A.3.2.1 Active lifestyle and physical well-being Notes

An Active Lifestyle Supports Physical Well-Being

1. Physical activity plays a crucial role in maintaining overall health by improving cardiovascular fitness, muscular strength, flexibility, and mental well-being.
2. An active lifestyle helps reduce the risk of chronic diseases, obesity, and mental health disorders while enhancing overall quality of life and longevity.

Engaging in consistent exercise leads to multiple physiological and psychological benefits, such as:

1. Cardiovascular Benefits: Stronger heart muscle, improved circulation, and reduced risk of heart disease and hypertension.
2. Muscular Benefits: Increased muscle strength, endurance, flexibility, and reduced risk of sarcopenia (age-related muscle loss).
3. Skeletal Benefits: Improved bone density, reduced risk of osteoporosis, and better joint mobility.
4. Metabolic Benefits: Enhanced glucose metabolism, lower risk of obesity, and better weight regulation.
5. Immune System Benefits: Reduced inflammation, improved immune response, and lower susceptibility to infections.
6. Mental Health Benefits: Lower stress levels, reduced risk of depression and anxiety, and improved cognitive function.

Factors Influencing a Healthy Level of Physical Activity

1. Age

The body's capacity for exercise changes with age due to growth, development, and aging processes. Different age groups have distinct activity requirements and physiological considerations.

Children and Adolescents (0–18 years)

1. Require high energy levels for growth and development.
2. Engage in spontaneous movement (e.g., running, climbing, playing sports).
3. Benefit from activities that promote motor skill development, strength, and coordination.
4. Recommended: At least 60 minutes of moderate to vigorous physical activity daily.

Adults (19–64 years)

1. Experience slower metabolism compared to children.
2. Engage in work-related and leisure activities that influence fitness levels.
3. Require regular physical activity to maintain cardiovascular health, muscle tone, and weight.

Older Adults (65+ years)

1. Experience decreased muscle mass, bone density, and joint flexibility.
2. Benefit from low-impact activities (e.g., walking, swimming, yoga) that prevent falls and improve balance.
3. Physical activity helps reduce the risk of osteoporosis, arthritis, and cardiovascular diseases.

2. Sex Differences

1. Biological differences between males and females influence physical activity levels, energy expenditure, and athletic performance.
2. These differences arise due to hormonal variations, muscle composition, and fat distribution.

Males (Higher Testosterone Levels)

1. More muscle mass and lower body fat percentage than females.
2. Higher VO₂ max (aerobic capacity) due to larger heart and lungs.
3. Greater muscle strength and power, leading to higher energy expenditure.

Females (Higher Estrogen Levels)

1. More fat storage in hips and thighs, supporting reproductive functions.
2. Hormonal fluctuations affect metabolism and exercise performance.
3. Menstrual cycle phases impact endurance, recovery, and energy metabolism.

3. Lifestyle and Socio-Economic Factors

Lifestyle Choices and Daily Activity

Modern lifestyles often contribute to sedentary behaviors, particularly in urban settings.

1. Sedentary Jobs (e.g., Office Work) → Lower daily energy expenditure.
2. Active Professions (e.g., Construction Workers, Athletes) → Higher physical activity levels.

Socio-Economic Status (SES) and Access to Physical Activity

1. Higher SES groups often have access to gyms, trainers, and healthy food choices.
2. Lower SES groups may engage in manual labor, but lack structured exercise opportunities.

Energy Balance

Energy balance is crucial in determining whether the body is in a state of maintenance, weight loss, or weight gain.

1. Positive Energy Balance: Occurs when energy intake exceeds energy expenditure, leading to weight gain.
2. Negative Energy Balance: Occurs when energy expenditure exceeds energy intake, leading to weight loss.
3. Energy Equilibrium: Occurs when energy intake equals energy expenditure, leading to stable weight.

Energy Intake

Energy intake refers to the calories consumed from food and drink.

1. Carbohydrates (4 kcal/g)

1. Carbohydrates are the primary energy source for high-intensity exercise.
2. Carbs are metabolized into glucose, the body's preferred fuel during activity.
3. Excess glucose is stored as glycogen in the muscles and liver for later use.
   1. Simple carbohydrates (e.g., sugars, fructose) provide quick energy and are found in foods like fruits, dairy, and processed foods.
   2. Complex carbohydrates (e.g., starches, fiber) provide longer-lasting energy and are found in foods like whole grains, legumes, and vegetables.

2. Proteins (4 kcal/g)

1. Proteins are mainly used for muscle repair and growth, but they can also be used as an energy source when carbohydrate intake is insufficient.
2. Proteins are broken down into amino acids, which play a vital role in building and maintaining muscle tissue and other cellular functions.
3. Sources include meat, eggs, dairy products, and plant-based proteins (e.g., beans, legumes, quinoa).

3. Fats (9 kcal/g)

1. Fats provide the highest energy density and are essential for long-term energy storage.
2. Fat is utilized primarily during low-intensity or endurance activities.
3. Fats also help with the absorption of fat-soluble vitamins (A, D, E, K) and provide insulation and protection to organs.
4. Sources include healthy fats (e.g., olive oil, avocado, fatty fish) and saturated fats (e.g., animal fats, butter).

Muscular System

Positive Effects of Exercise on the Muscular System

Regular physical activity has a profound impact on muscle function, including the following positive effects:

Muscle Strength

1. Muscle strength refers to the ability of a muscle or group of muscles to exert force against resistance.
2. Regular resistance training and weight-bearing exercises (such as lifting weights) stimulate muscle fibers, leading to increased strength.

Muscle Endurance

1. Muscle endurance is the ability of a muscle to perform repeated contractions over an extended period without fatigue.
2. Exercises such as running, cycling, and swimming enhance endurance by improving the oxidative capacity of muscle fibers.

Muscle Hypertrophy

1. When muscles are exposed to resistance or stress, such as lifting heavy weights, they adapt by increasing in size.
2. This is the result of muscle fiber repair after microscopic damage incurred during exercise.
3. Hypertrophy is most effectively achieved with moderate to high resistance and repetitions (typically 6-12 reps per set).

Negative Effects of Exercise on the Muscular System

While regular physical activity brings numerous benefits, improper or excessive exercise can lead to negative consequences for the muscular system:

Overtraining

1. Overtraining occurs when an individual exceeds the body’s ability to recover from intense physical activity.
2. This can lead to muscle breakdown, fatigue, and a decrease in performance. Signs include persistent soreness, reduced strength, and poor sleep.

Muscle Fatigue

This happens when the body’s energy stores (such as glycogen) are depleted, leading to muscle exhaustion and a decline in performance.

Muscle Injuries

1. Muscle injuries such as strains, tears, or sprains are common, especially when exercise is done improperly or without a warm-up.
2. Overuse injuries, such as tendinitis, are common in athletes who perform repetitive movements.

Immune System

Positive Effects of Exercise on the Immune System

Exercise has significant benefits for immune function, particularly when performed in moderation.

Enhanced Circulation of Immune Cells

1. Regular moderate physical activity boosts immune system function by improving the circulation of immune cells such as T-cells, B cells and macrophages, which play a crucial role in fighting infections.
2. Exercise increases blood flow, helping immune cells travel through the body more efficiently to detect and combat pathogens.

Reduction in Chronic Inflammation

1. Chronic low-level inflammation has been linked to conditions such as cardiovascular diseases, diabetes, and arthritis.
2. Exercise helps to reduce chronic inflammation, a key factor in the development of many diseases.
3. Regular moderate physical activity can decrease the production of pro-inflammatory cytokines and increase anti-inflammatory cytokines, improving overall immune function.

Improved Immune Responses

1. Moderate exercise enhances the overall responsiveness of the immune system.
2. Exercise increases the production of antibodies and enhances the activity of macrophages, which are important in detecting and destroying pathogens.

Negative Effects of Exercise on the Immune System

Excessive or intense exercise without adequate recovery can negatively impact the immune system, leading to an increased risk of infections and illness.

Suppressed Immunity from Intense Exercise

1. Intense or prolonged exercise (e.g., marathon running, long-distance cycling) can lead to immune suppression.
2. This is particularly true when recovery time is insufficient.
3. During periods of intense exercise, the body’s stress hormones, like cortisol, are elevated, which can suppress the activity of immune cells.

Increased Susceptibility to Infections

1. Athletes who engage in excessive training or competition without adequate recovery often experience a period of immune suppression.
2. This is why athletes are more prone to upper respiratory tract infections (URTIs), such as the common cold, after periods of intense training.

Chronic Stress and Immune Function

1. Chronic stress from overtraining can impair immune function by increasing levels of cortisol, a hormone that suppresses immune responses.
2. When cortisol remains elevated for extended periods, it can reduce the number of immune cells available to fight off infections.

The J-Shaped Curve

1. The J-shaped curve illustrates the relationship between physical activity and the incidence of upper respiratory tract infections (URTI), such as the common cold, sinus infections, and other upper respiratory illnesses.
2. It shows that exercise has both beneficial and detrimental effects on immune function depending on its intensity and volume.
3. At low levels of exercise, individuals may not stimulate their immune system enough.
4. Conversely, at high volumes of exercise, such as intense training, the immune system can become suppressed, increasing the risk of infections.
   1. Moderate Exercise: Involves regular physical activity that is neither too intense nor too light, such as jogging or swimming, which boosts immune function.
   2. Excessive Exercise: Involves training that is prolonged or highly intense, such as long-distance running or extreme endurance activities, which may lead to immune suppression.

Low to Moderate Exercise: Enhancing Immune Function

Positive Effects on Immunity

1. Low to moderate exercise enhances immune function by stimulating the circulation of immune cells, such as T-cells and macrophages.
2. This helps the body fight infections more effectively.

Chronic Inflammation Reduction

1. Regular exercise also helps to reduce chronic inflammation, which has been linked to numerous health problems, including cardiovascular diseases and autoimmune disorders.
2. This is achieved by the body's production of anti-inflammatory cytokines during moderate physical activity.

High Exercise Volume (Excessive Exercise)

Negative Impact on Immunity

Prolonged or intense physical activity (e.g., long-distance running, excessive endurance training) can negatively affect the immune system.

Cortisol and Immune Suppression

1. Excessive training increases cortisol levels (a stress hormone), which has a suppressive effect on the immune system by reducing the efficiency of immune cells like T-cells and B-cells.
2. This leads to a temporary period of weakened immunity.

The U-Shaped Curve of Exercise and Immunity

The J-shaped curve suggests that a sedentary lifestyle is as detrimental as excessive exercise when it comes to immune health.

1. Sedentary Individuals: A lack of exercise leads to poor circulation, lower immune function, and an increased risk of infections.
2. Moderate Exercise: Offers protection against infections by promoting regular immune system activity.
3. Excessive Exercise: Increases vulnerability to URTIs, as chronic overtraining leads to immune suppression.

Maintaining Immune Health in Athletes

To optimize immune health and minimize the risk of infections, athletes must incorporate strategies that balance training, nutrition, rest, and stress management.

Balanced Training

1. Athletes should incorporate periods of rest and recovery into their training schedule.
2. These periods allow the immune system to recover from the strain of exercise, preventing overtraining and immune suppression.
3. When the body is not allowed adequate recovery time, immune cells like T-cells and B-cells become less effective at responding to infections.
4. Rest periods allow these immune cells to regenerate and function at optimal levels.

Nutrition

Adequate intake of macronutrients (proteins, fats, carbohydrates) and micronutrients (vitamins and minerals) is essential for maintaining immune function.

1. Protein: Crucial for tissue repair and the production of antibodies and cytokines, which help fight infections.
2. Carbohydrates: Provide energy for sustained activity. Adequate carb intake helps prevent immune suppression during prolonged exercise.
3. Fats: Healthy fats, particularly omega-3 fatty acids, have anti-inflammatory effects and help support immune function.
4. Vitamins such as Vitamin C, Vitamin D, and zinc are essential for immune health.

Sleep

1. Sufficient, quality sleep is crucial for immune function.
2. During sleep, the body produces immune cells such as T-cells, which help combat infections.
3. Sleep deprivation can lead to lower levels of immune cells and increased inflammation, making the body more susceptible to infections.