Experts pinpoint specific age when ramping up exercise could help prevent dementia

Daily Mail​

02-05-2025

Upping your exercise quota when you hit middle age really could help stave off Alzheimer's disease in later life, researchers have discovered.
Spanish scientists, who tracked more than 300 adults, found those who increased their activity levels to around two and a half hours a week, between the ages of 45 and 65, were less prone to one toxic protein, amyloid, spreading in the brain.
Significant clumps of this protein, as well as another — tau — can form plaques and tangles.
This is thought to be behind the symptoms of Alzheimer's, the leading cause of dementia.
The team, from the Barcelona Institute for Global Health, also said those who exercised more were more likely to preserve volume in the part of the brain linked to thinking and memory.
Dr Eider Arenaza-Urquijo, an expert in brain ageing and Alzheimer's disease and study lead author, said: 'These findings reinforce the importance of promoting physical activity in middle age as a public health strategy for Alzheimer's prevention.
'Interventions aimed at promoting increased physical activity could be key to reducing the incidence of the disease in the future.'
Dr Müge Akıncı, an expert in Alzheimer's risk factors and study co author, added: 'Even those who did less physical activity than recommended had greater cortical thickness than sedentary people, suggesting that any amount of exercise, no matter how minimal, has health benefits.'
Experts have warned for years that being stationary for too much of the day raises the risk of numerous health problems including weight gain, type 2 diabetes, cancer and even an early grave.
In the study, researchers tracked 337 adults who underwent activity questionnaires and neuroimaging tests.
Over a follow-up of four years they discovered participants who upped their exercise to meet both the World Health Organisation (WHO) and NHS recommendations showed less amyloid accumulation in brain scans compared to those who were sedentary or reduced their activity.
The NHS recommends adults get at least 150 minutes of moderate-intensity exercise a week — or 75 minutes of vigorous exercise.
The research, published in the journal Alzheimer's & Dementia, also suggested that those who were inactive but then started to exercise especially benefitted.
Scientists also found that the brains of participants who exercised more were thicker in the parts responsible for memory — the medial temporal area.
It has been estimated that 13 per cent of all Alzheimer's cases could be linked to physical inactivity.
Around 900,000 Britons are currently thought to have the memory-robbing disorder. But University College London scientists estimate this will rise to 1.7 million within two decades as people live longer. It marks a 40 per cent uptick on the previous forecast in 2017
Dr Sarah-Naomi James, a neuroepidemiologist at University College London, who was not involved in the study, said: 'The research is in line with a whole body of evidence that generally shows that being sedentary and inactive is bad for brain health.
But exercise later in life still might reduce the risk for Alzheimer's, she noted.
'In my work we show that starting to be active for the first time in your sixties showed some beneficial effects.'
Dr Lucy Devendra, head of research at the charity Alzheimer's Society, also said: 'We know that staying active later in life can still bring important benefits, from mood and sleep to mobility.'
She added: 'We can't say for certain that exercise caused the brain changes. Changing one behaviour, like exercise, won't guarantee prevention but is still worthwhile for overall health.'
It comes as a landmark study last year also suggested almost half of all Alzheimer's cases could be prevented by tackling 14 lifestyle factors.
To reduce dementia risk throughout life, the commission also made 13 recommendations for both people and governments.
These include making hearing aids available for all those who need it, reducing harmful noise exposure, and increased detection and treatment access for high cholesterol among the over-40s.
Experts claimed the study, published in the prestigious journal The Lancet, provided more hope than 'ever before' that the memory-robbing disorder that blights the lives of millions can be prevented.
Alzheimer's Disease is the most common form of dementia and affects 982,000 people in the UK.
Alzheimer's Research UK analysis found 74,261 people died from dementia in 2022 compared with 69,178 a year earlier, making it the country's biggest killer.
Sedentary lifestyles in the UK, with Brits spending their workhours deskbound, then sitting in a train or car on their way home to sit down in front of the TV, have been estimated to kill thousands each year.
One 2019 estimate put the annual death toll at 70,000 people a year with the health issues caused costing the NHS £700million each year to treat.
The WHO puts the annual global death toll from physical inactivity at around 2million per year, making it in the running to be among the top 10 leading causes of global death and disability.
To stay healthy, adults aged 19 to 64 should try to be active daily and should do:
at least 150 minutes of moderate aerobic activity such as cycling or brisk walking every week and
strength exercises on 2 or more days a week that work all the major muscles (legs, hips, back, abdomen, chest, shoulders and arms)
Or:
75 minutes of vigorous aerobic activity such as running or a game of singles tennis every week and
strength exercises on 2 or more days a week that work all the major muscles (legs, hips, back, abdomen, chest, shoulders and arms)
Or:
a mix of moderate and vigorous aerobic activity every week – for example, 2 x 30-minute runs plus 30 minutes of brisk walking equates to 150 minutes of moderate aerobic activity and
strength exercises on 2 or more days a week that work all the major muscles (legs, hips, back, abdomen, chest, shoulders and arms)
A good rule is that 1 minute of vigorous activity provides the same health benefits as 2 minutes of moderate activity.
One way to do your recommended 150 minutes of weekly physical activity is to do 30 minutes on 5 days every week.