Does physical exercise prevent dementia?

The theory that physical exercise may play an important role in the prevention of cognitive impairment and dementia in the elderly has received much attention in recent years. This Goethe University Frankfurt study evaluated the effects of regular exercise on brain metabolism. The SMART study (Sport and Metabolism in Older Persons), a randomised controlled trial, investigated the memory, movement-related parameters, cardiopulmonary fitness and cognitive performance of 60 participants aged between 65 and 85. Brain metabolism and structure was initially measured using magnetic resonance tomography (MRT) and magnetic resonance spectroscopy (MRS). Participants then engaged in individually-adapted 30-minute training sessions using an exercise bike three times a week over a twelve-week period. After re-examination at the end of the exercise programme, researchers determined that physical activity had influenced brain metabolism. More specifically, exercise appeared to inhibit the accumulation of choline, a metabolite that in increased levels is associated with loss of nerve cells and the development of Alzheimer's disease. Whilst in the control group, cerebral choline levels increased, levels remained stable in the training group. The researchers concluded that physical exercise not only improves physical fitness but also protects nerve cells. Read the original research article here.