A number of studies have found that physical exercise can help delay the onset of dementia, however the ability of exercise to slow the decline once dementia has set in is a more equivocal question. A large new study answers this question in the negative.
The study involved 494 people with mild-to-moderate dementia (average age 77; 61% male), of whom 329 were randomly assigned to a four-month aerobic and strength exercise programme and 165 were assigned to usual care. The exercise program was personalized, and involved two 60-90 minute gym sessions every week, plus a further hour at home. Nearly two-thirds of the exercise group attended more than three-quarters of the gym sessions.
While the exercise group did get physically fitter, their cognitive fitness (as measured by ADAS-cog score) actually worsened slightly.
The researchers emphasize that this was a specialized and intense exercise program, and in no way should it be taken to mean that gentle exercise, which is good for dementia sufferers, should be avoided.