Having powerful legs could help prevent age-related cognitive decline according to new research published in Gerontology. Researchers looked at female twins over a 10-year period and found that the stronger twins — those who scored higher in Leg Explosive Power tests, which measure the force and velocity of a person's leg extension — appeared to be aging like people more than five years younger.
Geriatrician Claire Steves and her team from King's College London tested leg power in 324 women, with an average age of 55, and then conducted computer tests for memory, speed of processing, and reasoning. Among all the participants, they found that the top quartile [the middle number between the smallest and median] in strength appeared to be 19 years "younger" than the bottom quartile for strength after the 10 years, Steves says.
Even more frail subjects can perform leg-power tests, Steves says, so they're more useful in the context of this study than tests strictly measuring strength. "Leg power is a sensitive marker of the kind of physical activity that can influence cognitive aging," Steves says. "This is even controlling for all the factors that twins share."
Using twins as study subjects is also helpful because it enables scientists to reduce the number of variables that can skew results, as twins grow up in the same environment with many of the same influences, and if they're identical, they even have the same genes. In terms of this study, that means that Steves and her team were able to conclude with a good degree of confidence that leg power appears to be the variable contributing to the anti-aging effect.
The bottom line? Improving leg power by walking, running, jumping, or even skipping more often could help healthy people improve cognitive abilities as they age.