Basic Brain Anatomy

The brain is the control center of the body, and different areas work together to help us move, think, and stay balanced. When we exercise, several key parts of the brain play a role. The cerebrum, the largest part of the brain, helps us plan and coordinate movements. The cerebellum, located at the back of the brain, is responsible for balance and fine-tuning our movements, making sure we stay steady on our feet. The motor cortex, found in the cerebrum, sends signals to our muscles, telling them when and how to move. Deep inside the brain, the basal ganglia help control smooth, coordinated movement, while the hippocampus, a key area for memory, benefits from exercise by growing new brain cells. Even the brainstem plays a role by regulating heart rate and breathing, helping our body adjust to physical activity.  Each of these areas relies on a constant supply of oxygen and nutrients delivered through blood flow.

Blood Flow and the Brain

Even  though your brain makes up only about 2% of your body weight, it uses 15-20% of your blood supply.   Your brain needs a constant flow of oxygen and nutrients to function at its best. At the same time, blood circulation helps clear away waste products, like carbon dioxide, that can build up and slow things down.

Your brain gets its blood supply from four key arteries:

• Carotid arteries (left and right) – These run along the sides of your neck, feeding the front part of your brain, where thinking and movement planning happen.

• Vertebral arteries (left and right) – These travel up your spine and supply the back of your brain, which helps with balance and coordination.

Together, these arteries form a safety net called the Circle of Willis, which helps keep blood flowing even if one pathway is blocked or narrowed.

Why does this matter for exercise? Movement increases blood flow, helping your brain get the oxygen it needs to stay sharp, process information, and keep you steady on your feet. Whether it’s a brisk walk, stretching, or strength training, every bit of movement supports your brain health.

Exercise has powerful effects on brain chemistry, which helps improve mood, memory, and cognitive function. Here are some ways that  exercise influences brain chemistry:

Neurotransmitter Production

Exercise has a powerful effect on the brain, in part because it boosts the production of key neurotransmitters, the chemical messengers that help brain cells communicate. These neurotransmitters play a crucial role in mood, focus, and cognitive function. 

One important neurotransmitter influenced by exercise is dopamine, which helps with motivation, learning, and pleasure. Regular physical activity increases dopamine levels, which may improve focus and prevent cognitive decline, making it easier to stay engaged and motivated in daily activities. 

Another key neurotransmitter is serotonin, often called the "feel-good" chemical. Exercise, especially aerobic activities like walking or dancing, helps increase serotonin levels, reducing stress, anxiety, and symptoms of depression. This is one reason why people often feel a sense of well-being after being active. 

Additionally, exercise boosts norepinephrine, a neurotransmitter that sharpens attention, improves reaction time, and enhances cognitive performance. By increasing norepinephrine, physical activity helps the brain stay alert and responsive, making it easier to concentrate and process information. 

Together, these neurotransmitters create a powerful brain-boosting effect, helping to improve both mental and emotional well-being with every movement you make.

Brain-Derived Neurotrophic Factor (BDNF)

Exercise plays a powerful role in keeping your brain healthy. One of the key reasons for this is a special protein called Brain-Derived Neurotrophic Factor (BDNF). Think of BDNF as "fertilizer for the brain" because it helps brain cells (neurons) grow, stay strong, and form new connections. This is especially important as we age, since the brain naturally loses some of its flexibility over time. Higher levels of BDNF support neurogenesis, particularly in the hippocampus (the area responsible for memory and learning).  When BDNF levels are high, the brain is better at adapting, storing information, and staying sharp.  This helps protect against cognitive decline and conditions like dementia.

BDNF is enhanced through regular physical activity. Exercise increases blood flow, which in turn stimulates the release of BDNF, improving communication between brain cells and making it easier to learn new skills, remember details, and even regulate mood. Activities like walking, strength training, and balance exercises all contribute to this brain-boosting effect. Studies show that people who engage in regular movement tend to have higher levels of BDNF, which may help slow age-related memory loss and keep the brain resilient. Later in the lesson we will discuss what types of exercise are particularly effective for increasing BDNF.

Endorphin Release (Natural Pain Relievers)

Endorphins are the brain’s natural painkillers and mood boosters, released in response to physical activity, stress, or pain. These neurochemicals interact with opioid receptors in the brain, reducing the perception of pain and promoting a sense of well-being and relaxation. Exercise, especially aerobic activities like walking, running, or dancing, triggers endorphin release, often leading to a "runner’s high" or an improved mood. By increasing endorphin levels, regular physical activity helps reduce stress, combat anxiety and depression, and enhance overall mental resilience, making exercise a powerful tool for both physical and emotional well-being.

Increased Glucose and Energy Metabolism

The brain relies on glucose as its primary source of energy, using about 20% of the body’s total glucose supply despite making up only a small percentage of body weight. Glucose fuels neurons, allowing them to generate electrical signals, process information, and communicate effectively. Without a steady supply, cognitive functions like memory, focus, and decision-making can decline. Exercise helps regulate glucose metabolism by improving insulin sensitivity, ensuring that the brain receives a stable flow of energy. 

Setting Realistic Goals and Tracking Progress

Setting realistic goals and monitoring progress can keep you accountable. Whether using a simple journal, a step counter, or a fitness app, having a record of your workouts encourages consistency and helps you build long-term habits. Most importantly, tracking your progress reinforces the idea that every small step matters.  Staying active, no matter the pace, contributes to better health and well-being over time.

Tracking your progress is a key part of staying motivated and committed to an exercise routine. When you start a new program, small improvements may not always be immediately noticeable, but keeping track of your activities helps you see how far you’ve come over time. By recording what exercises you do, how long you do them, and how you feel afterward, you can celebrate achievements—whether it’s walking longer distances, lifting heavier weights, or simply feeling more energized throughout the day.

Progress tracking also helps ensure that your routine remains safe and effective. By noting how your body responds to different exercises, you can identify what works well and what may need adjustment. If certain movements cause discomfort, you can modify them, and if a particular activity feels too easy, you can gradually increase the intensity.