It’s time to finally sign up for that gym class – group fitness won hands down when pitted against solo workouts in a US study. For 12 weeks people either did a weekly 30-minute group class or trained alone, doing whatever they fancied. They rated their stress levels and quality of life mentally, physically and emotionally. After 12 weeks, the group exercisers showed significant improvements in all three measures: MENTAL (12.6 per cent) PHYSICAL (24.8 per cent) and EMOTIONAL (26 per cent). They also reported a 26.2 per cent reduction in stress. Individual exercisers worked out for longer, but saw no significant changes in any measure, except in mental quality of life (11 per cent increase).