One Day, 1,440 Minutes: New Model Maps How Sleep, Sitting and Movement Shape Health Together

Every day hands each of us the same budget: 1,440 minutes. How we spend them—sleeping, sitting, or moving—may be one of the most powerful levers on our physical and mental health, yet most theories of health behavior treat these activities as if they were independent choices. A new theoretical framework published in the Journal of Activity, Sedentary and Sleep Behaviors argues that this fragmented view is holding the field back, and it proposes a radically integrated alternative. The 24-hour cognitive-affective physical behavior model, developed by Marco Giurgiu and Ulrich W. Ebner-Priemer of the Karlsruhe Institute of Technology and the Central Institute of Mental Health in Mannheim, places the entire composition of a person’s day at the center of a network of psychological and physiological pathways, each with a precisely defined timescale.

The authors begin from an uncomfortable observation: decades of behavior change research, from the theory of planned behavior to self-determination theory and socioecological models, explain only a modest proportion of the differences in physical behavior between and within individuals. People are notoriously inconsistent—one week they jog daily, the next they barely leave the sofa. The researchers attribute this weak predictive power to three structural shortcomings in existing models. First, most frameworks focus either on the short-term determinants that drive behavior or on the long-term health consequences that flow from it, rarely both. Second, they overlook the fact that consequences can loop back and become determinants: fitness gained through months of exercise also shapes how active you feel like being tomorrow. Third, and most fundamentally, they ignore the arithmetic of the day itself.

That arithmetic is unforgiving. Sleep, sedentary behavior, and physical activity are locked together within the fixed 1,440 minutes available, so every additional minute spent in one behavior must come at the expense of another. A person who adds thirty minutes of morning running necessarily removes thirty minutes from sleep, sitting, or some other activity. Traditional single-behavior studies, which examine physical activity in isolation, cannot capture these trade-offs. The new model builds on earlier 24-hour frameworks—including Pedišić’s Activity Balance Model, the Framework for Viable Integrative Research in Time-Use Epidemiology, and Rosenberger and colleagues’ 24-hour Activity Cycle—but goes further by explicitly embedding the full daily composition within a dual-process psychological architecture and a health-outcome architecture, connected by eight distinct pathways labeled A through H.

The left side of the model, adapted from the neurocognitive affect-related model, describes how the brain’s moment-to-moment machinery shapes what we do with our time. Its central constructs are affective states and executive functions. Following the work of Duncan and Barrett, the authors treat affect as a neurophysiological state defined by two dimensions: valence, the pleasantness or unpleasantness of a feeling, and energetic arousal, the level of activation. Executive functions, as defined by Diamond, encompass inhibition control, working memory, and cognitive flexibility—the mental capacities that let us plan, resist temptation, and stay focused on long-term goals despite distractions. The model proposes that optimal daily compositions of sleep, sitting, and activity can enhance these executive functions, which in turn foster more positive affective responses, which then facilitate healthier future behavior compositions.

Crucially, these pathways are reciprocal. Pathway A suggests that executive-function-based cognition shapes the emotional responses induced by exercise or prolonged sitting; pathway B connects those emotional responses to the future balance of daily behaviors, since affective reactions during a workout predict whether a person returns to exercise. Pathways C and D close the loop: cognitive preparation such as time management and goal setting influences the day’s activity composition, while the composition itself—regular exercise, adequate sleep—feeds back to improve cognitive function. The authors also acknowledge bidirectionality in the reverse direction, noting that physical behavior can predict momentary affect and that momentary affect can predict executive function performance, making the entire left side of the model a dynamic, self-modifying system rather than a one-way causal chain.

The right side of the model, adapted from the health model of Bouchard, Blair, and Haskell, traces the physiological consequences. Here the claim is that an optimal daily composition improves health-related fitness markers such as cardiorespiratory fitness (pathway E), which then improves the state of physical and mental health, from well-being to mortality risk (pathway F). The evidence base for these links is substantial. A systematic review of fifty-six isotemporal substitution studies concluded that reallocating time between sleep, sedentary behavior, light-to-moderate activity, and moderate-to-vigorous activity is associated with numerous health outcomes. A meta-analysis further showed that short sleep is significantly linked to mortality, diabetes, cardiovascular disease, coronary heart disease, and obesity. These pathways, too, can run backward: fitness markers predict individual behaviors, health status predicts fitness, and illness or injury—captured by pathway H—can abruptly reshape the whole day, as anyone with a broken leg who suddenly spends far more time sleeping and sitting can attest.

What distinguishes this framework from its predecessors is its insistence on temporal resolution. The authors divide the eight pathways into short-term dynamics operating within days, medium-term associations across weeks and months, long-term effects over years, and mixed pathways spanning days to years. Affective states fluctuate hour to hour and even minute to minute, so pathways A, B, and C demand high-granularity, real-world data. The state-of-the-art tool here is ambulatory assessment: smartphone-based electronic diaries capturing real-time self-reports, paired with wearable sensors measuring the full 24-hour behavior composition objectively and repeatedly. This approach preserves ecological validity and avoids the retrospective biases that plague questionnaire studies. By contrast, the fitness pathway E requires weeks or months of observation, ideally through randomized interventions with repeated and follow-up measurements, while the health pathways F and G unfold over years and call for long-term cohort studies—one 18-year community study found that habitual physical activity related positively to both fitness and health status decades later.

The model also arrives at a moment when the statistical machinery for 24-hour research has matured. Compositional data analysis treats sleep, sedentary time, and activity as parts of a finite whole, analyzing them relative to one another rather than as independent variables, and the compositional isotemporal substitution method estimates what happens to a health outcome when a fixed block of time is shifted from one behavior to another. The empirical payoff is already visible. In an analysis of six cross-sectional studies covering 15,253 participants, moderate-to-vigorous physical activity showed the strongest and most time-efficient protective associations with cardiometabolic outcomes, while sedentary behavior was the only behavior with clearly adverse associations regardless of duration. The Maastricht Study, with 2,388 participants, found that less sitting and more standing, physical activity, and sleep were associated with better cardiometabolic health and glycaemic control. Device-based measurement via wearables now makes it possible to capture every facet of the daily composition with time-stamped precision, and the model’s components can be refined as needed—splitting activity into standing, light, and vigorous categories, or sleep into REM and non-REM stages, or even distinguishing outdoor from indoor activity.

The long-term ambition is strikingly concrete: to identify the optimal balance of 24-hour behaviors that maximizes health benefits and promotes longevity and well-being. Tremblay and colleagues anticipate that the 24-hour approach will eventually underpin individualized, precision movement guidelines tailored to personal characteristics and circumstances—several countries and the World Health Organization already issue integrated 24-hour movement guidelines. The authors are careful to note that the relationships in their model are shaped by genetic predispositions, social and physical environments, and individual circumstances, which may moderate, mediate, or confound the pathways, so generalization demands caution. But by combining behavioral, affective, and health determinants and consequences in a single flexible framework, and by specifying exactly which timescale each hypothesis should be tested on, the 24-hour cognitive-affective physical behavior model gives researchers something previous theories did not: a shared map of the entire day, drawn to scale, with the clock built in.

Subject of Research: The 24-hour cognitive-affective physical behavior model: a theoretical framework for studying determinants and health consequences of physical activity, sedentary behavior, and sleep

Article Title: The 24-hour cognitive-affective physical behavior model: a theoretical framework for studying determinants and health consequences of physical activity, sedentary behavior, and sleep

Article References: Giurgiu, M., & Ebner-Priemer, U. W. (2025). The 24-hour cognitive-affective physical behavior model: a theoretical framework for studying determinants and health consequences of physical activity, sedentary behavior, and sleep. Journal of Activity, Sedentary and Sleep Behaviors, 4(1), Article 6. https://doi.org/10.1186/s44167-025-00077-9

Image Credits: AI Generated

DOI: 10.1186/s44167-025-00077-9

Keywords: hour, cognitive-affective, physical, behavior, model, theoretical, framework, studying, determinants, health, consequences, activity