Background: The experience of physical activity is influenced by social relations and gendered roles. Group-based lifestyle interventions are considered effective in promoting physical activity, yet the experiences of being active with others are unknown among individuals with severe obesity. Purpose: To explore how individuals with severe obesity experience being with others during physical activity. Methods: A qualitative hermeneutic phenomenological study of repeated single gender focus group interviews was conducted with adults living with severe obesity during group-based lifestyle intervention. The Danish Data Protection Agency (J. no.1-16-02-425-15) approved the study. Results: Three themes were developed: 'Enjoying safety, kinship and belonging among peers'; 'Feeling like a failure is shameful: a sense of aversion' and 'Striving to feel at home in physical activity: needing distance from others'. The themes were merged into 'Achieving wellbeing may always be a challenge: not feeling at home in the group or in body'. Conclusion: Intersubjective and spatial dimensions of experiences are central and influence how individuals with severe obesity can feel wellbeing and 'at home' in physical activity. Physiotherapists should be aware of the individuals' vulnerability regarding feelings of failure, aversion and shame as well as awareness of gendered norms and roles.