Module 9 Flashcards
Fitness
• Definition: – Ability to perform routine physical activity without undue fatigue • Overload Principle – Body will adapt to stresses placed on it • Parameters – Cardiorespiratory Endurance – Muscle Strength and Endurance – Flexibility – Healthy Body Composition
Cardiorespiratory Endurance
• Determines how long one can continue a task with an
elevated heart rate
– Requires muscle strength
– Involves
• Cardiovascular system
• Respiratory system
• Endurance is increased by aerobic exercise (any exercise that
increases heart rate and requires oxygen in metabolism)
– Increases stroke volume decreases resting heart rate
– More fit people have slower resting heart rates
Cardiorespiratory Endurance
Increases maximal oxygen consumption • Depends on – Body’s ability to deliver oxygen to cells – Cells’ ability to use oxygen to produce energy • Aerobic capacity, VO2 max, is the body’s ability to generate ATP by aerobic metabolism during exercise • The greater the VO2 max the more intense an activity the person can engage in before lack of O2 affects performance
Health Benefits of Exercise
• Maintenance of a healthy body weight – Increase lean tissue and limit body fat – More lean tissue keeps energy needs high • Reduces risk of cardiovascular disease – Strengthens heart – Lowers blood pressure – Increases HDL cholesterol • Reduces risk of Type II Diabetes – Improves insulin sensitivity
Health Benefits of Exercise (Cont.)
• Reduces risk of Osteoporosis and Joint Disorders
– Weight-bearing exercise can increase bone mass and
reduce bone loss
– Exercise can benefit those with arthritis by increasing
strength and flexibility
• Reduces risk of some cancers
– Breast and colon
• Mood Elevation
– Release of endorphins
ATP (energy source)
– The immediate source of energy for all body functions
– Small amounts stored in muscle
Creatine Phosphate (Energy Source)
– A compound found in muscle that can be broken down
to generate ATP
ATP is used for energy during exercise in…
– In resting muscle, there is enough ATP to
sustain an intense activity for a few seconds
– Creatine Phosphate is sort of a “back-up”
supply of energy to make ATP in muscle
• Enough to fuel 10-15 seconds of exercise
ATP needs to be replenished from:
– Fat, carbohydrate, and protein metabolism
– Through electron transport chain
Availability of Oxygen
– If oxygen is available, fat, carbohydrates, and protein can all be burned for energy •Aerobic metabolism – If oxygen is unavailable, then only carbohydrates can be used for energy •i.e. Anaerobic metabolism
Energy usage for slow exercise:
• If you are exercising slowly enough that you have
oxygen to run electron transport chain:
– You are using primarily fatty acids for energy
Energy Usage for Intense exercise
• If you are exercising so intensely that the body or
specific muscles cannot get enough oxygen to run
electron transport chain:
– You are using glucose through glycolysis
– Producing lactic acid as a by-product
Fat as an Energy Source
• Fatty acids must be transported into mitochondria to be
burned
– Requires the molecule carnitine
– Carnitine supplements marketed to athletes
Carnitine
• Carnitine is made by the body from amino acids
– Does not need to be eaten
– No evidence that healthy people…
• Burn more fat with carnitine supplements
• Have better endurance with supplements
Effect of Training
• Training results in physiological changes that
allow you to better burn fat for energy
– Can go longer without switching to glycogen
(limited supply)
•More blood delivered with each beat
•Increased capillary vessels to muscles
•Increased number of muscle cell
mitochondria
• Increased ability to store muscle glycogen
Energy needs are affected by
– BMR, TEF and PA
