Researchers claim that the mean difference in leukocyte telomere length between the most active subjects, performing 199 minutes of physical activity per week, and least active subjects, performing 16 minutes of activity per week, was 200 nucleotides.
What this means is that the most active subjects had telomeres the same length as sedentary individuals up to 10 years younger, on average. Stress has also been linked to telomere length. The study authors suggested exercise may reduce stress and its effect on telomeres and the aging process.
The authors wrote that "Our results underscore the vital importance of the U.S. guidelines recommendation of 30 minutes of moderate exercise 5 days a week. Adults who partake in regular physical activity are biologically younger than sedentary individuals. This conclusion provides a powerful message that could be used by clinicians to promote the potential anti-aging effect of regular exercise.