A new study published in the medical journal of the American Academy of Neurology reports that young adults who run or participate in other cardio fitness activities may preserve their memory and thinking skills in middle age 43 to 55.
The study involved 2,747 healthy people with an average age of 25. For the first year of the study they underwent treadmill tests and repeated the tests 20 years later. They also underwent cognitive tests that were taken 25 years after the start of the study to measure verbal memory, executive function and psychomotor speed which is the relationship between thinking skills and physical movement.
The treadmill test, similar to a cardiovascular stress test, involved participants walking or running as the speed and incline increased until they could not continue or showed symptoms such as shortness of breath.
On the first test, participants lasted an average of 10 minutes on the treadmill. On the test conducted 20 years later, the number decreased by an average of 2.9 minutes. For every additional minute completed on the treadmill for the first test, they recalled 0.12 more words correctly on the memory test of 15 words; they also correctly replaced 0.92 more numbers with meaningless symbols in the test of psychomotor speed 25 years later even after adjusting for other factors such as smoking, diabetes and high cholesterol.
Those with smaller decreases of time completed on the treadmill test 20 years later were more likely to perform better on the executive function test than those who had bigger decreases.
Many studies show the benefits to the brain of good heart health, said study author David R. Jacobs, Jr. PhD with the University of Minnesota in Minneapolis. This is one more important study that should remind young adults of the brain health benefits of cardio fitness activities such as running, swimming, biking or cardio fitness classes.
These changes were significant, and while they may be modest, they were larger than the effect from one year of aging. Other studies in older individuals have shown that these tests are among the strongest predictors of developing dementia in the future. One study showed that every additional word remembered on the memory test was associated with an 18 percent decrease in the risk of developing dementia after 10 years. These findings are likely to help us earlier and identify and consequently prevent or treat those at high risk of developing dementia.
How Much Running Is Too Much?
While a number of studies have suggested that a moderate running regimen of two or three hours per week appears as best for longevity, recent research suggests that running too much may have a point of diminishing returns.
One study presented at the American College of Cardiologys annual meeting - states that people who either get no exercise or those that are high-mileage runners both tend to have shorter lifespans than moderate runners, but the reasons remain unclear. Cardiac risk or the use of certain medications were ruled out as factors.
The study evaluated data from more than 3,800 men and women runners with an average age of 46 that were involved in the Masters Running Study a web-based study of training and health information on runners aged 35 and above. Nearly 70 percent reported running more than 20 miles a week.
The runners also supplied information on their use of common painkillers NSAIDs or nonsteroidal anti-inflammatory medications such as ibuprofen and naproxen/Aleve - which have been linked with heart problems, as well as aspirin, which is known to be heart-protective. They also reported on known heart risk factors such as high blood pressure, diabetes, high cholesterol, family history of heart disease and smoking history.
The factors did not explain the shorter lives of high-mileage runners, according to the researchers. Use of NSAIDs was actually more common in runners who ran less than 20 miles weekly.
Our study didnt find any differences that could explain these longevity differences, said Dr. Martin Matsumura, co-director of the Cardiovascular Research Institute at the Lehigh Valley Health Network.
While Matsumura stressed that he doesnt tell patients not to run, he does tell high-mileage runners to stay informed about new research into the mileage-lifespan link as more becomes known. What we still dont understand is defining the optimal dose of running for health and longevity, he added.