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Powerhouse of the Cell
As mentioned in the previous video, an important change that occurs in your body when you exercise affects mitochondria (my-toh-KON-dree-uh)—tiny structures deep inside your cells. Mitochondria are organelles, or parts of a cell that perform a particular function. Through a process called respiration, mitochondria turn fats and carbohydrates from the food you eat into energy your body can use. This animation shows in detail where mitochondria exist inside a muscle cell.
Click on the left to watch the video.
As you exercise, mitochondria increase in number, grow larger, and make more energy. This means you can run, cycle, or swim faster and longer. But these additional mitochondria need additional oxygen for respiration to occur. Here's how they get it:
All of these actions strengthen your muscles, heart, and lungs and improve the way your body works.