Older women who did an hour or two of strength training exercises each week had improved cognitive function a year later, scoring higher on tests of the brain processes responsible for planning and executing tasks. Researchers in B.C. randomly assigned 155 women aged 65 to 75 either to strength training with dumbbells and weight machines once or twice a week, or to a comparison group doing balance and toning exercises.

A year later, the women who did strength training had improved their performance on tests of so-called executive function by 10.9 per cent to 12.6 per cent.

Meanwhile, those assigned to balance and toning exercises experienced a slight deterioration -- 0.5 per cent.

The improvements in the strength-training group included an enhanced ability to make decisions and resolve conflicts. The study appeared in Archives of Internal Medicine.