1. Most of us know that physical activity leads to better health. That is nothing new. But the United States government has changed its guidance on how much exercise people need to stay healthy and when they should start. Experts say getting or attaining the health benefits from exercise may be easier than earlier thoughts.
For children and teens
Children as young as 3 years old need to be physically active. From birth to age 5, a child's brain develops more than at any other time in life. The development has a lasting effect on a child's ability to learn and to succeed in school and in life. Boys and girls in this age group need at least 3 hours of activity every day. That can be light activities, or moderate (适度的) activities. But it is not suggested to put your 5-year-old children on a "running machine" or other exercise facilities.
Children aged between 6 and 17 get at least an hour of moderate to vigorous activity a day. The activity should be aerobic (有氧的)exercise,such as biking,swimniing and running. Aerobic activity can strengthen the heart and lungs by making them work hard for several minutes or more. Exercise should also include muscle- and bone-strengthening activities, such as climbing trees, using playground equipment and playing sports. Experts suggest that children get this kind of exercise at least three times a week.
For adults
For adults, experts recommend 150 minutes per week of moderate to vigorous physical activity. That can be quick walking; that can be cutting the grass; that can be gardening; that can he dancing... any kind of activity that gets your heart rate up and gets you exercising moderately. They also think adults need at least two days of muscle-strengthening exercise like push-ups or lifting weights.
For adults over 65
For older adults, experts suggest 30 to 60 minutes per day of moderate physical activity including activities that help aid balance and flexibility. Better balance means fewer falls and less chance of injury.
1.According to the guidance, which group may spend the longest time in exercising?
A.Children aged 4.
B.Teenagers aged 15.
C.Adults aged 35.
D.Adults aged 70.
2.How many activities are suggested to adults in the text?
A.4.
B.5.
C.6.
D.7.
3.What is the purpose of the text?
A.To persuade people of all ages to exercise.
B.To inform people of the proper amount of exercise.
C.To advise people to take up aerobic exercise.
D.To stress the benefits of physical exercise
