Staying Fit to Stay Sharp

Cardiorespiratory fitness may keep cognitive abilities from declining in older adults

(RxWiki News) Memory and thinking tend to slow down in older adults, but those who stay physically active may keep their minds running smoothly.

A new study found that older adults who were more physically fit performed as well as younger people in memory tests. Cardiorespiratory fitness (CRF) has previously been shown to improve planning and decision-making in older people.

The more fit the older adult, the better his or her memory was, this study found. Fitness also affected the brain's executive functions, such as the ability to plan, make decisions and organize information. Being fit did not appear to affect memory or executive functions in younger people.

Scott M. Hayes, PhD, professor at Boston University School of Medicine and associate director of the Neuroimaging Research for Veterans Center at the VA Boston Healthcare System, led this study.

"Our findings that CRF may mitigate age-related cognitive decline is appealing for a variety of reasons, including that aerobic activities to enhance CRF (walking, dancing, etc.) are inexpensive, accessible and could potentially improve quality of life by delaying cognitive decline and prolonging independent function,” Dr. Hayes said in a press release.

Dr. Hayes and team compared 33 adults who ranged in age from 18 to 31 with 28 adults who were 55 to 82. The young adults were students at Boston University in bachelor’s degree programs. The older adults were drawn from various sources, such as other research programs on memory disorders or Alzheimer’s disease.

Each study patient underwent exercise testing on a treadmill to assess his or her level of fitness. Patients also took memory and cognitive tests.

Dr. Hayes and colleagues used intellectual test results — rather than years of education — to assess mental capabilities. The study patients took standardized tests to assess memory, planning and problem-solving abilities, as well as a lab test in which they learned face-name associations to test memory.

Older adults who were more fit — they had higher CRF levels — performed as well as young adults in planning, problem-solving and organizing information. Fitness did not appear to affect young adults’ memory or executive functions.

Young adults performed better than older adults on long-term memory, Dr. Hayes and team found. However, older adults who were more fit performed better on memory tests than older adults who were less fit.

"More research is needed to explore the specific mechanism of how physical fitness enhances brain structure and function as well as to clarify the impact of specific exercise programs (i.e. strength, aerobic or combined training) or dose of exercise (frequency, intensity, duration) on a range of cognitive functions," Dr. Hayes said.

This study was published Dec. 22 in the Journal of Gerontology: Psychological Sciences.

This research was funded by the Department of Veterans Affairs, Rehabilitation Research & Development Service and Clinical Science Research & Development Service. The Massachusetts Alzheimer's Disease Research Center and Boston University Alzheimer's Disease Center assisted in patient recruitment.

The authors disclosed no conflicts of interest.

Review Date: 
December 23, 2014