In this talk I will present recent research on social bonding in the context of fatigue, effort, energy and performance in exercise. “Exercise” is broadly construed, incorporating aspects of human activity traditionally siloed within different academic disciplines. Our earlier work into the effects of joint exertive activity on social bonding led us to examine, in turn, how bonded sociality alters the psychobiology of exercise performance. I will discuss recent evidence for this “Social Brawn Hypothesis”, which situates buffering and energising effects of social bonding on exercise performance within a broad theoretical framework that integrates perspectives on evolution, sociality, cognition and energetics. The work potentially has broader implications for accounts of how mind, body and sociality combine in daily life and cultural evolution.