Aerobic + Strength Exercise Doesn't Slow Cognitive Decline


Due to the widespread belief that exercise is beneficial for delaying dementia, a team of United Kingdom researchers conducted a study to assess for themselves the effect of physical activity on the symptoms of dementia.

The sessions included 20 minutes on a fixed cycle and lifting weights while getting out of a chair.

The authors wrote: "People with mild to moderate dementia can engage and comply with moderate to high intensity aerobic and strengthening exercise and improve physical fitness".

The researchers said their exercise programme "does not slow cognitive decline in people with mild to moderate dementia". Of these, 329 were randomized to an aerobic and strength exercise program, involving usual care plus 4 months of supervised exercise and support for ongoing physical activity, and 165 were randomized to usual care.

Although several recent studies reported that exercise may improve memory and slow down mental decline, there have also been studies with conflicting results.

The participants in both groups had their cognitive abilities and physical fitness assessed at the start of the study and then six and 12 months later.

"These benefits do not, however, translate into improvements in cognitive impairment, activities in daily living, behaviour, or health-related quality of life".

More than a third of the people invited to take part in the study declined, and 60% of the participants were men, which is unusual in dementia studies because more women than men have the condition. Compliance with the exercise program was good. The complier average causal effect estimate for the primary outcome was -2.0 (95% CI -3.87 to -0.22), indicating worse cognitive impairment in people who attended more exercise sessions. And the number of people who declined to participate in the study was high; more men than women participated, even though dementia is more common in women in western Europe.

People taking part in RCTs usually do not know whether they're in the treatment or control group, but this was impossible to hide for an exercise study.

I want to encourage your readers to unite against dementia and take action to fix dementia care in Greater Manchester.

It was funded by the National Institute of Health Research and published in the peer-reviewed British Medical Journal on an open-access basis, so it's free to read online.

An Alzheimer's Society investigation has discovered that 50,000 people with dementia were admitted to A&E across the country in the previous year, because inadequate social care is leaving them unprotected from falls and infections. We followed people up for much longer than most studies do.

These recommendations were made by the NHS, which added, "there's good evidence that a healthy lifestyle can help reduce your risk of developing dementia when you're older".