Muscularity and Strength Affect Individual Variation in Self-Perception of Fighting Ability in Men.

José Antonio Muñoz-Reyes,Pablo Polo,Carlos Rodríguez-Sickert,Nohelia Valenzuela,Oriana Ramírez-Herrera,Paula Pavez

doi:10.3389/fpsyg.2019.00018

Abstract

Objective: There is evidence that competitive conflicts are the main form of intrasexual competition among men. The capacity to recognize visual cues of fighting ability in competitors is thought to be an important characteristic that allows men to avoid the costs of contest competition. However, for an accurate comparison to take place, individuals need to compare the fighting ability of their competitors to their own to assess this asymmetry.Methods: In order to improve our understanding of this self-assessment process, here we study the relationship between visual fighting ability cues, namely (i) muscularity, as measured with a bioimpedance device, (ii) the real capacity to inflict cost to a rival based on strength, as measured with a hand grip dynamometer (HGS), and (iii) self-perceived fighting ability, as determined with a questionnaire. The study sample was 364 men between 18 and 38 years of age (M ± SD = 22.27 ± 3.99).Results: Our results confirm the expected positive relationship between upper-body muscularity and strength, while controlling for body mass index (BMI). However, muscularity explained only around 30.2% of the variance in strength. In addition, muscularity was related to self-perception of fighting ability in our sample, its effect being partially mediated by strength.Conclusion: The more muscular men perceive their fighting ability as being greater, and not only because they are stronger (at least in the HGS task). Accordingly, it seems that men take into account the overestimation the robustness of the relationship between strength and muscularity that prevails within his peers.

Highlights

The visual signs of physical strength, such as body muscularity, are crucial to understanding how men navigate in social environments (Puts et al, 2015)
The linear regression model indicated a positive relationship between upper body muscularity, while controlling for body mass index (BMI) and age, and selfperceived fighting ability [R2 = 0.14, F(3,357) = 21.121, p < 0.001]
We tested a simple mediation model in which strength mediates the relationship between upper-body muscularity and self-perception of fighting ability, with BMI and age included as covariates

Summary

Introduction

The visual signs of physical strength, such as body muscularity, are crucial to understanding how men navigate in social environments (Puts et al, 2015). Since the study of Wilson and Daly (1985) about the young male syndrome, which applied an evolutionary perspective to explain the willingness of men to participate in risky or violent competitive interactions, many studies have inquired into the functional value of direct aggression as a mechanism of intrasexual competition (e.g., Buss and Shackelford, 1997; Archer, 2009; Goetz, 2010; de Bruyn et al, 2012; Liddle et al, 2012; McDonald et al, 2012) This pattern of behavior is expected in men since, as a general tendency among mammals, males invest less energy in reproduction, in concordance with standard parental investment model, becoming the more competitive sex (Bateman, 1948; Trivers, 1972). A dimorphic characteristic that increases attractiveness in men (Frederick and Haselton, 2007; Hönekopp et al, 2007; Crossley et al, 2012; Sell et al, 2017a), correlates positively with their mate value (Muñoz-Reyes et al, 2015), and is considered as a crucial trait driving differences in the ability to inflict cost to a rival in unarmed or armed combat (Sell et al, 2012)

Methods

Results

Conclusion