Keeping active throughout life could help keep the body younger and healthier as we age, according to new research in the United Kingdom.
Carried out by researchers at the University of Birmingham and King's College London, the study set out to look at whether a lifetime of exercise had slowed down aging in a group of older adult participants.
The researchers recruited 125 male and female healthy amateur cyclists, who were aged 55 to 79 and had been cycling for nearly all of their adult lives.
The participants provided blood samples and muscle biopsy samples, which were then compared to a group of healthy adults who did not take part in regular physical activity.
This group consisted of 55 young adults aged 20 to 36 and 75 older adults aged 57 to 80.
Results showed that a loss of muscle mass and strength, which is often believed to be normal part of the aging process, did not occur in the cyclists.
In addition, their body fat and cholesterol levels also had not increased with age.
The men's testosterone levels had also remained high, rather than declined with age, suggesting that they may have avoided most of the "male menopause".
Even more surprisingly, the researchers also found that exercise appeared to have an anti-aging effect on the immune systems of the cyclists, as well as their muscles.
An organ called the thymus, which makes immune cells called T cells, starts to shrink from the age of 20 and makes less T cells; however the team found that in this study, the cyclists' thymuses were making as many T cells as those of a young person.
Commenting on the findings, Dr. Niharika Arora Duggal from the University of Birmingham, said, "We hope these findings prevent the danger that, as a society, we accept that old age and disease are normal bedfellows and that the third age of man is something to be endured and not enjoyed."
Professor Stephen Harridge, director of the Centre of Human & Aerospace Physiological Sciences at King's College London, also added, "The findings emphasise the fact that the cyclists do not exercise because they are healthy, but that they are healthy because they have been exercising for such a large proportion of their lives. Their bodies have been allowed to age optimally, free from the problems usually caused by inactivity. Remove the activity and their health would likely deteriorate."
"Find an exercise that you enjoy in whatever environment that suits you and make a habit of physical activity. You will reap the rewards in later life by enjoying an independent and productive old age," he said.
The findings can be found detailed in two papers published online in the journal Aging Cell.