Unit 112：Get out into the cold第112单元：迎向寒冷People don't need to hibernate all winter long,although you wouldn't know it from the increase in couch potatoes when the first frost shows up.人类是不需要冬眠的，不过寒冬初至，窝在沙发上看电视的人便多起来，这点使我们忘了我们是不需要冬眠的。You may be cozy,but you'll never lose any weight that way.你也许觉得温暖又舒适，但那样却不能使你减轻任何体重。Bundle up and stay active.Getting involved in a winter sport follows the same basic principle.穿着暖和保持活力。参与冬季运动须遵照同样的基本原则。In winter,your body burns more calories to keep you warm.冬天时，你的身体会燃烧更多的卡路里来保暖。Cross-country skiing,for instance,burns somewhere between 500 and 700 calories an hour.举例来说，越野滑雪每小时就可燃烧大约五百至七百卡路里的热量。