Фрагмент из книги:
Scientists say that people should do one hour of physical activity every day. It can be sports, exercise or everyday activities, such as walking. In the USA, only 25% of teenagers do enough physical activity, and that’s a problem. In addition, teens need three types of training to keep fit: weight, aerobic and flexibility training. They also need to train well for specific sports. Good coaches understand athletes' needs and help them to train properly.








