For example, you burn calories when you walk, swim, sleep, read and breathe. Dehydration is the condition that occurs from a loss in body water. The main cause of dehydration during activity is an increase in sweat production without adequate fluid intake. The greatest risk for dehydration occurs when you exercise in the heat. To learn more about fluid replacement, visit the Nutrition Center.
Fitness is a general term with many meanings.
In general, physical fitness is the ability to do daily activities without feeling overly tired. Physical fitness has four parts. Cardiovascular and respiratory fitness reflects the condition of your heart and lungs, and the ability of your body to deliver oxygen throughout the body. Muscular fitness means the strength and endurance of your muscles. Flexibility is the ability to move your joints freely and without pain.