Abstract
Health behavior research has generated extensive knowledge about motivational and volitional determinants of behavior, yet it often treats behavior as an aggregate outcome rather than specifying the unit through which action is cognitively organized and enacted. This paper introduces episodic health behavior as health-relevant action represented and regulated as discrete behavioral episodes. Drawing on research in event cognition, we define behavioral episodes as temporally bounded and contextually situated units of action with specific initiation conditions, unfolding trajectories, and end states that can be prospectively anticipated, enacted, and retrospectively experienced. We argue that this framework addresses a structural mismatch between aggregate measurement and the episodic organization of behavioral enactment. The episodic perspective reframes core phenomena in health psychology: the intention-behavior gap reflects temporal and contextual misalignment between momentary intentions and behavioral opportunities, planning specifies actionable episode representations, habitualization increases efficiency in the initiation of recurrent episodes, and behavior change can be understood as a transformation in the frequency, regularity, and stability of episodic chains. The framework provides a theoretical rationale for intensive longitudinal designs, event-contingent assessment, within-episode measurement, and phase-sensitive interventions, particularly for recurrent health behaviors. It also identifies boundary conditions concerning participant burden, measurement reactivity, missing data, and analytic complexity.