Light, physical activity reduces brain aging

April 19, 2019

Science Daily/Boston University School of Medicine

Incremental physical activity, even at light intensity, is associated with larger brain volume and healthy brain aging.

Considerable evidence suggests that engaging in regular physical activity may prevent cognitive decline and dementia. Active individuals have lower metabolic and vascular risk factors and these risk factors may explain their propensity for healthy brain aging. However, the specific activity levels optimal for dementia prevention have remained unclear.

The new 2018 Physical Activity-Guidelines for Americans suggest that some physical activity is better than none, but achieving greater than 150 minutes of moderate-to-vigorous (MV) physical activity per week is recommended for substantial health benefits.

Using data from the Framingham Heart Study, researchers found that for each additional hour spent in light-intensity physical activity was equivalent to approximately 1.1 years less brain aging.

According to the researchers, these results suggest that the threshold of the favorable association for physical activity with brain aging may be at a lower, more achievable level of intensity or volume.

"Every additional hour of light intensity physical activity was associated with higher brain volumes, even among individuals not meeting current Physical Activity-Guidelines. These data are consistent with the notion that potential benefits of physical activity on brain aging may accrue at a lower, more achievable level of intensity or volume," explained Nicole Spartano, PhD, research assistant professor of medicine at Boston University School of Medicine (BUSM).

"We have really only just begun to uncover the relationship between physical activity and brain health." Spartano emphasizes the need to explore the impact of physical inactivity on brain aging in different race, ethnic, and socio-economic groups. She is leading a team effort to investigate these patterns at multiple sites all over the country. "We couldn't do this research without the commitment of the Framingham Heart Study participants who have given so much to the medical community over the years. Our research also hinges on the multi-disciplinary team of investigators at Boston University and external collaborators." She also acknowledges the importance of funding for research in this area and is grateful for support from the National Institute on Aging, American Heart Association, and Alzheimer's Association.

https://www.sciencedaily.com/releases/2019/04/190419112331.htm

Exercise can reduce stroke risk

July 18, 2013

Science Daily/University of Alabama at Birmingham

A new study from researchers at the University of Alabama at Birmingham (UAB) is one of the first to study the relationship between exercise and stroke in a large biracial cohort of men and women in the United States. The findings are published in the American Heart Association Journal Stroke.

Using 27,000 stroke-free blacks and whites ages 45 and older in the United States from the Reasons for Geographic and Racial Differences in Stroke (REGARDS) study cohort, researchers examined the association of self-reported physical activity with incident of stroke.

Participants were classified at baseline as being in active (i.e., no workouts in a typical week), moderately active (workouts one to three times per week) or vigorously active (workouts more than four times per week), and they were followed for an average of 5.7 years.

The results showed that physical inactivity was reported by 33 percent of participants and was associated with a 20 percent increased risk of stroke. Those who reported they exercised at least four times a week were less likely to experience a stroke or mini-stroke. Among men, only those who exercised four or more times a week had a lower stroke risk. Among women, the relationship between stroke and frequency of activity was less clear.

"The protective effect of intense physical activity may be through its impact on traditional risk factors such as hypertension and diabetes," explained Virginia Howard, Ph.D., UAB professor of epidemiology and senior study author.

"These findings confirm past results of studies done in only men or only women in limited geographical areas," Howard said. "By using the REGARDS cohort, our study was able to use a larger and more diverse population to show that participating in regular physical activity is associated with lower stroke risk."

Howard added that stroke is preventable, and physical activity is a major modifiable risk factor for stroke. "This should be emphasized more in routine physician check-ups, along with general education on the proven health benefits of regular physical activity on other stroke-risk factors including high blood pressure, diabetes and obesity," Howard said.

Study limitations highlighted include that the results are based on self-reported levels of physical activity, and self-reported data may not be a reflection of the truth. Also, investigators did not have data on the type or duration of the exercise in which people engaged, nor the number of sessions. Howard suggested future studies should consider different ways to measure physical activity through: use of more questions; devices such as accelerometers and heart monitors that can provide more objective data; and capturing information on other dimensions of physical activity such as frequency, intensity and duration.

http://www.sciencedaily.com/releases/2013/07/130718130456.htm