Transcript Exercise and Physical Fitness

Chapter 15, Section 2
Objectives
 Define anaerobic exercise, and describe its main
effects on the body
 Explain how anaerobic exercise can produce muscle
fatigue and an oxygen debt
 Define aerobic exercise and its main effects on the
body
 Name two ways that exercise can change body
composition
 Describe an exercise plan that can lead to physical
fitness
Key Terms
 Physical fitness
 Anaerobic exercise
 Muscle fatigue
 Oxygen debt
 Aerobic exercise
 Endurance
 Flexibility
Physical Fitness
 Having a heart, lungs, and skeletal muscles that are
strong and work efficiently
 Maintaining an appropriate weight for your height and
build
 Having a body that is flexible and able to endure
prolonged physical activity
A Regular Exercise Program
 Exercise involves any physical activity that requires
your body to do work and uses energy
 The energy is obtained from the foods you eat
 Oxygen reacting with carbohydrates, fats, and proteins
in your body to release this energy
 There are two basic types of exercise
 Aerobic and anaerobic
Anaerobic Exercise
 The body requires energy at different rates
 Short or quick bursts of energy cannot wait for the
oxygen to burn the nutrients that provide the energy
 There are reactions that release energy but do not
require large amounts of oxygen
 These reactions are inefficient and create more “waste
products” than oxygen rich reactions
Anaerobic Exercise
 Only about 2% of the energy in food can be converted
in this way
 The reactions can only last for about 30 - 60 seconds.
 These exercises increase the size and strength of
skeletal muscles
 This type of exercise causes muscle cells to become
thicker and stronger
Anaerobic Exercise
 Training your muscles involves working the muscles
against a load, (weightlifting)
 One chemical reaction in this type of training converts
Glucose, (a simple sugar found in the blood), into
lactic acid, (causes soreness)
 Lactic Acid causes pain and muscle fatigue, ( a
warning to stop before injury results)
 Lactic Acid removal requires oxygen, the amount of
oxygen needed is your oxygen debt
Aerobic Exercise
 A slower, steadier form of exercise
 It is more efficient than anaerobic exercise, 50% versus
2% of food energy is used
 This is due to the food molecules being broken down
in the presence of oxygen
 This type of exercise strengthens the heart, (cardiac
muscles), and increases your endurance
Aerobic Exercise
 The benefits
 Strengthens and increases the size of the heart
 A larger and stronger heart increases blood flow
 The heart has to beat less, (50 versus 70 bpm)
 Reduces the risk of heart disease and stroke
New Exercise Programs
 Begin slowly, adding variety a little at a time
 Using Exercise
 To obtain flexibility: there are many stretching exercises
that can help ligaments, tendons and muscles become
more flexible
 To reduce body fat: converting body fat, (energy), to
muscle requires anaerobic exercise
 To develop endurance: alternate training styles from day
to day
Summary
 Anaerobic exercise is powered by chemical reactions that
do not require oxygen, It increases the size and strength of
skeletal muscles
 Aerobic exercise is powered by chemical reactions that
require oxygen, It makes the heart stronger, improves
oxygen uptake, and increases endurance
 Physical fitness increases the body’s flexibility and muscle
mass while decreasing the amount of fat
Definitions
 Physical fitness is the ability to carry out moderate
physical tasks without becoming tired
 Anaerobic exercise is an exercise that is powered by
energy releasing reactions that do not require oxygen
 Muscle fatigue is the loss of muscle strength due to
prolonged exercise
Definitions
 Oxygen debt is the extra amount of oxygen needed to
return muscles to their normal condition after
anaerobic exercise
 Aerobic exercise is an exercise that is powered by
energy releasing reactions that require oxygen
 Endurance is the ability to continue exercising before
becoming completely exhausted
 Flexibility is the ability of the body to move at its joints