根据短文内容填空。
Along with jogging and swimming, cycling is one of the best all-round f______ (1) of exercise.
It can help to increase your strength and e______ (2), giving you more efficient muscles (体力) and a
stronger heart. But increasing your strength is not the only a______ (3) of cycling. Because you're not
carrying the w______ (4) of your body on your feet, it's a good form of exercise for people with
p______ (5) feet or backs. However, with all forms of exercise it's important to start s______ (6)
and build up g______ (7). If you have any doubts (疑问) about taking up cycling for health r______ (8),
talk to your doctor and ask his/her a______ (9).
In fact, you should be cycling at least two or three times a week. Don't worry if you begin to lose
your breath. Shortness of breath shows that the exercise is having the right e______ (10).
