A new study has found that exercise can stimulate brain-boosting molecules when muscles are active. By innervating muscle-tissue models, researchers discovered that the same nerves that signal muscles to move can also send neurotrophic factors into the brain. Some evidence suggests that exercise can reverse or delay cognitive decline associated with aging. Future studies should allow for variations among individuals to see how physical activity can affect this. Exercise plays a role in brain health by triggering molecules involved in cognitive function to be released by muscles. The study, published in Proceedings of the National Academy of Sciences, shows that when nerves that stimulate muscles are activated, they also send signals to the brain by secreting bioactive molecules and nanoparticles that enhance brain function.
The findings from the study highlight the importance of maintaining musculoskeletal health for counteracting neurological degeneration. Hyunjoon Kong, PhD, from the University of Illinois Urbana-Champaign, explained that maintaining neuronal innervation in muscles is crucial for producing biological factors beneficial to the brain. With regular muscle contractions, muscles not only secrete these beneficial factors but also help sustain the innervation necessary for nerves to continue signaling muscles. The signaling is essential for regulating the release of neurotrophic factors into the brain. The study involved stimulating muscles with glutamate to see how nerve function would respond. Researchers used models of muscle tissue, one that was innervated and one that was not, and discovered that the innervated tissue sent more signals to the brain. Since neuron function in muscles can decrease with age or injury, researchers were interested in how this loss would affect brain health.
While the researchers did not observe people exercising in the study, they focused on muscle models to understand brain-body interactions. Previous studies have shown correlations between regular physical activity and cognitive function improvements. Findings suggest that individuals who regularly perform aerobic exercises tend to have larger hippocampi and improved performance on spatial memory tests. Future studies that use human participants to fully comprehend the effects of exercise on the brain would need to allow for variations in age, baseline cognitive function, and health status. The duration required to observe the effects of exercise on cognitive function can vary based on the type, intensity, and frequency of exercise.
Some notable benefits of regular exercise for brain health include improved cardiovascular and cognitive function. Activities like boxing have been used to aid individuals with conditions like Parkinson’s disease. Aerobic exercises, such as running, swimming, and cycling, are known for their positive impacts on brain function. Activities that combine physical and cognitive demands, like dance and team sports, may offer additional benefits due to their requirement for coordination, rhythm, and executive functions. Physical activity may potentially reverse or delay cognitive decline associated with aging by helping maintain neuromuscular junctions between nerves and muscles. Elderly individuals can still possess functional muscles capable of producing factors critical for brain function with appropriate training or stimulation for muscle contractions.
While a sedentary lifestyle can be associated with a higher risk of cognitive decline, exercise is recognized as a supportive intervention for individuals with compromised cognitive functions. It can enhance blood flow to the brain, reduce inflammation, and stimulate the release of growth factors that may help maintain or improve cognitive function. Although most studies suggest that exercise can contribute to better overall brain health and a slower rate of decline, the evidence on its ability to reverse existing cognitive impairment is inconclusive. More extensive research is needed to understand the potential of exercise for reversing cognitive deficits.
