Integrating UTAUT2 and VAM to explain intention to use AI fitness coaching: The roles of perceived value and privacy, and the moderating role of EWOM

Abstract

In the context of rapid digital transformation in Vietnam, AI fitness coaching is increasingly gaining attention as a technology-driven solution for personalized fitness management and health-related behavior support. However, empirical evidence on the factors shaping users’ intention to use this service remains limited. To address this gap, this study integrates the Unified Theory of Acceptance and Use of Technology 2 (UTAUT2) and the Valuebased Adoption Model (VAM) to examine the determinants of intention to use AI fitness coaching. It also investigates the moderating role of electronic word-of-mouth (EWOM) in the relationship between perceived value and intention to use. Data were collected through direct, on-site administration of a structured questionnaire to 537 fitness users across nine private fitness centers in Ho Chi Minh City, Vietnam. Partial Least Squares Structural Equation Modeling (PLS-SEM) was used to validate the measurement model and test the proposed relationships. The findings indicate that perceived value serves as a central mechanism explaining intention to use. Specifically, performance expectancy (β = 0.373, p = 0.000), effort expectancy (β = 0.252, p = 0.000), and hedonic motivation (β = 0.179, p = 0.000) positively influence perceived value, whereas perceived cost negatively affects it (β = -0.199, p = 0.000). In addition, facilitating conditions (β = 0.224, p = 0.000) and perceived value (β = 0.313, p = 0.000) positively affect intention to use, while privacy has a significant negative effect (β = -0.186, p = 0.000). By contrast, social influence does not significantly affect intention to use (β = 0.048, p = 0.288). Importantly, EWOM positively moderates the relationship between perceived value and intention to use (β = 0.088, p = 0.004). These findings extend the integrated UTAUT2 and VAM framework to the context of AI fitness coaching in an emerging market and provide practical implications for promoting users’ intention to use such services.