The effect of implementation intentions on physical activity among obese older adults: a randomised control study

Physical activity is a key factor for healthy ageing and obesity management. The aim of this study was to test the effect of implementation intentions (IIs) on physical activity and body weight among inactive obese older adults.

At baseline, 101 obese (classes I and II) older adults were randomised to an experimental or a control condition. IIs were delivered in the experimental condition in addition to the common intervention activities. Physical activity (primary outcome) was assessed by means of pedometers. The effect of IIs on body weight (secondary outcome) was also evaluated.

No main effects for IIs were observed for all outcomes (ps > 0.21). A significant time × condition interaction was observed for the number of steps per day (p = 0.01). At the 6-month follow-up, the improvement in physical activity was greater among participants in the experimental condition (d = 0.59). None of the measured cognitions moderated or mediated IIs.

RESULTS suggest that IIs could be appropriate to favour the maintenance of physical activity among inactive obese older adults. However, this technique seems to have limited impacts over and above common intervention activities on weight loss.