Adults with stronger and more consistent daily patterns of rest and activity may experience slower biological aging, according to a new study led by researchers at the Johns Hopkins Bloomberg School of Public Health. The researchers found that individuals with clearer distinctions between daytime activity and nighttime rest, less fragmented daily rhythms, and more stable day-to-day patterns showed signs of being biologically younger based on blood-test measures of physiological aging.
The study analyzed data from 207 adults participating in the long-running Baltimore Epidemiologic Catchment Area cohort study. Participants wore wrist-based actigraphy devices for approximately seven consecutive days to measure their rest-activity rhythms. Researchers then compared these data with four established epigenetic “clocks” derived from blood samples—Horvath, Hannum, PhenoAge, and GrimAge—which estimate physiological aging based on DNA-related biological markers.
The findings showed that stronger and more regular rest-activity rhythms were significantly associated with lower physiological age scores, particularly on the GrimAge and PhenoAge measures. These relationships remained significant after accounting for chronological age and other factors such as sex, education, and health conditions. The associations appeared stronger among women and white participants.
The study’s co-senior author, Adam Spira, said the findings suggest that rest-activity rhythms could become useful indicators of physiological aging and may eventually serve as targets for interventions aimed at slowing the aging process. Co-senior author Brion Maher noted that the results may actually underestimate the true association because the study involved older adults who had survived and remained healthy enough to participate. Lead author Chunyu Liu emphasized the need for future longitudinal studies to determine whether disrupted rhythms contribute to accelerated aging or result from it.
Scientists have increasingly used wearable devices to monitor rest-activity rhythms in everyday life. Previous research has linked weaker and more fragmented rhythms to brain atrophy, mild cognitive impairment, dementia, psychiatric disorders, and certain cancers. Although rest-activity rhythms naturally weaken with age, chronological age alone may not fully reflect biological decline, which can also be influenced by factors such as inflammation, high blood sugar, and smoking.
The researchers hope future studies and clinical trials will determine whether strengthening and stabilizing daily rest-activity rhythms can help slow physiological aging. They also anticipate that wearable technologies may eventually allow older adults and clinicians to monitor biological aging and related health risks more easily in routine daily life.
More information: Chunyu Liu et al, Twenty-Four–Hour Rest-Activity Rhythms and Epigenetic Age Acceleration in Middle-Aged and Older Adults, JAMA Network Open. DOI: 10.1001/jamanetworkopen.2026.11474
Journal information: JAMA Network Open Provided by Johns Hopkins Bloomberg School of Public Health
