9781422287019

Text-Dependent Questions 1. According to the author, what are the three keys to keeping a body healthy? 2. What is metabolism? 3. How are sports and sleep connected—and why is sleep im- portant for good health? 4. What is the connection between exercise and muscles?

The heart is made of one of the most important types of muscle in the human body—cardiac muscle—and it needs regular exercise to stay in shape. This organ is responsible for bringing oxygen and important nutrients to every cell in the body. The heart works with the lungs and skeletal muscles to keep a body in motion. Fortunately, almost everything the body does will count as some sort of movement. Walking to a friend’s house, helping out with yard work, and cleaning up the house are all very easy types of movement. They are not as intense as other exercises, but they are better than sitting on the couch all day or playing on the computer all night. Sports offer a great way to stay active. Playing sports has physical, mental, and emotional benefits. Sports connect us to others, so they’re good ways to make friends and have fun—and stay healthy!

Staying Active, Staying Healthy

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