Upper Body Strength from Photo

Synonyms

Formidability assessment

Definition

Humans can reliably assess upper body strength from photographs.

Introduction

Upper body strength is the most reliable cue to fighting ability in humans (Sell et al. 2009). This is at least partially because for most of human history, the most effective fighting tactics involved using the upper body to strike and injure competitors. Given that upper body strength is almost completely determined by the size of the muscles in the upper body (Lassek and Gaulin 2009), upper body musculature is a particularly salient visual cue to an individual’s fighting ability. As such, the visual system is well designed to acquire those cues to body size and pass them along to the cognitive program that judges fighting ability.

Empirical Evidence

To test the accuracy of upper body strength assessments, researchers have extensively relied on photographic stimuli. The basic reasoning is that if cues to upper body strength are assessed visually, then humans...