Nathan Kerr, a 27-year-old postdoctoral fellow at the University of Missouri, often finds his 81-year-old mentor, Frank Booth, running on a treadmill during office visits. Booth, who has spent decades researching physical inactivity, exemplifies his mission of promoting active lifestyles.
While many scientists focus on the benefits of exercise, Booth explores the consequences of not moving—and his latest findings reveal a critical connection between physical activity, brain health, and overall well-being.
The Brain-Muscle Connection
In a recent study published in the Journal of Applied Physiology, Booth and Kerr discovered that just 10 days of physical inactivity can lead to significant changes in the brain.
Specifically, they observed insulin resistance and an increase in reactive oxygen species (ROS) production in the hippocampus—the brain region responsible for memory and learning.
Even more concerning, muscle disuse during this period elevated markers for proteins associated with Alzheimer’s disease. Alzheimer’s is an irreversible neurodegenerative condition that ranks as the fifth leading cause of death in older adults.
This study provides compelling evidence that physical activity is crucial not only for physical health but also for maintaining brain health and potentially delaying the onset of neurodegenerative diseases.
A Declining Health Span
Booth highlights an alarming trend: while Americans now live longer—average lifespans have increased from the mid-60s in the 1940s to the high 70s today—the number of disease-free years, or “health span,” has declined significantly after age 65.
Conditions like type 2 diabetes, often linked to physical inactivity, have surged alongside longer lifespans.
Booth explains that physical inactivity’s effects on insulin resistance, already well-documented in the body, are now being observed in the brain. This finding underscores the importance of physical activity in preserving both physical and cognitive health.
Small Changes, Big Impact
Fortunately, making a difference doesn’t require drastic changes. Booth points out that people who transition from no exercise to occasional exercise often see the greatest health improvements—even more than those who increase from occasional to regular exercise. The key is to start moving, no matter how small the steps may seem.
Research also shows that the early signs of Alzheimer’s may begin decades before diagnosis, often in a person’s 40s or 50s.
This makes it critical to adopt healthy habits, including regular physical activity, earlier in life. Booth emphasizes, “If you can develop good habits in terms of exercise and lifestyle earlier, your brain will thank you later on.”
A Shared Effort for Better Health
The study, conducted in collaboration with researchers Laurel Grisanti and Scott Rector, further reinforces the importance of staying active for overall health. Booth and Kerr’s findings reveal how closely brain and muscle health are intertwined and demonstrate that even brief periods of inactivity can have measurable consequences.
For Booth, the message is clear: promoting physical activity isn’t just about extending lifespans but about improving the quality of life. “We want to help people live more enjoyable lives in their later years,” he said.
Start Today for a Healthier Tomorrow
Whether you’re in your 20s or 80s, the benefits of physical activity are undeniable. Developing even modest exercise habits can make a profound difference in reducing the risk of chronic illnesses and maintaining cognitive health. As Booth says, the most important step is simply to begin—your brain and body will thank you.
If you care about brain health, please read studies about vitamin D deficiency linked to Alzheimer’s and vascular dementia, and higher magnesium intake could help benefit brain health.
For more information about brain health, please see recent studies about antioxidants that could help reduce dementia risk, and coconut oil could help improve cognitive function in Alzheimer’s.
The research findings can be found in the Journal of Applied Physiology.
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