Women who run, take spin classes or engage in other forms of strenuous cardiovascular exercise while they are in middle age have a good chance of seeing the fruits of their labors later: They are nearly 90 percent less likely to develop dementia than women who were moderately fit, according to a Swedish study.
“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 dmentia,” the study's author, Helena Hörder, said.
To measure their peak cardiovascular capacity, over 190 women, average age 50, took a bicycle exercise test until they were exhausted. The average peak workload the researchers reported was 103 watts, a measure of power equal to the force exerted, multiplied by distance, divided by time.
Only five percent of the highly fit women developed dementia, while 25 percent of moderately fit women and 32 percent of the women with low fitness did.
The women were tested for dementia six times over the next 44 years. During that period, 44 of the women developed dementia. Five percent of the highly fit women developed dementia, while 25 percent of moderately fit women and 32 percent of the women with low fitness did. Highly fit women were 88 percent less likely to develop dementia than the moderately fit women.
And the women who had to stop the exercise test due to problems? Forty-five percent developed dementia decades later. “This indicates that negative cardiovascular processes may be happening in midlife that could increase the risk of dementia much later in life,” said Hörder.
More studies are needed. The women's fitness levels were measured only once, so changes in fitness over time, if any, were not part of the data. The small number of women involved in the study were all were from Sweden, Hörder pointed out, so the results may not apply to other populations.
The study is published in Neurology.