Health Sci: Chapter 6
- When the body is left unchallenged, bones lose their density, joints stiffen, muscles
become weak, and cellular energy systems begin to degenerate. Humans must be
What is Physical Fitness?
- The body’s ability to respond or adapt to the demands and stress of physical effort:
to perform moderate to vigorous levels of physical activity without becoming overly
- Health Related fitness include the following components:
- Heather related fitness helps you withstand physical challenges and protects you
- The ability to perform prolonged, large muscle, dynamic exercise at moderate to
- Depends on factors like the lungs ability to deliver oxygen to the bloodstream, the
hearts capacity to pump blood, the ability of the nervous system and blood vessels
to regulate blood flow, and the body’s ability to use oxygen and process fuels for
- Poor cardio endurance is linked to heart disease, diabetes, colon cancer, stroke,
depression, and anxiety.
- Endurance training conditions the heart, making it stronger and improving the
entire cardiorespiratory system. Also improves the function of the body’s chemical
Heart to pump more blood per heartbeat
Resting heart rate to slow and resting blood pressure to decrease
Blood volume increases
Blood supply to tissue improves
The body can cool itself better
- Less than 50% of kids take physical education after grade 9.
- The amount of force a muscle can produce with a single maximum effort.
- Depends on the size of the muscle cells and the ability of nerves to activate muscle
- Older people tend to lose muscle mass (called sarcopenia), and many of the
remaining muscles become nonfunctional because they lose attachment to their
nervous system. Muscular Endurance
- The ability to resist fatigue and sustain a given level of muscle tension – to hold
muscle contraction for a long time or to contract a muscle over and over again.
- Depends of the size of the muscle cell, the ability of muscles to store fuel, ad the
blood supply to muscles.
- The ability to move joints through their full range of motion.
- Depends on joint structure, the length and elasticity of connective tissue, and
nervous system activity.
- Refers to the proportion of fat and fat-free mass (muscle, bone, water) in the body.;
the non-fat component of the body.
- A person with excessive body fat – especially in the abdominal region – is more
likely to experience health problems, including heart disease, high blood pressure,
stroke, joint problems, diabetes, gallbladder disease, cancer, and back pain.
Skill Related Components of Fitness
- The ability to perform a specific sport or activity may depend on skill-related
fitness components including:
Speed: the ability to perform movement in a short time
Power: ability to exert force rapidly, combination of strength and speed
Agility: ability to change body’s position quickly and accurately
Balance: ability to maintain equilibrium while either moving or stationary
Coordination: ability to perform motor tasks accurately and smoothly by
using body movements and the senses.
Reaction Time: ability to respond quickly to a stimulus
- Sport specific and developed through practice.
- Physical inactivity contributes to more than 21,000 premature deaths in Canada
each year and about $1.6 billion in direct costs
Physical Activity and Exercise For Heath and Fitness
- At all ages, Canadian males are more active than females, with less than half the
population being active enough to trigger health gains.
- Levels have decreased over the last 3 decades
- 88% of youth do not get the recommended amount of physical activity every day.
- Differences also exist among different ethnic groups when it comes to meeting
guidelines for moderate physical activity: White and Aboriginal people are most like
to be moderately active, while Black, West Asian and South Asian, and Arab people
are least likely to be sufficiently active. Physical Activity on a Continuum
- Physical activity = any body movement carried out by the skeletal muscles and
requiring energy. Can be based on a continuum depending on the amount of energy
- Exercise refers to a subset of physical activity – planned, structured, repetitive
movement of the body intended specifically to improve or maintain physical fitness.
- Physical activity is essential to health and confers widely ranging health benefits,
but exercise is necessary to significantly improve physical fitness.
Increasing Physical Activity to Improve Health and Wellness
- In 1998, Health Canada and the Canadian Society for Exercise Physiology (CSEP)
launched Canada’s Physical Activity Guide to Healthy Active Living.
- Indicated that Canadians were unaware that physical inactivity is a serious risk
factor for premature death, chronic disease, and disability, with a magnitude of risk
and comparable risk of smoking.
- 2/3’s of Canadians were inactive.
- In 2011, CSEP related new guidelines with the support of the Public Health Agency
- 18-64 year olds recommended to do strength-training activities at least 2 days per
week, and moderate-intensity to vigorous aerobic activity more days per week. Each
session should be at least 10 minutes, and adults should have 150 minutes a week.
Increasing Physical Activity to Manage Weight
- Guidelines focusing on weight management have also been created
- Call for more daily physical activity than the guidelines designed for general health
- Do not conflict with CSEP, but have different emphasis.
- They said 150 minutes a week might not be enough for some people, and 45-90
minutes a day is recommended.
Exercising to Improve Physical Fitness
- People can obtain even greater health and wellness benefits by increasing the
duration and intensity of physical activity.
(Chart on pg. 183)
How Much Physical Activity is Enough?
- Depends on the individual’s health status and goals.
- Other researchers suggest that people should exercise long enough and intensely
enough to improve their body’s capacity for exercise – that is – to improve physical
The Benefits of Exercise
Improved Cardiorespiratory Functioning
- During exercise, the cardiorespiratory system must work harder to meet the
body’s increased demand for oxygen. Regular endurance exercise improves the
functioning of the heart and the ability of the cardio system to carry oxygen to body tissues. Exercise directly affects the health of your arteries, sexual function, and
More Efficient Metabolism
- Endurance exercise improves metabolism, the process that converts food to energy
and builds tissue.
- Process involves oxygen, nutrients, hormones, and enzymes.
- A physically fit person can more efficiently generate energy use carbs and fat for
energy, and regulate hormones. May also protect cells from damage by free radicals,
and from inflammation cause by high blood pressure or cholesterol, nicotine and
overeating. Training activates antioxidant enzymes that prevent free radical damage
Improved Body Composition
- Healthy body composition means that the body has a high proportion of fat-free
mass, and a relatively small proportion of fat.
- 33% of Canadians who were at healthy weight in 1995 were overweight by 2003.
- Endurance exercise significantly increases daily calorie expenditure it also slight
raises metabolic rate, the rate at which the body burns calories, for several hours
Disease Prevention and Management
- Regular physical activity lowers your risk of many chronic, disabling diseases
- Six major risk factors for CVD = sedentary lifestyle, smoking, abnormal blood clots,
high blood pressure, diabetes, obesity.
- Risk factors linked by a group of symptoms called metabolic syndrome. These
symptoms include insulin resistance, high blood pressure, abnormal blood fats,
abdominal fat deposits, type 2 diabetes, blood clotting abnormalities, and blood
- Physical inactivity increases the risk of CVD by 50-240%
- Directly interferes with the disease process itself, directly lowering risk of heart
disease and stroke:
Blood Fat Levels: endurance training and strength training have a positive
effect on the balance of lipids that circulate in the blood.
High Blood Pressure: Endurance exercise tends to reduce high blood
pressure (hypertension), a contributing factor to many diseases.
Coronary Heart Disease: involves blockage of one of the coronary arteries.
Theses blood vessels supply the heart with oxygenated blood, and an
obstruction in one of them can cause a heart attack. Exercise interferes with
Stroke: occurs when a blood vessel leading to the brain is blocked or
ruptures, often through the same disease process that leads to heart attacks.
Regular exercise reduces the risk of stroke Cancer
- Link between physical activity and risk of cancer, but no conclusive studies.
- Colon cancer, and possible breast and reproductive cancer in women and prostate
- Possible also reduces risk for pancreatic cancer.
- Benefit of exercise, especially for women.
- A disease that results in loss of bone density and poor bone strength.
- Too much exercise can depress levels of estrogen, which helps maintain bone
density, thereby leading to bone loss, even in young women.
Type 2 Diabetes
- People with this are prone to heart disease, blindness, severe problems of the
nervous and circulatory systems.
- Exercise prevents the development of type 2 diabetes, the most common form of
- Exercise burns excess sugar and makes cells more sensitive to insulin.
- Diabetes is a contributing factor in more than 41,000 Canadian deaths a year.
Improved Psychological and Emotional Wellness
- People who are physically active experience many social, psychological, and
emotional benefits, including:
Reduced Stress In response to stressors, physically fit people experience
milder physical responses and less emotional distress than sedentary
Reduced Anxiety and Depression Sedentary adults are more likely to feel
fatigue and depression than those who are physically active.
Improved Self-Image Performing physical activities provides proof of skill
and self-control, thus enhancing your self-concept. Exercise boosts self-
efficacy, self-confidence, and body image.
Learning and memory Exercise enhances the formation and survival of
new nerve cells and the connections between nerves, which in turn improve
memory and learning.
Enjoyment Exercise is fun. It offers a way to interact with other people, as
well as opportunities to strive and excel.
Improved Immune Function
- Exercise can have either positive or negative effects on the immune system, the
physiological processes that protect us from disease.
- Moderate endurance exercise boosts immune system, whereas excessive training
depresses it. Prevention of Injuries and Low-Back Pain
- Increased muscle strength provides protection against injury because it helps
people maintain good posture and appropriate body mechanics when carrying out
Improved Wellness for Life
- Although people differ in the maximum levels of fitness they can achieve through
exercise, the wellness benefits of exercise are available to everyone.
- Exercising can help you live a longer and healthier life.
Designing Your Exercise