2026 Theses Doctoral

Behavioral and Psychological Influences on Physical Activity: Insights from Motivation States, Stress, and Real-Time Behavior

Kim, Byul

To better explain daily fluctuations in physical activity and sedentary behavior, investigations of motivation are turning from social cognitive frameworks to those centered on affect, emotion, and automaticity. This shift of investigation on motivation and physical activity shares a common idea that human behavior is driven strongly by desires and/or similar concepts of wants, urges, and cravings.

The purpose of this dissertation was (1) to review theoretical and empirical advances in understanding motivation states for physical activity, (2) to translate and validate the Korean version of the Cravings for Rest and Volitional Energy Expenditure (CRAVE) scale, and (3) to investigate real-time relationship between stress, motivation states, and objectively measured physical activity using ecological momentary assessment (EMA) and accelerometry.

Chapter 2 synthesized conceptual frameworks and empirical findings demonstrating that motivation for physical activity fluctuates dynamically within individuals and is influenced by affective, contextual, and physiological factors. Drawing on contemporary frameworks such as the WANT model (Wants and Aversions for Neuromuscular Tasks) (Stults-Kolehmainen et al., 2020a), the Affective-Reflective Theory (ART) of physical inactivity and exercise (Brand & Ekkekakis, 2018), and the Affective–Health Behavior Framework (AHBF) (Williams & Rhodes, 2023), this chapter discussed the conceptual evolution of motivation research in physical activity, emphasizing the transition from trait-based and cognitively oriented theories to dynamic perspectives that view motivation as situational, affectively influenced, and continuously fluctuating across time and context. It further underscored that the motivation to move and the motivation to rest are not opposite ends of a single continuum but rather represent interrelated yet distinct systems that jointly regulate spontaneous, moment-to-moment activity (Stults- Kolehmainen et al., 2021). The review also emphasized the value of state-sensitive and ecologically valid assessment tools, such as EMA and accelerometry, for capturing temporal variability in both motivation and behavior in naturalistic contexts (Crosley Lyons et al., 2023; Dunton, 2017). Together, these developments illustrate a paradigmatic shift toward viewing physical activity motivation as a dynamic, affectively charged process that unfolds in real time, bridging theoretical models with methodological innovation.

Chapter 3 evaluated the psychometric properties of the Korean-adapted CRAVE scale (CRAVE-K) among Korean-speaking adults. Following a rigorous, multi-phase translation and cultural adaptation process, the CRAVE-K was administered to 393 participants to assess its factorial validity, internal consistency, and construct validity across both the “Right Now” and “Past Week” forms. Exploratory and confirmatory factor analyses supported the original two-factor structure (Move and Rest) and demonstrated that the 10-item version provided superior model fit compared with the 13-item version. Reliability coefficients were excellent (α = .86– .93) across subscales and timeframes, confirming the internal consistency of the measure. The CRAVE-K demonstrated sound psychometric properties and appears to be a reliable and culturally appropriate instrument for assessing affectively charged motivation states for movement and rest among Korean-speaking adults.

Chapter 4 employed a seven-day EMA design to examine within-person associations among momentary stress, motivation states for physical activity, and accelerometer-measured behavior. Thirty-seven adults completed six smartphone-delivered EMA prompts per day while wearing ActiGraph wGT3X-BT devices in their free-living environments. Multilevel linear mixed-effects models indicated that higher momentary motivation to move was associated with greater engagement in both light-intensity (LPA) and moderate-to-vigorous physical activity (MVPA), as well as lower sedentary time. In contrast, momentary stress was not directly associated with physical activity outcomes. However, higher stress was associated with stronger motivation to rest, suggesting a potential motivational pathway through which stress may influence behavior. Both motivational states and activity patterns exhibited diurnal variation, with motivation to move and physical activity peaking earlier in the day and declining across the evening, while motivation to rest increased later in the day.

Collectively, these studies advance a comprehensive understanding of motivation states for physical activity as a dynamic, context-dependent process shaped by affective and situational factors. By integrating theoretical synthesis, psychometric validation, and real-time behavioral analysis, this dissertation provides an empirically grounded and methodologically rigorous foundation for advancing state-based models of motivation. These findings underscore the importance of capturing momentary experiences to understand and promote physical activity and inform the development of adaptive, precision-based interventions that align with individuals’ motivational readiness and contextual circumstances.