Abstract: | Because social modeling relates to exercise behavior, the Social Modeling of Exercise Inventory (SMExI) was developed to assess this form of social influence. In Study 1a, participants (n = 294) were asked how others help them to exercise regularly. Based on these responses, Study 1b (n = 246) and Study 1c (n = 146) examined the created scale’s factor structure. Study 2a (n = 265) established reliability and validity and examined predictive power toward theoretically relevant variables. Study 2b (n = 123) validated a 7‐day response format. The SMExI demonstrated high reliability and good measurement validity. It was related to other exercise‐specific social influences, predicted the amount to which individuals engaged in regular exercise, and provided incremental validity beyond existing measures of social influence. The SMExI provides a specific instrument that can be used to examine the extent to which social modeling relates to exercise behavior. Limitations and future directions for research and application are discussed. |