根据短文内容，从短文后的选项中选出能填入空白处的最佳选项。选项中有两项为余选项。
There are some injuries that are common to all types of extreme sports. The following are some of the important things to do to prevent extreme sports injuries. ____ But they can definitely minimize the risk of injuries.
Warm up.
____ They include a combination of cardiovascular(心脏血管的)exercises, strength drills and stretching. Cardiovascular exercises increase body temperature, heart rate and blood circulation, which is required for further movement of the body. Strength drills increase the stamina of the body, while stretching warms up the muscles preparing them for sudden forceful movements. ____ It also plays an important role in boosting the team spirit for a team sport. A warm-up session should last for at least 20 minutes and it can extend up to half an hour.
Avoid overworking.
There are some people who do not exercise their body for the sport on a regular basis and perform a week's task in a day or two. ____ They do not realize the effect of overworking during the performance and keep doing it until they feel extremely tired. Apart from the actual sport, one should also avoid overdoing the warm-up exercises before the activity.
____
Just as warming up is essential before any rigorous(充满活力的) physical activity, cooling down the body after playing a rigorous sport is also a significant part of physical conditioning. When you are done with your sports session, you can conclude with some walking, jogging or light running. Slight stretching exercises, focusing on specific muscles, will also be useful for cooling down the body.
A. Cool yourself down.
B. Look for a coach to train you.
C. These people are likely to suffer from extreme sport injuries.
D. However, there are no perfect methods which can assure you 100% safety.
E. Along with physical preparation, warming up prepares you mentally to begin a sport.
F. You should also be careful about your clothing selection for warmth and protection.
G. Warm-up exercises are very important before you begin any sports practice.
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