Chapter 15, Section 2

ObjectivesDefine anaerobic exercise, and describe its

main effects on the bodyExplain how anaerobic exercise can produce

muscle fatigue and an oxygen debtDefine aerobic exercise and its main effects

on the bodyName two ways that exercise can change

body compositionDescribe an exercise plan that can lead to

physical fitness

Key TermsPhysical fitnessAnaerobic exerciseMuscle fatigueOxygen debtAerobic exerciseEnduranceFlexibility

Physical FitnessHaving a heart, lungs, and skeletal muscles

that are strong and work efficientlyMaintaining an appropriate weight for your

height and buildHaving a body that is flexible and able to

endure prolonged physical activity

A Regular Exercise ProgramExercise 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 exerciseAerobic and anaerobic

Anaerobic ExerciseThe body requires energy at different ratesShort 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 ExerciseOnly about 2% of the energy in food can be

converted in this wayThe reactions can only last for about 30 - 60

seconds.These exercises increase the size and

strength of skeletal musclesThis type of exercise causes muscle cells to

become thicker and stronger

Anaerobic ExerciseTraining 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 ExerciseA slower, steadier form of exerciseIt is more efficient than anaerobic exercise,

50% versus 2% of food energy is usedThis is due to the food molecules being

broken down in the presence of oxygenThis type of exercise strengthens the heart,

(cardiac muscles), and increases your endurance

Aerobic ExerciseThe benefits

Strengthens and increases the size of the heartA larger and stronger heart increases blood

flowThe heart has to beat less, (50 versus 70 bpm)Reduces the risk of heart disease and stroke

New Exercise ProgramsBegin slowly, adding variety a little at a timeUsing 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

SummaryAnaerobic 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

DefinitionsPhysical 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

DefinitionsOxygen 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