Researchers from the University of Jyväskylä in Finland reported that very high levels of physical activity may accelerate markers of biological aging. The findings were published on the medRxiv platform and have sparked discussions about how exercise intensity influences the aging process over a lifetime.
The study followed a large cohort of volunteers, involving nearly 11,000 twin pairs aged between 18 and 50 years at the start, with observations spanning from 1975 to 2020. Before the monitoring began, investigators gathered detailed information about each participant’s health status and their typical activity patterns. Participants were categorized into four groups based on activity levels: sedentary, moderately active, active, and very active, with 13.4%, 36.7%, 38.7%, and 11.2% of the group in each respective category. This structure allowed researchers to compare long term health trajectories across different lifestyle profiles and to explore how genetic and environmental factors might interact with physical activity to influence aging.
Crucially, the researchers did not specify exact thresholds for the amount of time spent exercising to place someone in a given category. They also collected blood samples in order to estimate biological age, a measure that reflects the wear and tear on bodily organs and systems. The team calculated biological age by examining changes in DNA methylation patterns and other molecular indicators that signal aging processes over time. These biomarkers provide insight into how the body ages at the cellular level, beyond what is visible in a simple calendar age. The aim was to determine whether different levels of activity correlate with a slower or faster pace of aging, as captured by these molecular signals, across a diverse population of twins. The work was conducted in a controlled framework designed to account for shared genetics and early life conditions common to twin pairs, helping to isolate the potential impact of physical activity on aging markers.
Results showed that volunteers in the second, third, and fourth activity groups displayed a lower likelihood of aging faster compared with sedentary peers. Specifically, the data suggested a 15 to 23 percent reduction in the probability of experiencing accelerated aging for those who were moderately to very active. When researchers adjusted for weight and lifestyle-related factors such as smoking, alcohol use, and other habits, highly active individuals still showed about a 7 percent lower risk of adverse aging outcomes relative to those who were inactive. In addition, those who put substantial effort into physical exercise appeared to be 1.8 and 1.3 years biologically older than their more active peers within the highest and average activity categories, respectively. These offsets emerged after careful statistical modeling that tried to separate the genuine effects of exercise from other contributors to aging. Overall, the study points to a nuanced link: regular physical activity carries meaningful health benefits, but extremely high levels may introduce complexities that influence biological aging in ways that warrant further exploration.
Even with these nuanced findings, the broader takeaway aligns with established public health guidance. Regular movement, even at moderate intensities, supports cardiovascular health, metabolic regulation, and functional capacity as people age. The study underscores the importance of balancing activity with other health factors and highlights the value of considering genetic background and long term lifestyle patterns when evaluating aging trajectories. It is important to interpret the results in the context of population-level data and repeated measurements across decades, acknowledging that individual experiences can vary widely based on diet, sleep, stress, and environmental exposures. The researchers emphasize that these are associations observed in a large and well-characterized twin cohort, and they call for additional studies to confirm mechanisms and to determine practical recommendations for different age groups and activity levels, while keeping safety and overall well-being in focus.
The discussion around physical activity and aging remains active in scientific circles. Acknowledging potential limits of extreme exercise does not negate the well documented benefits of staying active for most people. Instead, it invites a balanced approach where exercise is part of a broader lifestyle strategy that supports healthy aging, including nutritious eating, adequate rest, and ongoing medical surveillance. In the end, the core message is that movement matters for longevity, but the relationship between intensity, duration, and aging markers is complex and continues to be clarified by ongoing research. For now, the emphasis remains on sustainable activity that fits an individual’s health status and life circumstances, paired with regular medical guidance to monitor aging-related biomarkers over time.