After 12 months, the participants were assessed according to the commonly used Alzheimer's disease assessment score (ADAS-cog), which measures cognitive and rationalizing abilities, as well as outcomes such as their quality of life and number of falls.
According to the World Health Organisation, about 50 million people worldwide suffer from the dementia, including Alzheimer's Disease as well - the most common form accounting for about two-thirds of the cases. They said they can not exclude the possibility that exercise may have made dementia worse, although the differences in decline were small.
The authors said the study had shown people with mild to moderate dementia could engage in moderate to high-intensity exercise to improve their physical fitness.
Although the results may appear concerning, the study authors said they could be down to the time spent exercising being too short to have a positive return, or participants or carers being aware of which group they were in.
People with early dementia were able to follow an exercise regimen and boost their physical fitness. The team assigned 329 people to partake in a four-month aerobic and strength exercise program. Those taking part in the exercise programme had their physical fitness measured at the start of the programme and again after 6 weeks.
Contributing activity included moderate to high intensity aerobic and strength exercise training. However, the average difference was small and clinical relevance was uncertain.
However, while she discouraged adding moderate to intense exercise to their fitness routine, she advised dementia patients should continue to gentler activities such as walking and swimming.
"These benefits do not, however, translate into improvements in cognitive impairment, activities in daily living, behaviour, or health-related quality of life". Also, both the participants and their family caregivers knew which group they were in, a factor that could have affected the results. It comes after a number of small studies looking at exercise for people with dementia had conflicting results.
Still, this study is the most robust one to date to investigate the effect of exercise on dementia.
I want to encourage your readers to unite against dementia and take action to fix dementia care in Greater Manchester. Lamb commented that dementia is a complicated issue to tackle.
It's important to note this does not change what we know about exercise's ability to protect against dementia.
People with dementia are now forced to rely on services so starved of funding that they're unable to protect them from harm and the doors of A&E, let alone provide specialist care and support.
FMI: You can read the study in full on the BMJ's website.