Alzheimer’s disease causes brain cells (neurons) and the connections between the neurons (synapses), to degenerate over time and eventually die.  This loss of neurons has a detrimental effect on communication, repair, and metabolism within the brain.

Currently, there are few effective pharmacologic interventions to help manage the disease. Often the drugs that do exist have detrimental side effects.

There are two key areas of the brain that are affected by Alzheimer’s:

1. First is the prefrontal cortex, located right behind the forehead, which is critical for decision-making, focus, attention and personality. 

1. Second are the temporal lobes, located on each side of the brain. Each temporal lobe contains a structure called the hippocampus. These structures are critical to help form and retain new long-term memories.

You can mitigate many of the deleterious effects of Alzheimer’s through lifestyle interventions, like exercise. Simply moving the body on a regular bases can have immediate, long-lasting, protective benefits for the brain.

Exercise is essential for brain health for several reasons:

1. Exercise immediately increases the levels of chemicals in the brain (neurotransmitters) that help neurons communicate with each other. Neurotransmitters include dopamine, serotonin, and norepinephrine. Increases in these chemicals elevate the mood right after the activity. These "good mood" neurotransmitters continue long after exercise.

2. A single session of exercise can enhance the ability of people with dementia to shift and focus attention. The effects can last up to two hours. With exercise, there is an increase in the number of connections between the neurons (synapses).

3. Exercise can improve the reaction time of people with dementia. This can help the person to react more quickly when they are about to fall and possibly prevent the fall from happening.

4. Exercise produces new brain cells in the hippocampus, making it larger in volume, and thereby improving long-term memory.

5. Just like a muscle, the brain can grow with repeated exercise of the body. Exercise can increase the size and function of the hippocampi and prefrontal cortex, both of which are structures affected by Alzheimer's disease.

In conclusion, exercise has the ability to make everyone's brain more resilient. It may not prevent or cure dementia, but it can produce a bigger, stronger brain that will be more resistant to the development of dementia.

Walking has a neuroprotective benefit, which is important for people with Dementia/Alzheimer’s. 

Walking helps to increase neurotrophic factors such as BDNF (Brain Derived Neurotrophic Factor), which is the ‘miracle grow’ for neurons - a fertilizer for the brain. We have billions of brain cells, and BDNF helps keep them flourishing and strong. This is because when BDNF is released, it triggers a series of genes to grow new brain cells and pathways.  BDNF plays an important role in learning, memory, and behavior.

Walking has been shown to increase the neuronal activity of the Hippocampus, the center for memory and learning. This is one of the areas of the brain most affected by Alzheimer’s. Walking changes the electrical rhythms of the brain, which facilitate the production of BDNF, helping to maintain the health of the synapses.  This brain area responds to regular physical activity.  Electrical pulses occur in the Hippocampus with movement, but go completely silent with no movement, such as in cases of sedentary behavior.

Walking has shown to be salutary for cardiovascular health.   Blood flow to the brain provides oxygen and nutrients, which is important for cognitive health. Also, you can see lowered blood pressure with walking.

The lymphatic system is a vital part of the immune system, and its circulation helps defend the body against disease.  Walking confers positive impacts on the person’s immune system. People are stronger, able to fight off infections.  There is a powerful anti-inflammatory benefit to walking/exercise, with a decrease in inflammatory markers, IL-1, IL-6, C-reactive protein.  Sitting for long periods of time increases these proinflammatory markers.

It is important for the elderly to maintain a healthy musculoskeletal system. There is an increase in frailty in this population and falls are common. Walking helps to strengthen the joints, muscles, and bones, thereby decreasing the chances of falling and preventing serious injuries when falls occur.

There are many other benefits of walking, including the following: improving mood, regulating blood sugar, enhancing sleep health, boosting energy, promoting weight loss, lowering cholesterol, reducing stress, and increasing metabolism.

Depression is common in individuals living with dementia.

Studies show that spending as little as 1 hour in nature per week can enhance a person’s mood and have lasting effects for many weeks afterward.  Other studies show that spending as little as 1 hour exercising per week can decrease a person’s chance for future major depression by 12%.

Exercise in people who are suffering from major depression has shown to be as effective as drug therapy or cognitive therapy. There is less reliance on antidepressant medications, thereby reducing a multitude of potential side effects.

People with dementia may experience extended periods of stress, anxiety, and fear. It can cause these individuals to have chronically increased cortisol levels.

Although increased cortisol levels during brief periods of stress is a normal response and helps to prepare the body for 'fight or flight', chronically increased cortisol levels can have a deleterious effect on the entire body, including the brain.

The chronic release of cortisol, as may be experienced by a person with dementia, can increase the size of the emotional center of the brain, the Amygdala. An enlarged, overreactive amygdala can compound the stressful state.

The Hippocampus, which is the brain's center for memory and learning, can shrink with increased stress. This can affect a person's ability to remember and learn new things.

Chronic stress can also decrease the function of the Frontal Lobes, leading to changes in attention, personality, impulse control, decision making, speech, vision, mood, and social behavior.

Studies have shown that being out in nature lowers cortisol levels. This promotes a lower sympathetic state (fight or flight) and increases the parasympathetic state (healing and rest).

When the body is relaxed and safe, then it can actually heal itself.  When the body is in a constant state of alarm, it has difficulty healing.

As we take a peaceful walk through nature, the stress chemicals in our body decrease, allowing for the healing of the brain.

Exposure to sunlight is very beneficial to everyone, especially older adults.  The sun is a natural source to help our bodies make vitamin D.  The elderly are at higher risk for vitamin D deficiency, which can lead to weakened bones and frailty.  Vitamin D is utilized by over 2000 genes in our body. It's impact on the body cannot be emphasized enough. It is a vital hormone utilized by every organ system. For example, the immune system utilizes Vitamin D to help control inflammation.

In conclusion, being outside in nature and getting movement of the body, confers great benefits to the mind, body, and spirit, and helps to build resiliency. This resiliency is essential, so that we can fight off infections, heal more quickly from illnesses, and decrease our susceptibility to diseases.