Exercise Helps Your Brain  

By Shlomo Maital

  My mother, Sally Malt, lived to 105.  She was sound of mind to the end.  She had an exercise machine that she used without fail every day —  a treadmill with handles for upper body exercise.

   When I used to visit her, I would watch her work out – and then do my own workout.  And I follow her model.  I work out in the Technion fitness room, focusing on abs and upper body and legs, and do a 3 km. walk regularly down and up a steep hill. 

     Dana Smith, writing in the New York Times, explains why exercise for seniors can be important for the health of their brains.  Here is what she writes: *

* NYT. How Exercise Strengthens Your Brain.  April 2, 2024.

     “Physical activity improves cognitive and mental health in all sorts of ways. Here’s why, and how to reap the benefits.

       “Exercise offers short-term boosts in cognition. Studies show that immediately after a bout of physical activity, people perform better on tests of working memory and other executive functions. This may be in part because movement increases the release of neurotransmitters in the brain, most notably epinephrine and norepinephrine.

     The neurotransmitters dopamine and serotonin are also released with exercise, which is thought to be a main reason people often feel so good after going for a run or a long bike ride.

      “The brain benefits really start to emerge, though, when we work out consistently over time. Studies show that people who work out several times a week have higher cognitive test scores, on average, than people who are more sedentary. Other research has found that a person’s cognition tends to improve after participating in a new aerobic exercise program for several months.

     “Perhaps most remarkable, exercise offers protection against neurodegenerative diseases. “Physical activity is one of the health behaviors that’s shown to be the most beneficial for cognitive function and reducing risk of Alzheimer’s and dementia,” said Michelle Voss, an associate professor of psychological and brain sciences at the University of Iowa.

    “How does exercise do all that?

        “It starts with the muscles. When we work out, they release molecules that travel through the blood up to the brain. Some, like a hormone called irisin, have “neuroprotective” qualities and have been shown to be linked to the cognitive health benefits of exercise, said Christiane Wrann, an associate professor of medicine at Massachusetts General Hospital and Harvard Medical School who studies irisin. (Dr. Wrann is also a consultant for a pharmaceutical company, Aevum Therapeutics, hoping to harness irisin’s effects into a drug.)

      “Good blood flow is essential to obtain the benefits of physical activity. And conveniently, exercise improves circulation and stimulates the growth of new blood vessels in the brain. “It’s not just that there’s increased blood flow,” Dr. Voss said. “It’s that there’s a greater chance, then, for signaling molecules that are coming from the muscle to get delivered to the brain.”

      “ Once these signals are in the brain, other chemicals are released locally. The star of the show is a hormone called brain-derived neurotrophic factor, or B.D.N.F., that is essential for neuron health and creating new connections — called synapses — between neurons. “It’s like a fertilizer for brain cells to recover from damage,” Dr. Voss said. “And also for synapses on nerve cells to connect with each other and sustain those connections.”

       “A greater number of blood vessels and connections between neurons can actually increase the size of different brain areas. This effect is especially noticeable in older adults because it can offset the loss of brain volume that happens with age. The hippocampus, an area important for memory and mood, is particularly affected. “We know that it shrinks with age,” Dr. Roig said. “And we know that if we exercise regularly, we can prevent this decline.”

       “Exercise’s effect on the hippocampus may be one way it helps protect against Alzheimer’s disease, which is associated with significant changes to that part of the brain. The same goes for depression; the hippocampus is smaller in people who are depressed, and effective treatments for depression, including medications and exercise, increase the size of the region.”