16. Painkilling chemicals that occur naturally in the body are known as
A. hormones.
B. triglycerides.
C. endorphins.
D. platelets.
17. Specificity is important to a fitness program because it
A. makes the workout more enjoyable.
B. allows you to choose the right types of activities to improve a particular fitness element.
C. increases the demands you place on your body.
D. helps you to exercise beyond your regular daily abilities.
18. Olympic athletes have lower resting heart rates because
A. their lungs tend to be naturally larger.
B. they have a lot of muscle mass due to weightlifting.
C. they exercise regularly, which improves the efficiency of their heart.
D. they tend to eat low-fat diets.
19. What does a measure of your cardiorespiratory endurance tell a fitness professional?
A. Your anaerobic fitness, or how well your leg and arm muscles work
B. How long you can sustain a weightlifting program
C. What type of exercises you've been doing
D. Your aerobic fitness, or how efficiently your heart is working
20. Which type of fat may help lower the risk of heart disease?
A. Saturated fat
B. Trans fat
C. Unsaturated fat
D. Cholesterol