In winter, people might lessen their outdoor exercise. The days get dark earlier, and it can be very cold! These conditions can make it harder for some of us to get outdoors for exercise.

　　冬天人们可能会减少户外运动。因为天黑得越来越早，而且天气都很冷。这种情况会让我们中的一些人更难到户外锻炼。

　　However, cold days can be perfect for outdoor workouts!

　　然而，冷天做户外锻炼可是个极佳的选择。

　　There are at least three important health benefits to cold-weather workouts.

　　寒冷天气锻炼至少有3个重要的健康益处。

　　1. The body works harder in cold weather.

　　1.寒冷天气身体会更加卖力工作

　　Health experts at the Medical University of South Carolina say the body must make extra energy to keep warm in low temperatures. This means the body is burning more calories and fat.

　　南卡罗来纳医科大学的健康专家们表示，人体在低温条件下需要制造额外能量以保持体温。这意味着身体会燃烧更多的卡路里和脂肪。

　　Your lungs also may work better in cold weather. Researchers at Northern Arizona University in Flagstaff found some interesting results in a study of goats.

　　肺在寒冷天气里也会工作更加良好。位于弗拉格斯塔夫市的北亚利桑那大学的研究人员在对山羊的研究中发现了一些有趣的结果。

　　Yes, I said "goats." But still, their results were pretty interesting.

　　没错，我说的是“山羊”。但是，他们的研究结果还是很有趣。

　　The scientists looked at how cold-weather activity affected goats. They found that "during the three coldest months, the sedentary but cold-exposed goats experienced a 34% increase in maximal oxygen uptake ... and a 29% increase in running speed." When temperatures increased in the spring both oxygen uptake and running speed of the goats decreased.

　　科学家们研究了寒冷天气的活动对山羊的影响。他们发现，“在最寒冷的三个月里，久坐不动但是暴露在寒冷中的山羊的最大摄氧量增加了34%，奔跑速度提高了29%。”当春季气温上升时，山羊的摄氧量和奔跑速度都会降低。

　　2. Regular cold-weather exercising may help the immune system.

　　2。寒冷天气定期锻炼可能对免疫系统有益

　　The winter season is also cold and flu season. Making outdoor exercise a usual part of your workout may help you avoid both colds and the flu. It may strengthen your body’s defense system.

　　冬季也是感冒和流感高发季节。让户外运动成为锻炼的一部分可以帮助人们避免感冒和流感。它可以强化人体的防御系统。

　　The Mayo Foundation for Medical Education and Research found that winter workouts can cut your risk of getting the flu by 20 to 30 percent.

　　梅奥医学教育和研究基金会发现，冬季锻炼可以把流感患病风险降低20%到30%。

　　3. Exercising outdoors in cold weather may help your mental health.

　　3.寒冷天气锻炼身体可能有益心理健康

　　Some people who suffer from "winter blues" or Seasonal Affective Disorder, may benefit from going outside to exercise in the fresh air and sunshine.

　　一些“冬季忧郁症”或是季节性情感障碍的患者可能会受益于外出在阳光和新鲜空气中锻炼身体。

　　An outdoor workout increases exposure to sunlight. Sunlight helps the body produce vitamin D. And vitamin D produces hormones that brighten your mood.

　　户外锻炼可以多晒太阳。阳光有助于身体产生维生素D，维生素D会产生让你心情愉快的激素。

　　Dangers of a cold-weather workout

　　寒冷天气锻炼的危险

　　So, there are several health benefits of exercising outdoors in very cold weather. But there are also dangers.

　　因此，看起来，寒冷天气到户外运动有多项健康益处，但它也有危险。