Numerous studies examine a single cognitive or physical performance measure and how it links to brain health in older adults, such as the relationship between gait speed and memory. Yet cognition and physical performance are comprised of multiple components. Cognition is comprised of various domains: memory, attention, language, and executive functions, to name a few. Similarly, physical performance comprises multiple components, such as strength, balance, and walking speed. A better understanding of the relationships between cognition, physical performance, and brain health in aging is important to assess multiple measures in the same study. A recent study by Wang and colleagues (2025) that was published in Neurology did just that.
Who participated in the study and what did they do?
Source: Shutterstock Photo ID 1806648967 By Krakenimages
The 1,140 70-year-old adults completed cognitive tests tapping memory, executive function, perceptual speed, verbal fluency, and visuospatial abilities. Physical performance tests measured grip strength, balance, walking speed, leg muscle strength, and functional mobility with a “sit to stand” task (how long does it take to rise from a seated position in a chair to a standing position five times in a row). And 721 of the participants completed brain magnetic resonance imaging (MRI). Importantly, participants completed different types of MRI scans, allowing for the assessment of different brain tissue types (gray matter, white matter) and neuropathology (white matter lesions, lacunar infarcts, and enlarged perivascular spaces—these are all indicators of cerebral small vessel disease, which can contribute to vascular dementia or Alzheimer’s disease).
What did they do with the data?
Wang and colleagues (2025) used a data-driven approach (latent class analysis) that classified each research participant into one of three groups:
- The optimal group. These individuals had the best scores on the cognitive and physical performance tasks.
- The intermediate group. These participants had reduced cognitive and physical performance scores relative to the optimal group.
- The physical deficit group. These participants’ cognitive performance was at a similar level as the intermediate group, but their physical performance was worse than the intermediate group.
Source: Shutterstock Photo ID2417326937 By Anton Vierietin
Once the research participants were classified into those three groups, Wang and colleagues (2025) looked at other variables, including the brain MRI data, to examine what other variables might differ between the groups.
What were the main study findings?
- Those in the optimal group were more educated (14 years) compared with the other groups (11 and 10 years).
- The intermediate and physical deficit group were more likely to be currently smoking, less physically active, obese, have diabetes, and have low alcohol intake compared with the optimal group
- Older adults classified into the physical deficit group experienced depression more frequently than the intermediate group
When looking at the brain MRI data, the intermediate group and the physical deficit group scored more poorly on multiple markers of brain health compared to the optimal group, such as:
- Greater white matter lesion burden
- Reduced white matter integrity
- Reduced gray matter volume and cortical thickness
- Increased ventricular volume
The physical deficit group exhibited further reductions in indicators of brain health compared with the intermediate group, including:
- Greater white matter lesion burden
- Reduced white matter integrity
- Reduced gray matter volume and cortical thickness
What were the study strengths?
- Solid sample size
- Comprehensive assessments of cognition, physical performance, and brain health
- Data-driven approach for classification of research participants
Conclusions
This study highlights the significant relationships between physical performance, cognition, and brain health. The study data were collected at a single time point, therefore, it was not possible to determine the temporal order of deficits. For instance, brain decline may precede physical performance impairment. Longitudinal studies are required to identify the temporal relationships among these variables. Nevertheless, this high-quality study extends our knowledge about the aging brain. The results highlight the pervasive nature of vascular risk factors (obesity, smoking, diabetes, physical inactivity) and multiple markers of brain health, including gray matter, white matter, and neuropathology. These data further highlight the importance of considering individual differences in cognitive and brain aging, and the appreciation of the variability in factors associated with healthy aging.
