The aim of this paper is to explore how older people construct their interaction in group exercise classes in geriatric rehabilitation and what is their contribution to the interaction. Discourse analysis was employed and data, consisting of seven videotaped group-based exercise sessions, were collected from 52 older people (aged 66–93 years) and nine rehabilitation professionals in seven rehabilitation centres. Four discourse categories were found. In “taciturn exercising”, older people remained verbally silent but physically active. In “submissive disagreeing”, older people opposed the professionals’ agenda by displaying reluctant consent to proposals. In “resilient endeavouring”, older adults persisted on their course of action, regardless of the disapproval of the professionals. In “lay helping”, older people initiated spontaneous encouragement, but also gave verbal and physical assistance to their peers. Older people's meaningful contribution to interaction, whilst it may challenge the institutional flow of activities, can constitute an integral part of the re-ablement process of rehabilitation.