New research – published the the journal Neurology – found that middle age women with high physical fitness were 90 percent less likely to develop dementia later on down the track, compared to those who were moderately fit. Dementia is the term used to describe a range of neurological conditions in which brain function declines resulting in impaired memory, thinking and behaviour. The biggest risk factor for developing dementia is increasing age.
In the study, researchers analysed the peak cardiovascular capacity of 191 middle age women as they completed a bicycle exercise until exhausted. Of the group, 40 participants met the criteria for a high fitness level with a capacity of 120 watts or more. 92 of the women were of medium fitness level and 59 were of low fitness level, defined as a peak workload of 80 watts or less or the inability to complete the test because of health issues.
These women were then tested for dementia six times over the following four decades. A total of 44 women in the group developed the disease, five percent of the highly fit participants, 25 percent of the moderately fit women and 32 percent of those with a low fitness level.
The super fit women with dementia developed the disease an average of 11 years later than women who were moderately fit.
"These findings are exciting because it's possible that improving people's cardiovascular fitness in middle age could delay or even prevent them from developing dementia," said study author Helena Hörder.
"However, this study does not show cause and effect between cardiovascular fitness and dementia, it only shows an association. More research is needed to see if improved fitness could have a positive effect on the risk of dementia and also to look at when during a lifetime a high fitness level is most important."