Better Cardiorespiratory Fitness Linked to Improved Cognitive Health

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Better cardiorespiratory fitness (CRF) was linked to better cognitive performance among a group of older adults. This correlation was seen across multiple domains susceptible to age-related cognitive decline, including memory, processing speed and executive function.

CRF, a modifiable indicator of aerobic capacity improved through regular aerobic exercise, has been previously connected with a lower risk of age-related cognitive decline and dementia. However, the exact nature of this relationship remains unclear due to variability in methods used to measure both CRF and cognitive function, along with the limited sample sizes of previous studies.

“Fundamental questions regarding the link between CRF, assessed by a graded exercise test, and cognition in ageing remain,” wrote a team of investigators led by Lauren E. Oberlin, Ph.D., associated with the Department of Neuroscience at AdventHealth Orlando and the Department of Psychiatry at Weill Cornell Medicine. “A better understanding of these relationships might help to inform public health recommendations for maintaining fitness levels to preserve cognitive health in older adulthood.”

The Investigating Gains in Neurocognition in an Intervention Trial of Exercise (IGNITE) trial was a 12-month multisite aerobic intervention designed to determine the potential association between CRF and brain health among adults aged 65 to 80 years, as well as identify any factors that might impact this connection. Exclusion criteria included a history of neurological conditions, a history of severe mental illness, current major depression or substance use disorder, and a recent history or treatment for severe cardiovascular events.

CRF was assessed using a treadmill-based graded exercise test, and the connections between CRF and each of the cognitive domains were measured using linear regression models. The potential moderators included age, sex, education, beta-blocker usage and carrying the APOE4 gene — a risk factor for Alzheimer’s disease.

Cognitive performance was assessed across five areas: episodic memory, processing speed, working memory, executive function/attention and visuospatial skills.

IGNITE enrolled 648 adults with a mean age of 69.88 years and an average of 16.32 years of education. Most were women (71.1%). Among the 640 people genotyped, 174 (27.2%) were carriers of the APOE4 gene. Participants’ CRF, measured by maximum oxygen consumption (VO₂max), averaged 21.68 mL/kg/min.

Higher CRF was linked to better cognitive performance in all these areas, regardless of age or whether individuals carried the APOE4 gene.

Women, individuals with less education and those taking beta-blockers showed a stronger connection between CRF and improvements in specific cognitive functions, particularly processing speed and executive function/attentional control.

Older age was linked to worse cognitive performance when controlling for education, body mass index (BMI), sex and site. Additionally, after adjusting for controls, more years of education were connected with a better performance across all cognitive domains.

Investigators noted the cross-sectional design as a limitation of the study and encourage future prospective studies to focus on the trajectories of change and the role of moderators. As the sample was comprised of cognitively healthy, sedentary older individuals, other studies recruiting more varied populations — such as physically active seniors, those with cognitive impairments and a greater proportion of men — could help to confirm the findings. An additional limitation was not including all of the possible cognitive domains, such as language.

“These data emphasize CRF as an important health factor and therapeutic target for preserving multidomain cognitive functioning in late adulthood,” investigators concluded. “These findings also clarify the moderating role of several factors, which might help to inform public health recommendations and the development of individualized fitness prescriptions to optimize cognitive health in older adulthood.”