Physically active people are biologically younger than people who have a sedentary lifestyle, a British study revealed.

Scientists from the King’s College London gathered their information from an experiment involving 2,401 white twins. They found key pieces of DNA called telomeres shortened more quickly in inactive people. It is believed that could signify faster cellular ageing. As people age, their telomeres become shorter, leaving cells more susceptible to damage and death. People who were active had longer telomeres than those of the same age that were sedentary.

“A sedentary lifestyle increases the propensity to aging-related diseases and premature death. Inactivity may diminish life expectancy not only by predisposing to aging-related diseases, but also because it may influence the aging process itself," study author Lynn F. Cherkas, of King's College London, said in a prepared statement.

People who have an active lifestyle seem to have lower rates of cardiovascular disease, type 2 diabetes and cancer. According to the new research, inactivity is also connected to a speed of the ageing process itself.

“Such a relationship between leukocyte telomere length and physical activity remained significant after adjustment for body-mass index, smoking, socioeconomic status and physical activity at work. The mean difference in leukocyte telomere length between the most active [who performed an average of 199 minutes of physical activity per week] and least active [16 minutes of physical activity per week] subjects was 200 nucleotides, which means that the most active subjects had telomeres the same length as sedentary individuals up to 10 years younger, on average,” the authors wrote in their study.

The researchers also suspected stress to have an effect on the length of the telomere and concluded that people with greater physical exercise experience reduction in stress level.

“These data suggest that the act of exercising may actually protect the body against the aging process,” said Tim D. Spector, a professor of genetic epidemiology at King's College in London

The researchers said they hoped doctors could use the findings to encourage people to exercise.

“Hopefully, when clinicians are advising patients, this could be another reason to offer. It may slow down the aging process and people may actually look and feel younger, which we know would be a good thing for most of the population,” Spector said.

However, more research is needed to confirm a direct link between physical activity and aging, the researchers said.

The study was published in the Journal of the American Medical Association’s Archives of Internal Medicine.