Despite a burgeoning corpus of qualitative studies of sport and physical cultures, in-depth and embodied investigations of those requiring sustained engagement with ‘endurance work’ remain relatively under-developed. These physical cultures are sociologically interesting as they often demand of practitioners intense commitment in terms of time, energy, and (for many) finances devoted to endurance-training regimes. They also require substantial sacrifice with regard to social activities and family life, even for those not competing at elite levels. The nature of endurance and enduring still remains under-researched from a sociological and qualitative perspective, however, and we directly address this gap in the research literature by contributing fresh theoretical insights and empirical data on the lived experience of endurance in two different lifeworlds: competitive swimming and distance running. Employing a sociological-phenomenological framework, we analyse and conceptualise data derived from two separate ethnographic and autoethnographic research projects, and explore interesting commonalities in the shared lived experience of endurance and ‘endurance work’ in these two distinctive physical cultures.