

In sum, a number of studies on different sport competitions have found a competition effect, with increases in T and C in women. In all of these cases, women belonged to a fairly specific group; they were young and usually varsity sportswomen, with considerable previous experience and an enhanced physical condition. These factors have been shown to influence the hormonal response to stress (Salvador, Simón, Suay, & Llorens, 1987). Furthermore, some of these sports require considerable physical effort and a high level of fitness (e.g., rugby, soccer, and wrestling). It remains to be determined whether these findings can be extended to other groups of women with different characteristics.

Although the sports context allows a high degree of ecological validity, because athletes are usually measured in real competitions where the outcome has short-term consequences, researchers in the laboratory have greater control over all the variables and can take a larger number of measurements (although competition is usually promoted through task instructions and/or a monetary reward). We agree with Kivlighan and Granger (2006) about the importance of recording complete hormonal measures, along with ANS responses. In the next section, we describe the results on the role of hormones and the ANS in laboratory competitions and their outcomes.

A few studies have been carried out in the laboratory with female university students, employing different competitive tasks in order to analyze hormonal responses to competition. For example, in competitions employing computer games, no changes in T or C responses were found to be linked to the outcome (Mazur, Susman, & Edelbrock, 1997; van Anders & Watson, 2006).

In a similar vein, we measured T, C, heart rate, blood pressure, and mood responses to competition via a paper-and-pencil task completed by young female university students. The results showed two response patterns: one related to passive coping, which combined state anxiety, negative mood, and blood pressure, and another representing active coping, which included T, heart rate, positive mood, and better performance. This second pattern was associated with winning; additionally, the women who became winners felt higher efficacy and less frustration than the losers. In sum, we found different patterns of psychobiological responses to laboratory competition in young women in a situation requiring no physical effort (Costa & Salvador, 2012). Thus, our findings support the model described previously, in which appraisal of the situation explains the psychobiological response to competition (see Figure 20.2; Salvador, 2005; Salvador & Costa, 2009).

(p. 365) It is worth noting that there has been previous laboratory research on cardiovascular (CV) measurement. The main results revealed that CV activation is required in competitive situations and that competition could be an important factor in the etiology of CV disease (Manuck, 1994; Newton, 2009; Obrist, 1981). Competitive situations included an active coping response (e.g., arithmetic tasks), compared to other stressors where the individual had no control over the task and presented a passive coping response (e.g., the cold pressor test). Obrist (1981) reported that an active coping task elicited higher systolic blood pressure and heart rate, but less diastolic blood pressure than passive coping tasks. The former responses were a result of the influence of the beta-adrenergic receptors on the myocardium, which shortened the cardiac cycle, whereas diastolic blood pressure is less related to sympathetic influences on the myocardium. Active stressors, such as arithmetic, public speaking, video games, or time-reaction tasks, predominantly elicit these responses. However, surprisingly, there are few published studies on the CV influence on competitive stress (Harrison et al., 2001), and most of them use mixed-sex samples, which makes it more difficult to draw clear conclusions about CV responses to competition in women. There is evidence that jobs with competitive elements cause heart rate and blood pressure increases, along with a decrease in the pre-ejection period (an index of myocardial contractility and beta-adrenergic influences on myocardium; Sherwood, Light, & Blumental, 1989). On grammatical reasoning tasks, increases in heart rate and better performance were reported when subjects were told that they would be compared to others, thus introducing a competitive element into the task. On a reaction-time task in competitive (i.e., against another player) and noncompetitive (i.e., alone) conditions, an increase in heart rate was found during the task and recovery, as well as better performance, in the competitive situation (Beh, 1998). Moreover, Kivlighan and Granger (2006) emphasized that the increased activation of the sympathetic system could facilitate performance. Ritcher and Gendolla (2007) concluded that the task incentive (i.e., the reward) directly influenced CV responses to a laboratory task in young men and women. In addition to the effort required, when the incentive is important and the goal is attainable, higher reactivity appears (Costa & Salvador, 2012), as previously predicted by Obrist (1981) for moderately difficult tasks but not for very easy or difficult ones.

Along these lines, Ricarte, Salvador, Costa, Torres, and Subirats (2001) analyzed the CV response of men and women who participated in a competitive task involving a group negotiation, finding a different pattern in heart rate pattern associated with performance. Heart rate increased in subjects who adequately performed the negotiation and became winners, followed by decreases after the task once they realized they had won. By contrast, losers showed decreases in heart rate during the task. In addition, winners made more internal attributions (i.e., reporting more control over the situation) than losers. Regarding blood pressure, no significant differences based on the outcome were found. Therefore, the CV response pattern to competition was indicative of beta-adrenergic activation. Other studies found that in the noncompetitive (i.e., performing the task alone, not against another player) condition, the CV response was lower than in the competitive condition (Harrison et al., 2001; van Zanten et al., 2002). A study with women found that the effort required was related to heart rate and systolic blood pressure responses; however, no differences were found in the diastolic blood pressure (Wright, Killebrew & Pimpalapure, 2002).

Finally, Peretti (1971) found that women responded faster under competitive conditions, while men did not show differences in performance. Peretti concluded that women felt more anxious in the competitive situation and, consequently, increased their surveillance and performance, although no sex differences were found in another study (Palmer & Folds-Bennett, 1998).

In sum, competition to reach goals or obtain resources requires CV activation, but this adaptive response could become a health threat when activated continuously. For example, dominance has been related to greater vulnerability to developing CV disease (Newton, 2009; Shapiro, Goldstein, & Jamner, 1995), and evaluations of personal resources and situational demands are associated with different autonomic and endocrine patterns (Seery, 2011). Few studies have addressed the influence of competitive stress on CV measures, and they are limited to laboratory studies. In general, higher heart rate and blood pressure responses on competitive tasks than on noncompetitive tasks have been described (Beh, 1998; Harrison et al., 2001; Sherwood et al., 1989; van Zanten et al., 2002; Wright et al., 2002). Furthermore, laboratory studies have introduced parameters that need to be considered when measuring the CV system, (p. 366) suggesting that beta-adrenergic activation is associated with performance and outcome.

Several moderating variables may help to explain the response to competition and its outcome in women. First, motivation, measured directly, as in the study by Costa and Salvador (2012), or indirectly, as the result of an objective situation like a final league game (Oliveira et al., 2009), is a necessary factor in obtaining involvement and, consequently, a response to competition. Other factors evaluated in the literature are the emotional changes in competition, as increases in positive mood have been described in real competitions and in laboratory settings, or bonding and relationship with others in team sports. Moreover, self-efficacy, seldom measured, is another variable that could help explain these results. Recent data indicate that self-efficacy is positively related to T levels, positive mood, and performance in a laboratory competition in women (Costa, Serrano & Salvador, 2016).

Conclusion

After reviewing the scientific literature on the psychobiology of competition in women, it is clear that there is an increasing interest in studying women’s responses in these types of situations. In our opinion, this increase is related to the awareness and recognition of sex differences in the variables that must be controlled in order to draw valid conclusions about women. Social neuroscience has used all these advances to create a more comprehensive vision of the role of both sexes in our complex contexts. Decades of studies on sex differences have produced a clearer scenario in which to study both men and women in social interactions. Thus, women’s psychobiological responses to competition could be different from men’s, although a similar pattern has also been reported, probably related to the different contexts where the competitions took place. Moreover, although no clear differences in ANS have been found, a slightly different response patterns seems to exist between the sexes.

In spite of the minor role of androgens in the female brain, it seems that, at a physiological and behavioral level, they activate similar responses to those of men, depending on the amount and the vital moment when they are activated. Androgens produce similar effects in both sexes, although in women they are modulated by female hormones and conditions (Ketterson, Nolan, & Sandell, 2005; Rosvall, 2013). When men and women compete, similar hormones are involved, although dimorphic structures and their physiological products modify the degree of influence of these hormones. In addition, cognitive processes should be included in the analyses in order to correctly interpret the behavioral responses and their physiological correlates. In this regard, Rosvall (2013) argued that greater attention should be paid to multiple analyses (i.e., from hormones to genes or intra-individual variations) in trying to understand the complex mechanisms underlying intersexual coevolution and, therefore, competition.

It is worth noting that age is also a very important variable that needs further study in relation to responses to competition. The studies described here have mainly employed samples of young adults. It is possible that these women are at a point in life that involves high competitiveness in terms of their careers, the search for a partner, and the formation and reaffirmation of social and family links. Therefore the existence of differences in other life-cycle periods is plausible.

Overall, three main hypotheses have been defended in the field of the psychobiology of competition. The first and most predominant is the biosocial status hypothesis, although most research results do not support it. Another is the challenge hypothesis, which emphasizes the functional changes in T. Several studies in women have reported increases in T after competition, although it would be an a posteriori explanation. A third position has adopted a broader approach from human stress theories; it does not deny the previous models but instead tries to complement them. Thus, the coping competition model contextualizes the different results and points to the importance of cognitive appraisal in understanding the psychobiological responses to human competition. In this sense, competition begins when the individual anticipates a contest, activating cognitive mechanisms that can be conscious or preconscious. His or her appraisal depends on proximal factors (such as who the opponent is or how important the competition is) and on indirectly related factors (such as characteristics of personality, social abilities, or previous history of successes and failures). Finally, these cognitive processes lead to a biological and emotional response that ultimately may help or impair performance. In general, it is plausible to suppose that an active coping strategy related to increases in T and positive mood would increase the probability of victory. However, the opponent is an uncontrollable variable in the equation, and, therefore, victory is not always achieved. Furthermore, the competition does not end with (p. 367) the outcome because the attributions and satisfaction with the outcome obtained could also influence and affect future competitions. This model has found support in some recent studies in men and women.

In conclusion, more studies are needed to achieve a more complete understanding of which hormones influence female competition and in what way. In this regard, we suggest a comprehensive model that includes hormones, autonomic responses, and, especially, cognitive variables that would explain how women (and men) cope with competition. It should include motives and expectations (and their associated emotional responses) about future competitions and the appraisal of past competitions, in order to obtain a broader view of the complex response pattern involved in competition. Moreover, the attempt to understand the evolutionary development of social status among individuals, and its proximal and distal factors, should be taken into account. Many of the studies presented here focus on variables that affect a single competition (proximal context). However, we also have to consider how the outcome of a single competition (and its cognitive and emotional interpretations) affects future competitions, because experience is fundamental in human behavior. Studying this question would make it easier to discover whether men and women have different response patterns to competition and whether this response is motivated by different evolutionary cues.

Acknowledgments

We thank Ms. Cindy DePoy for the revision of the English text and the funding sources that supported the investigations on the psychobiology of stress and competition: the Spanish Education and Science Ministry (Grants BSO2000-12068, SEJ2007-62019/PSIC, PSI201021343) and the Generalitat Valenciana (Grants PROMETEO2011-048 and ISIC2013/001).

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