Self-selected And Prescribed Intensity Exercise Interventions To Improve Physical Activity Behavior Among Inactive Retired People

Background:As aging,it is very important for inactive retired people to increase their physical activity.Current group-based exercise programs were reported increasing physical activity but failing to maintain behavior over time.This study explored the effectiveness of two intensity-oriented exercise interventions that are used to improve individual's positive affect to exercise and thus increasing their exercise self-efficacy and the persistence of physical activity.Design:A randomized controlled trail was designed with a 12-week group exercise intervention and 3-month follow-up by phone calling.Inactive retired participants were randomly divided into two study arms:self-selected intensity group and prescribed intensity group(prescribed as moderate intensity monitored by Rating of Perceived Exertion).The 12-week interventions of both self-selected and prescribed intensity exercise was imposed as aerobic walking for 3 times per week with 50-minitue for one session.Their daily step counts(primary outcome measured by Yamax pedometers),the affect(primary outcome measured by Positive Affect and Negative Affect Schedule)and exercise self-efficacy(secondary outcome measured by Exercise Self-Efficacy Scale)and some physical fitness indicators(including body mass index,waist circumference and blood pressure)were monitored at baseline,after 12-week interventions,and after 3-month follow-up,respectively.Results:Increased daily step counts,positive affect,exercise self-efficacy and reduced body mass index,waist circumference,blood pressure of both groups and reduced negative affect of self-selected intensity group were found significantly at different measuring times.Although self-selected intensity group had not significantly different daily step counts and exercise self-efficacy from prescribed intensity group,the former had a more positive and less negative affect to exercise.Conclusion:Self-selected intensity and prescribed-intensity exercise in moderate intensity may both improve positive affect and self-efficacy to exercise and promote post-intervention and future 3-month exercise behavior after interventions.But self-selected intensity exercise has a better impact on positive affect to exercise than prescribed intensity exercise.Findings suggest future exercise programs employ exercise intensity of self-selection to improve participants' pleasure affect to exercise.