The older we get, the more we're entitled to slow down. Kick back, we're told, relax and revel in a well-earned sedate retirement.

But two physical activity experts believe nothing could be further from the truth. Far from becoming less active, the over-60s should exercise as much as possible to help protect them from disease, isolation and a loss of independence.

"We are mis-sold a dogma in society that as we get older, we can start to take it easier. Let me just confirm that that is absolutely untrue. In fact, what we know is that as we get older, we need to work harder," said Greg Whyte, a former Olympic modern pentathlete and director of performance at the Centre for Health and Human Performance in London.

World Health Organization guidelines recommend exercising for 150 minutes at moderate intensity a week for over-65s. This would include activities such as a brisk walk to avoid conditions such as sarcopenia, in which muscles in both men and women degenerate over time through inactivity. 

Speaking at the recent CogX summit on emerging technologies, Whyte said slowing muscle wastage, or even stopping it entirely, is crucial for maintaining a good quality of life for the elderly.

"That is incredibly important because it underpins power and strength, which underpin our ability to stay independent. So, independence is critically linked to muscle mass, which also underpins aerobic capacity," said Whyte.

It's about more than walking to the shops, too. Protection from disease also rises significantly.

"The greatest gains are actually made from those who move from inactivity to some activity. Physical activity is linked to a reduction of a whole host of 'comorbidities,' including cancer, type 2 diabetes, heart disease, cardiovascular disease, peripheral vascular disease and so on.

"Your target is to be more active, more often. And what you are trying to do is move that position from sedentary through to 150 minutes a week."

Exercise helps speed up a process called "autophagy," which is the body's way of cleaning out damaged protein cells to regenerate them as newer, healthier ones.

"Autophagy is where those little proteins congregate," said Jack Kreindler, founder and medical director of the Centre for Health and Human Performance. 

"Most of the stuff in your body's cells is made of protein, but those proteins get misfolded over time and you reuse, you recirculate them, except if you're eating too much protein."

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Autophagy occurs when the body is in the process of what scientists call fasting or mini starvation. The more active a person's lifestyle, the greater the protection from health complications.

"One of the issues with degenerative diseases or cancers is that you accumulate lots of errors inside your cells rather than flush them out. You continue to have those things hanging around," said Kreindler, who was also speaking at the CogX event.

In a world still coming to terms with the COVID-19 pandemic, a sedentary lifestyle is not just the stereotypical preserve of the elderly, as many struggle to find the motivation to exercise with gyms, clubs and contact sport postponed during lockdown.

Forcing the regenerative autophagy process through physical activity is therefore vital.

"Exercise burns an excess of energy and by burning an excess of energy, you go into an equivalent state where there are times in the day or times of the week where you are fasting," said Kreindler.

"Any exercise where you're exceeding the number of calories that are freely available to you in your system is good."

You may not be able to put your feet up quite as much as you wanted in your dotage (or coronavirus-induced laziness) but just a bit of exercise will protect you from disease and make old age a much more enjoyable time.

Check out The Pandemic Playbook, CGTN Europe's major investigation into the lessons learned from COVID-19