RESUMO
PURPOSE: The purpose of this paper is to identify the factors which influence male prisoners' motivation for, and engagement in, exercise and subsequent healthy behaviours. DESIGN/METHODOLOGY/APPROACH: The first authors conducted 20 semi-structured interviews with male prisoners inside an English medium-security male prison. Interviews were recorded and transcribed, themes were identified using thematic analysis and a critical realist perspective applied to understand objective processes behind prisoners' experiences and shared meanings of exercise and engaging in healthy behaviours in prison. FINDINGS: Emerging themes indicate that in the context of healthy behaviours male prisoners aspired to a masculine ideal that was characterised by a culture of either adaptive behaviours, or maladaptive behaviours. The former fostered an adaptive exercise culture which promoted psychological well-being through an autonomy-supportive environment, consequently internalising motivation and minimising perceived barriers to engaging in healthy behaviours. Conversely, a culture of maladaptive behaviours fostered a maladaptive exercise culture which led to negative psychological well-being, underpinned by external forms of motivation which emphasised barriers to engaging in healthy behaviours. PRACTICAL IMPLICATIONS: Findings emphasise the need for prisons to promote an internal perceived locus of control for male prisoners when engaging in healthy behaviours. ORIGINALITY/VALUE: The authors adopt a rare interdisciplinary approach combining a psychological theory of motivation and criminological perspectives of prison culture to understand how best to minimise the impact of prisons as an institution on the psychological well-being of male prisoners.