Exercise is highly beneficial for brain health, improving cognition and mood, and reducing the risk of neurodegenerative diseases. Several new studies have demonstrated the profound impact exercise has on various biological systems, further explaining its ability to promote health and fight disease. In this feature, we explore the latest research on how exercise can protect brain health as we age.
Share on Pinterest Recent studies have explored how exercise can extend healthy lifespan and maintain brain health as we age. Image credit: FG Trade/Getty Images.
Exercise can lead to increased muscle strength, improved heart health, lower blood sugar levels, and many other health benefits.
Running on a treadmill, biking up steep hills, lifting weights, or taking a brisk walk during your lunch break can all have benefits beyond just improving your appearance and stamina.
Research evidence suggests that regular physical activity may elevate mood, reduce stress and enhance cognitive function, highlighting the deep connection between the body and mind.
However, people respond very differently to different forms of exercise, such as aerobic exercise and strength training.
It's well-known that regular exercise is essential to a healthy lifestyle, but some older studies suggest that intense exercise can have negative effects.
However, recent studies have shown that the life expectancy of elite athletes has increased slightly over the decades.
Exercise significantly enhances brain health by improving cognition and mood, and reducing the risk of neurodegenerative diseases by promoting neurogenesis and synaptic plasticity.
What does the latest evidence and expert opinion say about how regular physical activity can help maintain brain and whole-body health as we age?
In a new collaborative study led by the Stanford University School of Medicine, researchers investigated the underlying mechanisms by which exercise promotes overall health, and brain health in particular.
Understanding how exercise affects different organs at a molecular level will allow healthcare providers to customize exercise recommendations more effectively.
This knowledge could also pave the way for the development of drug therapies that mimic the effects of exercise for people who are unable to engage in physical activity.
The study, published in Nature, took around 10,000 measurements across around 20 different tissues and looked at the effects of eight weeks of endurance exercise in lab rats trained to run on a small treadmill.
The conclusions reveal that exercise has a significant effect on the immune system, stress response, energy production, and metabolism.
The researchers identified significant links between exercise and molecules and genes already known to be involved in a number of human diseases and tissue recovery.
Other recent papers from Stanford University School of Medicine researchers include a report in Nature Communications that looked at genetic and tissue changes associated with disease risk caused by exercise, and a paper in Cell Metabolism that looked at the effects of exercise on mitochondria, cellular energy producers, in various tissues in rats.
The Nature study looked at the effects of eight weeks of endurance training on a range of biological systems, including gene expression (transcriptome), proteins (proteome), fats (lipidome), metabolites (metabolome), DNA chemical tags (epigenome) and the immune system.
The researchers analyzed various tissues from rats that had been trained to run longer distances and compared them to tissues from sedentary rats.
The researchers looked at mitochondria in leg muscles, heart, liver, kidneys and white adipose tissue (which stores as body fat), as well as the lungs, brain and brown adipose tissue (the metabolically active fat that burns calories).
This comprehensive approach generated hundreds of thousands of results on non-epigenetic alterations in mitochondria and more than 2 million distinct epigenetic changes, providing a rich database for future studies.
In parallel with the primary aim of generating a database, there were some notable findings: for example, mitochondrial gene expression was altered by exercise across different tissues.
The researchers found that genes that were upregulated by training in the mitochondria of skeletal muscle from rats were downregulated in the mitochondria of skeletal muscle from patients with type 2 diabetes.
They also showed that training up-regulated mitochondrial genes in rat liver and down-regulated them in patients with cirrhosis.
These two findings suggest that endurance training may help improve muscle function and promote liver health in people with diabetes.
Finally, the researchers identified sex differences in how tissues in male and female rats responded to exercise.
After eight weeks, the male rats had lost about 5% of their body fat, but the female rats had lost less. However, the female rats maintained their initial fat percentage, whereas the sedentary female rats gained an additional 4% of their body fat over the course of the study.
The adrenal glands showed the greatest changes in mitochondrial gene expression after exercise in rats.
The study authors argue that the differences observed with exercise are primarily due to changes in mitochondrial gene expression in organs and tissues responsible for maintaining energy balance.
Another study completed by a research group at the University of Queensland in Australia and published in the journal Aging Cell demonstrated that exercise may halt or slow down age-related cognitive decline.
The researchers looked at gene expression in individual brain cells in mice and found that exercise had a significant effect on gene expression in microglia, immune cells in the central nervous system that support brain function.
Specifically, exercise reverted the gene expression patterns of aged microglial cells to those similar to those seen in young microglial cells.
Experiments depleting microglial cells demonstrated that they are required for the beneficial effects of exercise on the generation of new neurons in the hippocampus, a brain region crucial for memory, learning, and emotion.
The study also found that providing mice with access to a running wheel prevented or reduced the presence of T cells in the hippocampus with age.
These immune cells are generally absent from the young brain but increase in number with age.
Co-corresponding author Dr Jana Vukovic, Associate Professor and Director of the Neuroimmunology and Cognition Lab at the University of Queensland, explained the main findings to Medical News Today.
Vukovich explained: “[T]”The ageing process affects all the different cells in the brain, but it has the biggest impact on microglia, the brain's immune cells. Importantly, exercise reverts the genetic profile of microglia to that of a younger age.”
Understanding how exercise benefits brain health “is an important question for many scientists around the world,” Vuckovic noted, adding that she and her colleagues “propose that exercise alters the immune environment in the aging brain, thereby allowing immune cells to continue to support neuronal function.”
“The role of microglia beyond its involvement in clearing cellular debris is less well understood. We know that microglia support the birth of new neurons in the hippocampus, a structure important for learning and memory, but there are likely many other mechanisms at work.”
– Dr. Jana Vukovic
Ryan Glatt, CPT, NBC-HWC, a senior brain health coach and director of the FitBrain program at the Pacific Neuroscience Institute in Santa Monica, who was not involved in the studies, told MNT that the studies “highlight the multifaceted benefits of exercise on brain health, particularly through gene regulation, mitochondrial function and immune response.”
“They are providing valuable insights by blending molecular biology with practical health interventions for older adults,” he added.
For example, “exercise increases synaptic plasticity and blood flow, while also reducing inflammation and increasing the expression of neurotrophic factors such as BDNF,” Glatt explains. “These effects can synergistically improve memory, learning, and overall brain health.”
“Exercise influences gene expression related to brain plasticity, inflammation, and metabolism, while also enhancing mitochondrial function and modulating immune response. Hormonal changes caused by physical activity also contribute to improved mood and stress reduction.”
– Ryan Glatt, CPT, NBC-HWC
“While research is ongoing to optimize exercise programs for older adults, Pilates is a good starting point for those looking to build muscle,” Vuckovic noted.
Glatt agreed, adding that “aerobic activity – including cardio, strength and balance exercises – is particularly beneficial for brain health in both common and unique ways.”
“Activities that combine physical and cognitive challenges, like dance and tai chi, may be particularly effective for certain aspects of brain health,” Glatt said.
But he cautioned: “Exercise is good for brain health, but individual differences due to genetics and underlying health conditions may affect outcomes. More research is needed to determine long-term sustainability and the best types and intensities of exercise for different populations.”
