The question remains as to whether adopting constrictive postures would lead to a change in salivary progesterone, thereby indicating an increase of affiliation motivation. Two others attempted to improve the original study’s setting by testing effects in more ecologically valid social contexts that bear implications for power, status and dominance, such as competition or public speaking (Smith & Apicella, 2017; Davis et al., 2017). Building on theories of embodiment, which postulate that many aspects of cognition are shaped by representations of body actions, Carney, Cuddy & Yap (2010) assessed whether exhibiting non-verbal dominant or submissive behavior, namely expanding or constricting one’s body, would induce corresponding changes in testosterone and cortisol levels. Saliva samples were taken at two different time points in a time window in which hormonal responses to stress, competition and other manipulations are known to be strongest. By testing the effects of repeated but short posture manipulations in between the blocks of a social task while using a cover story, it further fulfills the conditions previously raised as potentially necessary for the effects to occur. Interestingly enough, this translates to the hormone levels of men, especially testosterone that can be affected by the way you sit and stand. A more detailed look at the aforementioned Harvard Business School research reveals potential cognition-enhancing benefits of open, power postures (3). Her findings reveal the benefits of ‘power posing’ and more specifically, utilizing a posture that portrays confidence even when you don’t feel confident. Moreover, one of the studies observed in this scientific review reported that adult men who administered testosterone experienced an increase in optimism and confidence. What researchers found is that prenatal testosterone exposure (in the womb) has a very powerful effect on the behavior and physiology of males. A 2018 scientific review published in the Frontiers in Behavioral Neuroscience journal examined the impact of testosterone and cortisol on risk-taking (7). Yes, testosterone has a positive effect on the confidence of men, as evident by relevant scientific papers. Together, the repeated 2 min periods in which participants adopted one of two standing postures, together with the encouragement of a similar, but freely adaptable sitting position during the face categorization task, added up to a "larger dose" of posture while avoiding discomfort. Depending on the participant’s posture condition, she finally instructed participants to (1) sit upright with feet apart or (2) keep back and shoulders slumped and legs parallel or crossed during the task as far as comfortable for them, which supposedly served to "stabilize" the effect of postures on heart rate. The expansive and constrictive posture involved open or closed limbs, erect or slumped upper body and straight or downward head tilt, respectively (see Fig. 2). Given inherent biological differences in testosterone and progesterone production between men and women, analyses of these hormones need to be done separately for each sex (Stanton, 2011). Therefore, we included only male participants to achieve sufficient power with the maximum sample size possible under our feasibility constraints. Aiming for a stronger emphasis on social aspects, we made faces task-relevant, having participants categorize them according to their implicitly assigned minimal group membership. The original social filler task consisted of forming impressions of faces without providing a response, and is commonly interpreted as a "social context" in the posture literature (Cesario & McDonald, 2013; Carney, Cuddy & Yap, 2015). The study’s design met the criteria which Carney, Cuddy & Yap (2015) pointed out as potentially necessary conditions for posture effects in their response to the first non-replication.
