This study contrasted the effects of an enhanced group intervention program against a standard group intervention, with specific reference to the influences of group cohesion on changes in health-related physical activity of older adults. Older adults (N = 122) took part in a 12-week intervention with repeated post-intervention follow-up (6 & 12 months) assessing physical activity behaviour and perceptions of group cohesion. Results indicated significant positive change (p < 0.05) across time, but a non-significant difference between groups, for physical activity behaviour. For group cohesion, results indicated a significant negative (p < 0.05) change across time and similar to physical activity behaviour, a nonsignificant difference between the intervention groups. Further research is needed to understand the mechanism that fosters group cohesion in order to develop future interventions aimed at increasing physical activity behaviour and adherence in older adults
