SCIENTISTS have revealed the exercise ‘sweet spot’ you need to hit to live longer.

It’s no secret that working out is a key part of staying healthy for longer – but you don’t need to spend hours at the gym each week to reap the benefits, scientists from the University of Jyväskylä in Finland said.

In fact, moderate levels of activity could be enough to lower your risk of death, they suggested.

Finnish researchers studied the exercise habits of 22,750 twins, following up with them after 15 and 30 years to assess their biological age and risk of mortality.

They split participants up into four groups:

• Sedentary
• Moderately active
• Active
• Highly active

Moderate-movers seemed to reap the most benefits from exercise, with a seven per cent lower risk of death compared to people who didn’t work out.

Though higher levels of exercise were found to lower the risk of mortality in the short-term, it actually brought no additional benefit in the long-term, researchers said.

They found that highly active participants didn’t get any more benefit to their mortality risk – essentially, more is not necessarily better.

Associate professor Elina Sillanpää from the Faculty of Sports and Health Sciences suggested that the idea that ‘being sedentary increases the risk of death’ is incorrect.

Instead, he says: “An underlying pre-disease state can limit physical activity and ultimately lead to death, not the lack of exercise itself.

“This can bias the association between physical activity and mortality in the short term.” 

The twins participating in the study were all born before 1958 and their physical activity was assessed through questionnaires in 1975, 1981 and 1990. 

Over a third (38.8 per cent) of the participants from the sedentary class died during the 30-year follow-up period, compared to 30.8 per cent of the moderately active group, 29 per cent of the active group and 25.4 per cent of the highly active group.

Moderately active and sporty participants had a 16 and 24 per cent lower risk of death compared to the sedentary group.

But after researchers factored in lifestyle-related factors and participants’ body mass index, their risk was only reduced by seven and nine per cent.

“But the moderately active and active classes exhibited lower risks of all-cause mortality compared to the sedentary class and highly active class within all pairs,” researchers wrote in the study published to Nature.

The researchers also investigated whether following the World Health Organization’s physical activity guidelines affects mortality and genetic disease risk.

The guidelines advise adults to do 150 to 300 minutes of moderate or 75 to 150 minutes of vigorous activity weekly.

The study found that meeting these guidelines did not lower people’s risk of death or change their genetic risk.

Even for twins who met the recommended levels of exercise over a 15-year period, there wasn’t a difference in mortality rates compared to their less active twin pair.

Finally, researchers estimated the biological age of participants, looking at how it changed according to exercise levels.

They did this by taking blood samples from participants to get a sense of how fast the cells in their bodies were ageing.

Biological age – the age of our cells – measures how well your body functions and how much wear and tear it’s experienced.

It may be a better indicator than chronological age of how long we’ll will live and be in good health for.

Prof Sillanpää said: “We found that the association between leisure-time physical activity and biological aging was U-shaped.

“Biological ageing was accelerated in those who exercised the least and the most.”

Highly active people were on average, 1.2 years biologically older than the moderately active group and 1.6 years biologically older than the active group.