In contrast to the previous two study Sabia et al., (2017) study tested the premise that physical activity in midlife doesn't minimise the risk of dementia. In the observational study over 10,000 civil service workers, aged between 35 and 55 years, were assessed using a questionnaire monitoring physical activity seven times; a battery of cognitive tests was administered up to four times. Between 1985 and 2013 the participants were advised to do 2.5 hours/week or more. Researchers determined there was no association between exercise and risk of dementia after the mean 27 year follow up, a 1.00, 95% confidence interval 0.80 to 1.24; 329 cases of dementia were recorded. The study found that female sex, increasing age and education lower than diploma
