How you structure your day, when you move, when you rest, and how consistently you do both, may have more bearing on how your body ages than previously understood. A study published in JAMA Network Open found that middle-aged and older adults with stronger and more regular rest-activity rhythms showed lower biological aging scores on two established epigenetic measures. The findings suggest that daily behavioral patterns are not just a byproduct of good health. They may be actively shaping it.
Biological age versus chronological age
Chronological age counts years. Biological age measures how well the body is actually functioning. The two do not always match. Lifestyle factors including diet, physical activity, and sleep quality can push biological age below or above the number on a birth certificate.
Researchers increasingly use epigenetic clocks to estimate biological age. These tools track chemical modifications to DNA that accumulate over time and correlate with aging-related health risks. When a person’s biological age runs ahead of their chronological age, it can signal elevated risk for age-related disease. The two epigenetic clocks used in this study, GrimAge and PhenoAge, are designed specifically to capture those health and mortality-linked aging signals.
How the study worked
The study drew on 207 participants from the Baltimore Epidemiologic Catchment Area cohort, with an average age of 68. Each participant wore a wrist actigraphy device for one week. The device tracked movement, stillness, sleep, and sedentary time continuously, building a detailed picture of each person’s daily rhythm.
Participants who showed cleaner separations between daytime activity and nighttime rest, and whose routines were less fragmented day to day, consistently scored lower on both biological age measures. The associations held up after researchers controlled for chronological age, sex, education level, and existing health conditions.
Co-senior author Brion Maher, a researcher at Johns Hopkins, noted that the strength of those associations aligned with what the newer epigenetic clocks are built to detect. Because rest-activity patterns are so closely tied to overall physiological health, their relationship to aging-sensitive biological markers is not incidental.
Rest-activity rhythms and the aging connection
The mechanism linking daily rhythms to biological aging runs through the circadian system, the body’s internal clock, which coordinates everything from hormone release to immune function to cellular repair. When activity and rest patterns are fragmented or inconsistent, that coordination breaks down. Over time, the disruption leaves measurable traces at the epigenetic level.
What makes this study notable is not the idea that sleep and movement matter. That part is well established. What it adds is a more precise picture of how the structure of daily rhythms, their regularity and their contrast between active and restful periods, maps onto biological aging in a population that is already in midlife or beyond.
What this means for interventions
Lead author Chunyu Liu pointed to wearable technology as a practical tool for identifying people whose daily patterns are disrupted enough to warrant earlier intervention. A week of actigraphy data, collected passively through a wrist device, can flag irregular rhythms before they translate into clinical symptoms. That window for intervention is part of what makes the findings actionable.
The researchers suggest that lifestyle adjustments aimed at reinforcing daily rhythms may function as a form of biological age management. Keeping a consistent sleep and wake schedule, getting natural light exposure during the day, building regular physical activity into the routine, and avoiding prolonged stretches of inactivity all support the kind of structured daily pattern the study associates with slower aging. Managing caffeine and alcohol intake, keeping meal times consistent, and limiting irregular napping can further stabilize the body’s internal clock.
What the findings add to aging research
The study is not without limitations. One week of actigraphy captures a snapshot rather than a longitudinal picture, and the sample size is modest. But as epigenetic research tools become more refined, the relationship between daily behavioral patterns and biological aging is becoming harder to dismiss as correlation.
The broader implication is that some of the most accessible levers for influencing how the body ages are behavioral. They do not require a prescription. They require consistency.
