Exercise

Exercise is any physical activity that is done to improve or maintain physical fitness, health, and overall well-being. Exercise can range from simple movements like walking and stretching to more vigorous activities like weightlifting and running.

When we exercise, several physiological processes occur in our bodies, including those involving the respiratory system, nervous system, musculoskeletal system, and metabolic system.

What systems are involved in exercise

Respiratory system: During exercise, the respiratory system works to deliver oxygen to the muscles and remove carbon dioxide. This is achieved through an increase in breathing rate and depth, which helps to increase oxygen uptake and carbon dioxide removal. The lungs also work harder to expand and contract to accommodate the increased demand for oxygen.

Nervous system: The nervous system plays a vital role in exercise by coordinating muscle movement and regulating heart rate, blood pressure, and respiration. When we exercise, signals from the brain are sent to the muscles to contract and produce movement. Additionally, the sympathetic nervous system is activated to increase heart rate and blood pressure, while the parasympathetic nervous system works to decrease heart rate and blood pressure during rest and recovery.

Musculoskeletal system: Exercise puts stress on our muscles, bones, and joints, which stimulates adaptations in these systems to improve strength, endurance, and flexibility. The musculoskeletal system responds to exercise by increasing muscle fiber size and number, strengthening bones, and improving joint flexibility and range of motion. Additionally, exercise helps to maintain muscle mass and prevent muscle loss that can occur with aging.

Metabolic system: the metabolic system is also involved in exercise and plays an important role in energy production. During exercise, our bodies require energy to power muscle contractions and other physiological processes. This energy is produced through metabolic processes that involve the breakdown of carbohydrates, fats, and proteins.

When we exercise, the demand for energy increases, and our metabolic rate increases to meet this demand. This increase in metabolic rate can persist for several hours after exercise, which is why regular physical activity can help to boost metabolism and improve overall energy expenditure.

Additionally, exercise can improve insulin sensitivity, which helps to regulate blood glucose levels and prevent the development of insulin resistance and type 2 diabetes. Exercise also helps to promote healthy body composition by increasing muscle mass and reducing body fat, which can further improve metabolic health.

Exercise as a beneficial stress

Exercise can be considered a beneficial stressor for the adrenal system. The adrenal system is responsible for producing and releasing hormones in response to stress, including the stress of exercise.

During exercise, the adrenal system is activated, leading to the release of hormones such as adrenaline and cortisol. These hormones help to increase heart rate, blood pressure, and glucose uptake, which are important for providing the body with the energy it needs to sustain physical activity.

Over time, regular exercise can help to improve the body’s ability to cope with stress by strengthening the adrenal system and improving the body’s response to stress. This can help to reduce the risk of chronic stress-related conditions such as anxiety and depression.

However, it’s important to note that excessive exercise or overtraining can lead to a state of chronic stress in the body, which can have negative effects on adrenal function and overall health. Therefore, it’s important to engage in exercise that is appropriate for your fitness level and to allow for adequate recovery time between workouts.

Exercise can be a beneficial stressor for the adrenal system when done in moderation and with proper rest and recovery. By incorporating regular physical activity into our lives, we can improve our overall health and well-being while reducing the risk of stress-related conditions.

Beneficial stress from exercise vs damaging distress

Beneficial stress, such as exercise, is stress that is short-term and has positive effects on the body. It helps to improve physical and mental health, increase resilience to stress, and promote overall well-being. Exercise is a form of acute stress that causes a brief and controlled increase in stress hormone levels, followed by a recovery phase.

We have control over stress, if we choose it, if we enjoy it, if we overcome this and perhaps go through it in a playful manner – it may not even be considered stress despite hormonally having all the signs of it.

On the other hand, damaging stress is long-term and has negative effects on the body. Chronic stress, which can be caused by ongoing problems such as financial troubles, relationship difficulties, or job-related stress, can have negative effects on health. Chronic stress can lead to a prolonged increase in stress hormone levels, which can result in physical and mental health problems, including anxiety, depression, heart disease, and immune system dysfunction.

The stress over our lives, over which we have limited control is something entirely different and when the body cannot cope or recover from it, it is very painful and naturally bad for health.

When experiencing stress is negative, also called “distress” our body is prioritizing “right-now”, being alert to potential dangers, and the resource expenditure is aimed at managing with present situation meaning that fewer resources are left for later. This cannot be good in terms of aging.

One of the key differences between beneficial and damaging stress is the duration and intensity of the stress. Beneficial stress is short-term and can be easily managed, whereas damaging stress is long-term and persistent, and can be difficult to manage without intervention. Beneficial stress can help to promote growth and adaptation while damaging stress can lead to negative health outcomes.

Another difference between beneficial and damaging stress is the way the body responds to it. Beneficial stress, such as exercise, triggers a physiological response that helps the body adapt to the stress and return to homeostasis. Damaging stress, on the other hand, can lead to a chronic state of activation that can damage the body over time.

Beneficial stress, such as exercise, has positive effects on the body and can improve physical and mental health, while damaging stress, which is long-term and persistent, can have negative effects on health and increase the risk of chronic diseases.

Types of exercise

Engaging several of the systems listed above could be considered exercise, even perhaps playing chess which requires plenty of resources and can become very competitive may be considered an exercise but that is broadly speaking. There are different types of exercises and they can be combined, mixed and it could be argued that the person ought to find one or several that works for them.

There are several types of exercise, including:

1. Cardiovascular exercise: Also known as cardio, this type of exercise involves activities that increase your heart rate and breathing, such as running, cycling, swimming, and dancing.
2. Resistance training: This type of exercise involves working against some type of resistance to build strength and muscle mass. Examples include weightlifting, bodyweight exercises like push-ups and squats, and resistance band exercises.
3. Stretching and flexibility exercises: Stretching helps to improve flexibility, range of motion, and balance. Yoga and Pilates are two examples of stretching and flexibility exercises.
4. High-Intensity Interval Training (HIIT): This type of exercise involves short bursts of high-intensity exercise followed by periods of rest or lower-intensity exercise. It can be done with cardio or resistance training exercises.
5. Low-Intensity Steady State (LISS): This type of exercise involves maintaining a steady state of low to moderate-intensity exercise for a longer period of time, such as walking, jogging, or cycling.
6. Functional training: This type of exercise focuses on improving movements and activities of daily living, such as lifting groceries or climbing stairs. Examples include bodyweight exercises, resistance band exercises, and kettlebell workouts.
7. Mind-body exercises: These exercises aim to improve the mind-body connection, such as yoga, tai chi, and qigong. They typically involve slow movements and breathing techniques.
8. Mind exercises: These typically involve intense thinking, and competing, and whilst not strictly speaking an exercise, the body may tense up, and the hormones released could be similar to that of exercise.
9. Exercise-mimicking activity: Exercise-mimicking activities such as exposure to cold or hot temperatures, such as taking a hot bath or a sauna when it is hot temperature and dipping in ice-cold water have a similar effect on the body as exercise, and could be included as subtype of exercise.

Overall, incorporating a variety of exercises into your routine can help to improve your overall fitness and prevent boredom. It’s also important to find activities that you enjoy and that fit into your lifestyle.

Exercise and aging

In short of course, exercise improves our health, all aspects of it.

If we could bottle the effects of exercise, we’d win the nobel prize

Scientists

What the body has for energy

The human body stores energy in the form of several molecules, including:

1. ATP (adenosine triphosphate): This is the primary energy carrier in the body. ATP is produced by the mitochondria in cells through a process called cellular respiration, which converts nutrients such as glucose into energy. When energy is required for cellular processes, ATP is broken down into ADP (adenosine diphosphate) and phosphate, releasing energy that can be used by the body.
2. Glycogen: This is a complex carbohydrate that is stored in the liver and muscles. It is a stored form of glucose and can be quickly broken down into glucose when energy is needed.
3. Triglycerides: These are the main storage form of fat in the body. They are stored in adipose tissue and can be broken down into fatty acids and glycerol to provide energy for the body.
4. Creatine phosphate: This is a molecule that is stored in muscle cells and can be rapidly converted into ATP to provide energy for muscle contractions.

Overall, the human body stores energy in various forms, and these energy stores are used to power different physiological processes. The body’s ability to store and use energy is essential for survival and the performance of physical activities.

How is the energy consumed and in what order

When the body needs energy, it typically utilizes these energy sources in the following sequence:

1. Creatine phosphate: The body first utilizes the stored creatine phosphate to provide energy for short bursts of intense activity, such as sprinting or weightlifting. Creatine phosphate can provide energy quickly, but it is also depleted rapidly.
2. ATP: Once the creatine phosphate stores are depleted, the body turns to ATP to provide energy. ATP is continually produced by the body through cellular respiration, but its supply is limited. As the body uses ATP, it is broken down into ADP and phosphate, and the energy released is used to power cellular processes.
3. Glycogen: If the body requires energy for prolonged activity, it will break down glycogen into glucose, which can be used to produce more ATP through cellular respiration. The liver releases glucose into the bloodstream, while muscles use the stored glycogen to produce ATP for energy.
4. Triglycerides: If the body requires energy for even longer periods, it will break down triglycerides in adipose tissue to produce energy. The breakdown of triglycerides releases fatty acids, which are used to produce ATP through a process called beta-oxidation.

Overall, the body utilizes these energy sources in a coordinated and sequential manner, depending on the energy demands placed on it.

Which systems are involved in energy usage

During exercise, the body uses different energy systems to produce the energy required for muscle contraction. The three main energy systems involved in exercise are the phosphagen system, the anaerobic system, and the aerobic system. Here’s a brief overview of each system:

1. Phosphagen system: The phosphagen system is the primary energy system used during short-duration, high-intensity activities such as weightlifting, sprinting, and jumping. This system relies on stored ATP (adenosine triphosphate) and creatine phosphate (CP) to produce energy quickly. When ATP is broken down, it releases energy and becomes ADP (adenosine diphosphate). Creatine phosphate then donates a phosphate group to ADP, regenerating ATP. This process is very rapid and can produce energy for up to 10 seconds of high-intensity exercise.
2. Anaerobic system: The anaerobic system is used during high-intensity exercise that lasts longer than 10 seconds but less than 2 minutes. This system relies on stored glycogen to produce energy through a process called glycolysis, which breaks down glucose into pyruvate. This process does not require oxygen and can produce energy quickly, but it also produces lactic acid, which can lead to muscle fatigue and discomfort. The anaerobic system can provide energy for up to 2 minutes of high-intensity exercise.
3. Aerobic system: The aerobic system is used during low to moderate intensity exercise that lasts longer than 2 minutes. This system relies on oxygen to produce energy through a process called oxidative phosphorylation, which breaks down glucose, glycogen, and fatty acids to produce ATP. The aerobic system is slower to produce energy than the other two systems, but it is more efficient and can produce energy for prolonged periods of exercise.

Powering through that feeling of discomfort

When transitioning from the anaerobic to the aerobic energy system during exercise, there is a period of discomfort and fatigue as the body adjusts to the shift in energy production. However, once the transition is made, the body becomes more efficient at using oxygen and producing energy through the aerobic system. This can lead to a decrease in the feeling of discomfort and an increase in the ability to sustain the exercise for longer periods of time.

This transition is often referred to as the “second wind” or “runner’s high” and is characterized by a feeling of increased energy and reduced discomfort during aerobic exercise. This is due to the release of endorphins and other feel-good chemicals in the brain, as well as the body’s increased efficiency at using oxygen and producing energy through the aerobic system.

However, it’s important to note that pushing through discomfort and fatigue during exercise can also lead to injury and overexertion. It’s important to listen to your body and gradually build up your fitness level to avoid injury and fatigue.