Effects of Goal Commitment on Physical Activity in Adults

Background/Purpose: Goal setting strategy is often used to increase physical activity. While goal-setting theory suggests that an improvement in personal performance relates to specific and difficult goals, the effectiveness of a goal may not be fully explained by the level of difficulty and specificity of the goal (Locke & Latham, 1990). Research suggests that additional factors may influence goal-setting effects on performance, such as goal commitment (Locke & Latham, 2002). Even though the literature proposes goal commitment as a potential moderator of the relationship between goal and performance, much previous goal-setting research has not measured goal commitment of participants (Bravata et al., 2007). To identify the role of goal commitment in goal-setting effects, the purpose of this study was to examine the effects of goals and goal commitment on increasing physical activity.

Method: Sixty-nine middle-aged adults (54.31 ± 6.17 years, 16 males and 53 females) participated in this study. They were asked to wear a pedometer from the time they woke up until they went to bed for the next ten days and at least five days of step count were used as a baseline of their level of physical activity. Then participants were assigned into different goal groups: 10, 20, and 40 percent increase in their steps above baseline. They were asked to reach the assigned goals for at least six days for the following week. Participants’ level of goal commitment to the assigned goal was measured based on the Klein et al. (2001) survey.

Analysis/Results: Multiple regressions were performed to examine the effects of three independent variables: goal, goal commitment, and interaction between goal and goal commitment on outcome variable which is change in daily step count. The results of multiple regression showed that the model that included three predictors was significant (R² = .23, F (3, 65) = 6.617, p < .01) and explained about 23 % of the variance in change of daily steps. Goal (b= .40, p < .05) and goal commitment (b= .22, p < .05) had directs effect on change in step count. However, the interaction term between goal and goal commitment was not found as a significant predictor for performance.

Conclusions: Findings in this study suggest that goal and goal commitment are equally important factors on performance. Setting a goal and commitment to the goals are important predictors for change in physical activity level. Strategies for increasing goal commitment should be further examined.