If you have been meaning to add more exercise to your daily routine, you may want to start sooner rather than later.

A 2018 study has found that a lifetime of regular exercise and activity can slow down the aging process.

Researchers at Britain’s University of Birmingham and King's College London say that getting older should not necessarily mean becoming more weak or sick. Their research shows that a commitment to a life of movement and exercise may help us live not only longer, but also healthier.

For their study, the researchers looked at two groups.

The first group was made up of 125 non-professional cyclists between the ages of 55 to 79. This group included 84 healthy men and 41 healthy women. We will call this group the “cyclists.”

Researchers then found 130 people to make up a second group. Within this group, 75 people were aged 57 to 80. The other 55 were between the ages of 20 and 36. The people in this group were also healthy, but they did not exercise regularly. We will call this group the “non-exercisers.”

Smokers, heavy drinkers of alcohol and people with other health issues were not included in the study.

Then, researchers gave both groups a series of tests. They tested their muscle mass, muscular strength, percentage of body fat, cholesterol levels and the strength of their immune systems. And male participants had their testosterone levels checked.

Then the researchers compared the results of the two groups.

Results showed that the cyclists did not experience body changes usually equated with a normal aging process. For example, they did not lose muscle mass or strength. Also, their body fat and cholesterol levels did not increase with age.

The male cyclists’ testosterone levels had also remained high. Researchers say this may mean that they avoided at least one major symptom of male menopause.

The researchers also found something they had not expected. The study showed that the immune systems of the cyclists did not seem to age either. For this, they looked at an organ called the thymus. The thymus makes immune cells called T-cells.

The University of Arizona’s biology department explains on its website that T-cells are a type of white blood cell and are made in our bone marrow.

As the article says: “There are two types of T-cells in your body: Helper T-cells and Killer T-cells. Killer T-cells do the work of destroying the infected cells. The Helper T-cells coordinate the attack.”

Starting at about the age of 20, the thymus of most people starts to get smaller. It also starts to make fewer T-cells.

However, in this study, the T-cell production by the thymuses of the cyclists had not slowed down with age. They were making as many T-cells as those of a young person.

Janet Lord is director of the Institute of Inflammation and Ageing at the University of Birmingham. In a press statement, she offers the words of Hippocrates, often called the “father of medicine.”

She writes: "Hippocrates in 400 BC said that exercise is man's best medicine, but his message has been lost over time and we are an increasingly sedentary society.”

Professor Stephen Harridge is director of the Centre of Human & Aerospace Physiological Sciences at King's College London. He addressed the common question of what came first -- the chicken or the egg? In this case, the question became, “Which came first -- the healthy behavior or the good health?"

When talking about the findings of the study, he said “the cyclists do not exercise because they are healthy, but that they are healthy because they have been exercising" for such a large portion of their lives.

The researchers advise us all to find an exercise that we like and to make physical activity a priority in our lives.

They published their findings in Aging Cell. The study is part of ongoing research by the two universities.