Physical Fitness

Physical Fitness Most people can derive important health benefits by exercising regularly and becoming more physically active. Each year, lack of regular physical activity contributes to thousands of American deaths, primarily from heart disease, stroke, and diabetes. Physically fit people have the strength, endurance, and flexibility to perform daily living activities that require physical movement.

Most people can derive important health benefits by exercising regularly and becoming more physically active.

Each year, lack of regular physical activity contributes to thousands of American deaths, primarily from heart disease, stroke, and diabetes.

Physically fit people have the strength, endurance, and flexibility to perform daily living activities that require physical movement.

The Body in Motion: Musculoskeletal System Physical movement involves the functioning of the muscular and skeletal system. Skeletal muscles provide shape, support, and movement. Skeletal muscle contains hundreds of muscle cells called muscle fibers . When muscle fibers contract, they shorten, causing movement.

Physical movement involves the functioning of the muscular and skeletal system.

Skeletal muscles provide shape, support, and movement.

Skeletal muscle contains hundreds of muscle cells called muscle fibers .

When muscle fibers contract, they shorten, causing movement.

Musculoskeletal System (continued) Tendons connect muscles to bones. Joints are where bones come together. Ligaments hold bones together at the joints.

Tendons connect muscles to bones.

Joints are where bones come together.

Ligaments hold bones together at the joints.

Heart and lung function is interrelated. The heart pumps blood to the lungs. Oxygenated blood returns to the heart where it is pumped to rest of body. Oxygen leaves blood and enters cells. Waste products such as carbon dioxide leave cells and enter blood. Blood carries waste products to kidneys and back to the heart. The Body in Motion: Cardiorespiratory System

Heart and lung function is interrelated.

The heart pumps blood to the lungs.

Oxygenated blood returns to the heart where it is pumped to rest of body.

Oxygen leaves blood and enters cells.

Waste products such as carbon dioxide leave cells and enter blood.

Blood carries waste products to kidneys and back to the heart.

Physical Activity and Exercise Physical activity is movement that occurs when muscles contract. Exercise is physical activity that is usually planned and performed to improve or maintain physical condition. For example, biceps curls develop upper arm strength.

Physical activity is movement that occurs when muscles contract.

Exercise is physical activity that is usually planned and performed to improve or maintain physical condition.

For example, biceps curls develop upper arm strength.

Health Benefits of Exercise Reduces risk of chronic diseases. Heart disease, certain cancers, type 2 diabetes, hypertension, and osteoporosis Reduces risk of obesity. Improves immune system. Improves and maintains muscle strength and joint function. Improves balance. Reduces risk of premature death.

Reduces risk of chronic diseases.

Heart disease, certain cancers, type 2 diabetes, hypertension, and osteoporosis

Reduces risk of obesity.

Improves immune system.

Improves and maintains muscle strength and joint function.

Improves balance.

Reduces risk of premature death.

Health Benefits of Exercise (continued) Reduces symptoms of anxiety and depression. Fosters improvement in mood and sense of well-being. Can improve quality of sleep. Stimulates release of endorphins. May relieve stress.

Reduces symptoms of anxiety and depression.

Fosters improvement in mood and sense of well-being.

Can improve quality of sleep.

Stimulates release of endorphins.

May relieve stress.

Health-Related Components of Physical Fitness Cardiorespiratory fitness Muscular strength Muscular endurance Flexibility Body composition

Cardiorespiratory fitness

Muscular strength

Muscular endurance

Flexibility

Body composition

Cardiorespiratory Fitness Intense physical activity requires more oxygen to support the work of skeletal muscles. Individuals with high degrees of cardiorespiratory fitness, or endurance, can perform intense physical activity longer without becoming fatigued. Cardiorespiratory fitness can be developed through aerobic activities (e.g., running, swimming, rope skipping).

Intense physical activity requires more oxygen to support the work of skeletal muscles.

Individuals with high degrees of cardiorespiratory fitness, or endurance, can perform intense physical activity longer without becoming fatigued.

Cardiorespiratory fitness can be developed through aerobic activities (e.g., running, swimming, rope skipping).

Muscular Strength and Endurance Muscular strength —ability of muscles to apply maximum force against an object that is resisting that force Muscular endurance —ability to contract muscles repeatedly without becoming fatigued easily

Muscular strength —ability of muscles to apply maximum force against an object that is resisting that force

Muscular endurance —ability to contract muscles repeatedly without becoming fatigued easily

Muscular Strength Training effect To increase muscular strength, muscles need to be overloaded by moving heavy objects repeatedly. Increase weight of objects over time. Hypertrophy—muscle fibers enlarge Atrophy—muscle fibers lose size “Use it or lose it.”

Training effect

To increase muscular strength, muscles need to be overloaded by moving heavy objects repeatedly.

Increase weight of objects over time.

Hypertrophy—muscle fibers enlarge

Atrophy—muscle fibers lose size

“Use it or lose it.”

Muscular Strength: Strength Training Weight, repetitions, and sets are important. For best results, workout three times per week. Isometric exercise — applying force against a fixed object (e.g., pushing against an immovable door frame) Isotonic exercise — applying force against a movable but constant source of resistance Using barbells, push-ups, or weight machines.

Weight, repetitions, and sets are important.

For best results, workout three times per week.

Isometric exercise — applying force against a fixed object (e.g., pushing against an immovable door frame)

Isotonic exercise — applying force against a movable but constant source of resistance

Using barbells, push-ups, or weight machines.

Muscular Endurance: Flexibility Flexibility is the ability to extend muscles and joints within normal range of motion. Stretching develops flexibility, and allows people to perform certain activities with ease, such as bending, gliding, or twisting. Static stretching —slowly and fully extending muscles and joints within natural range of motion (hold for 15 seconds). Ballistic stretching (stretching with bouncing) is not recommended.

Flexibility is the ability to extend muscles and joints within normal range of motion.

Stretching develops flexibility, and allows people to perform certain activities with ease, such as bending, gliding, or twisting.

Static stretching —slowly and fully extending muscles and joints within natural range of motion (hold for 15 seconds).

Ballistic stretching (stretching with bouncing) is not recommended.

Body Composition Some fat is essential to good health. Spot exercising does not reduce fat in the exercised region. Regular exercise builds and maintains muscle mass; muscle cells burn more calories than fat cells. Exercising can increase metabolic rate. Engaging in moderate to vigorous–intensity aerobic activity for about 60 minutes, nearly every day, while not exceeding daily calorie needs, “burns” body fat.

Some fat is essential to good health.

Spot exercising does not reduce fat in the exercised region.

Regular exercise builds and maintains muscle mass; muscle cells burn more calories than fat cells.

Exercising can increase metabolic rate.

Engaging in moderate to vigorous–intensity aerobic activity for about 60 minutes, nearly every day, while not exceeding daily calorie needs, “burns” body fat.

Athletic Performance: Sports-Related Components of Fitness Speed — rate of movement Power — ability to concentrate force Coordination — ability to perform a series of movements in a continuous manner Agility — ability to make quick precise movements Balance — ability to maintain poised upright body position Reaction time — time needed to adjust body position to a changing environment

Speed — rate of movement

Power — ability to concentrate force

Coordination — ability to perform a series of movements in a continuous manner

Agility — ability to make quick precise movements

Balance — ability to maintain poised upright body position

Reaction time — time needed to adjust body position to a changing environment

Ergogenic Aids There are a variety of products that supposedly enhance physical development or performance. Dietary supplements, drugs, and mechanical devices Some are beneficial and/or harmless. Others are dangerous or illegal. Anabolic steroids

There are a variety of products that supposedly enhance physical development or performance.

Dietary supplements, drugs, and mechanical devices

Some are beneficial and/or harmless.

Others are dangerous or illegal.

Anabolic steroids

Anabolic Steroids Synthetic and natural substances chemically related to testosterone and have muscle-building properties. Often illegally obtained and abused by athletes who want to enhance muscle development and physical performance. Give individuals unfair competitive advantage over other athletes.

Synthetic and natural substances chemically related to testosterone and have muscle-building properties.

Often illegally obtained and abused by athletes who want to enhance muscle development and physical performance.

Give individuals unfair competitive advantage over other athletes.

Anabolic Steroids (continued) Adverse side effects in men include: Premature balding Severe acne Sleep disturbance Increased aggression Testicle shrinkage Increased blood pressure and increased risk of developing heart and kidney disease, certain cancers, and liver tumors

Adverse side effects in men include:

Premature balding

Severe acne

Sleep disturbance

Increased aggression

Testicle shrinkage

Increased blood pressure and increased risk of developing heart and kidney disease, certain cancers, and liver tumors

Anabolic Steroids (continued) Adverse side effects in women include: Severe acne Increased body hair, including facial hair Scalp hair loss Menstrual irregularities

Adverse side effects in women include:

Severe acne

Increased body hair, including facial hair

Scalp hair loss

Menstrual irregularities

Factors That Influence Benefits of Exercise Type of exercise Aerobic activities increase cardiorespiratory fitness and muscular endurance. Frequency Exercising at least three times a week produces more rapid overall fitness. Duration Cardiorespiratory benefits of exercise increase as the length of physical activity/exercise increases. Intensity The amount of physical exertion used during exercise increases its benefit.

Type of exercise

Aerobic activities increase cardiorespiratory fitness and muscular endurance.

Frequency

Exercising at least three times a week produces more rapid overall fitness.

Duration

Cardiorespiratory benefits of exercise increase as the length of physical activity/exercise increases.

Intensity

The amount of physical exertion used during exercise increases its benefit.

An Aerobic Workout Session Warm up — low intensity activity for 5 minutes Stretch — 5 minutes Engage in aerobic activity for 30 minutes Cool down with less intense activity for 5 minutes Stretch — 5 minutes

Warm up — low intensity activity for 5 minutes

Stretch — 5 minutes

Engage in aerobic activity for 30 minutes

Cool down with less intense activity for 5 minutes

Stretch — 5 minutes

Exercise Danger Signs Stop and consult a physician if you experience: Irregular heartbeat, sensation that heart is pounding in throat, or fluttering sensation in chest Pain or pressure in the chest, throat, or arms Shortness of breath Dizziness Sudden loss of coordination Cold sweating Fainting

Stop and consult a physician if you experience:

Irregular heartbeat, sensation that heart is pounding in throat, or fluttering sensation in chest

Pain or pressure in the chest, throat, or arms

Shortness of breath

Dizziness

Sudden loss of coordination

Cold sweating

Fainting

Preventing and Managing Common Exercise Injuries Strains and Sprains No clear clinical definitions exists. Strain generally refers to damage that a muscle or tendon sustains when overextended rapidly. Sprain usually refers to a damaged ligament. – Sprains tend to be more severe than strains.

Strains and Sprains

No clear clinical definitions exists.

Strain generally refers to damage that a muscle or tendon sustains when overextended rapidly.

Sprain usually refers to a damaged ligament.

– Sprains tend to be more severe than strains.

Managing Exercise Injuries RICE — effective for treating strains and sprains R est I ce C ompression E levation Consult a physician if injured area does not improve in 2 days or pain worsens.

RICE — effective for treating strains and sprains

R est

I ce

C ompression

E levation

Consult a physician if injured area does not improve in 2 days or pain worsens.

Temperature-Related Injuries Heat-Related Injuries Dehydration (lack of body water) Hyperthermia (higher than normal body temperature) can lead to: Heat cramps Heat exhaustion Heatstroke

Heat-Related Injuries

Dehydration (lack of body water)

Hyperthermia (higher than normal body temperature) can lead to:

Heat cramps

Heat exhaustion

Heatstroke

Preventing Temperature-Related Injuries To prevent dehydration and hyperthermia: Avoid physical exertion outdoors during hottest time of the day. Drink enough fluids to replace that which is lost through sweat. Wear light-colored, loose-fitting clothing when exercising in warm conditions.

To prevent dehydration and hyperthermia:

Avoid physical exertion outdoors during hottest time of the day.

Drink enough fluids to replace that which is lost through sweat.

Wear light-colored, loose-fitting clothing when exercising in warm conditions.

Preventing Temperature-Related Injuries (continued) Consider reducing the intensity and duration of activity when weather is hot and humid. Avoid alcoholic beverages. Caffeine does not produce major urinary losses of water.

Consider reducing the intensity and duration of activity when weather is hot and humid.

Avoid alcoholic beverages.

Caffeine does not produce major urinary losses of water.

Temperature-Related Injuries (continued) Frostbite Ice crystals form in the deeper tissues of skin when exposed to extreme cold Causes damage to tissues Hypothermia Body’s core temperature drops below 95 °F Shivering Tiredness Poor judgment Disorientation Loss of consciousness

Frostbite

Ice crystals form in the deeper tissues of skin when exposed to extreme cold

Causes damage to tissues

Hypothermia

Body’s core temperature drops below 95 °F

Shivering

Tiredness

Poor judgment

Disorientation

Loss of consciousness

Preventing Temperature-Related Injuries (continued) Preventing Hypothermia When in cold temperatures, wear: Layers of warm dry clothing A hat that can be pulled down over ears Scarf Gloves or mittens Thick socks

Preventing Hypothermia

When in cold temperatures, wear:

Layers of warm dry clothing

A hat that can be pulled down over ears

Scarf

Gloves or mittens

Thick socks

Developing a Personal Fitness Program Determine your needs, interests, and limitations. Set general fitness goals. Choose activities that you enjoy. Incorporates fitness session into your routine.

Determine your needs, interests, and limitations.

Set general fitness goals.

Choose activities that you enjoy.

Incorporates fitness session into your routine.

Across the Life Span Physical activities adopted in childhood are likely to be practiced for a lifetime. Healthy, physically fit women can generally continue engaging in mild- to moderate- intensity exercise during pregnancy. Pregnant women who perform strenuous regular exercise can increase their risk of having low-birth-weight babies. Pregnant women should discuss exercise plans with their physicians.

Physical activities adopted in childhood are likely to be practiced for a lifetime.

Healthy, physically fit women can generally continue engaging in mild- to moderate- intensity exercise during pregnancy.

Pregnant women who perform strenuous regular exercise can increase their risk of having low-birth-weight babies.

Pregnant women should discuss exercise plans with their physicians.

Across the Life Span (continued) Most Americans become less active as they age. However, it is important for people to continue exercising. Light regular physical activity can help: Reduce risk of heart disease, colon cancer, diabetes, obesity, and hypertension. Maintain or improve joint flexibility and muscle strength and endurance. Improve mood. Increase ability to live independently.

Most Americans become less active as they age.

However, it is important for people to continue exercising.

Light regular physical activity can help:

Reduce risk of heart disease, colon cancer, diabetes, obesity, and hypertension.

Maintain or improve joint flexibility and muscle strength and endurance.

Improve mood.

Increase ability to live independently.

Across the Life Span (continued) Physical activities can also be social functions. Dancing, mall walking, and fitness classes Exercise classes can improve balance and muscular strength, reducing the likelihood of falls.

Physical activities can also be social functions.

Dancing, mall walking, and fitness classes

Exercise classes can improve balance and muscular strength, reducing the likelihood of falls.