Physical activity can help protect people against obesity, heart disease and cancer, according to the Harvard School of Public Health. In the short term, physical activity is an important part of improving mood and sleep quality.
Exercise may protect the body against colon cancer and breast cancer, according to the Harvard School of Public Health. This activity also protects the body from heart disease by raising good cholesterol levels and lowering triglyceride levels, according to the Mayo Clinic. People who exercise also may maintain their body weight. Physical activity improves mental health as well. Exercise elevates the brain chemicals responsible for making people feel happier and more relaxed. When not performed close to bedtime, exercise also improves sleep quality, helping people fall asleep faster and longer.
Lack of physical activity can lead to health problems, notes the President's Council of Fitness, Sports & Nutrition. People who are not active may develop hypertension, high cholesterol, type 2 diabetes and cancer.
To benefit from physical activity, the U.S. Centers for Disease Control and Prevention recommends 150 minutes of moderate-intensity aerobic exercise, such as walking, water aerobics and gardening, each week. This can break down into 30 minutes of physical activity five days per week. The CDC also recommends at least two days of muscle-strengthening activities per week.