Physical activity and exercise have an essential role in maintaining good physical and mental health. Exercise not only increases strength and endurance, but it can also improve our bodies in ways we often take for granted. For example, exercise can help us to better regulate our heart rate, respiration, and help us to better manage our stress response. Getting to know the science of exercise and how our bodies respond can help us to better understand why exercise is so important.

What is Exercise?   

Exercise is categorized as any activity that uses or works our muscles or other bodily systems. Examples of exercise can include jogging, running, swimming, weightlifting, or even movements during yoga sessions. Exercise can also be broken down into two main categories; aerobic and anaerobic.
Aerobic exercise is any physical activity that relies on oxygen to generate energy. Aerobic exercise uses oxygen in order to increase energy production and can be sustained over long time periods. Examples of aerobic activities could be low-intensity activities such as jogging or running, or higher intensity activities such as sprinting or swimming.

Anaerobic exercise is any activity that does not rely on oxygen to generate energy. It is typically a high-intensity activity and does not last for a long period of time. Examples of anaerobic activities could be burst activities such as weightlifting or sprinting.

Physiological Changes in our Bodies from Exercise   

When we exercise, there are a variety of physiological changes that occur in our body that allow it to adapt to the activity.

The Breathing System: As we exercise, our respiratory system is called upon to keep up with the demand for more oxygen to meet the energy requirements of our muscles. During aerobic exercise, the rate of inspiration increases, allowing us to take larger breaths in order to draw in more oxygen to take to the muscles to use as energy. The rate of expiration also increases, allowing us to expel more waste products such as carbon dioxide as energy is being produced.

The Cardiovascular System: During exercise, the cardiovascular system is also put to work. The heart rate increases in order to meet the energy demands of the muscles. During aerobic exercise, the heart rate increases because of the need to pump more oxygenated blood to the muscles. The rate of respiration also increases in order to keep up with the increase in oxygen being demanded by the muscles.

The Muscular System: During physical activity, the muscles are used to generate energy and contract in order to move. During aerobic exercise, the use of slow twitch muscle fibers become predominant as these fibers are better suited to repeated low-intensity activity. Over time, the muscles become more efficient at producing energy from aerobic activity resulting in improved strength and endurance.

During anaerobic exercise, the use of fast twitch muscle fibers become more prominent as these fibers are better suited for generating large amounts of energy quickly. With anaerobic activities such as weightlifting or sprinting, sudden bursts of energy are needed in order to generate movement. Over time, the muscles become more efficient at producing energy from anaerobic activity resulting in improved strength and power.

The Nervous System: The nervous system is also important in controlling the body during exercise. The autonomic nervous system has two main branches: the sympathetic (often referred to as the fight-or-flight system) and the parasympathetic (often referred to as the rest-and-digest system). During exercise, the sympathetic branch is active and causes the body to produce energy and increase alertness. This helps to keep a person motivated and able to continue exercising. The parasympathetic branch is also active during exercise and allows the body to naturally recover and relax. This helps to ensure that when a person stops exercising, the body is able to quickly and easily recover and return to a resting state.

The Endocrine System: The endocrine system is made up of a variety of glands in the body that produce hormones. During exercise the body releases certain hormones such as adrenaline and cortisol, which aid in the body’s response to exercise. These hormones help to increase alertness and focus and also help the body to produce energy.

The Metabolic System: The metabolic system is responsible for producing energy from the food we eat. During exercise, energy is produced from different types of nutrients and stored in the muscles and tissues. During aerobic exercise, the body relies predominantly on fat as an energy source, while during anaerobic activities, the body will rely on carbohydrates and proteins to produce energy.

The Immune System:
The immune system also plays an important role in exercise. During physical activity, the body is not able to efficiently fight off any potential infection from bacteria or viruses. The immune system helps to keep the body safe from any potential harm and also helps to reduce inflammation caused by exercise. Regular exercise helps to keep the immune system strong and allows the body to better recover from the occasional illness.

Benefits of Exercise   

Exercise has many benefits, both physical and mental. Here are some of the many benefits of exercise and how it can help to improve overall health:

• Strengthens the heart: Regular aerobic exercise has been shown to increase the size and strength of the heart, allowing it to efficiently pump more blood to the body.

• Increases blood circulation: Exercise increases the rate at which oxygenated blood is delivered to the body’s tissues and organs. This helps to improve overall health and allows the body to better utilize nutrients found in food.

• Strengthens the muscles: Regular exercise helps to increase the strength, size, and efficiency of the muscles. This can help to improve athletic performance and overall strength and can also reduce the risk of injury when lifting heavy objects.

• Improves balance and coordination: Exercise is essential to maintaining good balance and coordination. This can help to reduce the risk of falls and improve overall mobility.

• Improves mental health: Exercise has been shown to improve mood and reduce stress and depression.

• Helps with weight management: Regular exercise can help to burn excess calories and can help to maintain a healthy weight.

• Decreases the risk of disease: Studies have shown that regular exercise can help to reduce the risk of developing certain illnesses such as diabetes, heart disease, and some types of cancer.

Exercise has many benefits that can help to improve overall physical and mental health. The science of exercise can help us to better understand how our bodies respond to physical activity and to make better choices when it comes to exercise. Regular exercise and physical activity can help to strengthen our bodies and minds, and can ultimately help us to live healthier and longer lives.