Intensity of exercise

Intensity describes how hard you work during physical activity.

• Low-Intensity physical activities make your heart work a little harder than usual. Walking slowly and cleaning your room are low-intensity activities.
• Moderate-Intensity physical activities, such as fast walking and swimming, make your heart and muscles work harder.
• Vigorous-Intensity physical activities, include running, swimming laps, and bicycling over hills.These activities make your heart and muscles work even harder than moderate-intensity activities. Your heart rate , breathing rate , and blood preassure increase even more.

To be physically fit ,spend at least 30 minutes in moderate-intensity activities each day.You also need 30 minutes of vingorous activities at least three or four times each week.