【今日阅读推荐】本篇阅读材料“科学家称快步走比跑步健康”选自《卫报》（原文标题：Brisk walk healthier than running – scientists 2013.4.5）。

　　Both produce benefits but walking cuts risk of heart trouble by a greater amount when the same energy is expended.
　　Brisk walking reduces the risk of heart disease more effectively than running when the energy expenditure of both activities is balanced out, a study has found.
　　Researchers compared data from two studies of 33,060 runners and 15,045 walkers. For the same amount of energy used, walkers experienced greater health benefits than runners.
　　The effects on participants, who were aged 18 to 80, were observed over a period of six years.
　　Running reduced the risk of heart disease by 4.5% while walking reduced it by 9.3%.
　　Calorie for calorie, walking also had a stronger impact on heart disease risk factors. The risk of first-time high blood pressure was reduced by 4.2% by running and 7.2% by walking.
　　First-time high cholesterol risk was lowered by 4.3% by running and 7% by walking.
　　The risk of first-time diabetes was reduced by about 12% by both walking and running.
　　"Walking and running provide an ideal test of the health benefits of moderate-intensity walking and vigorous-intensity running because they involve the same muscle groups and the same activities performed at different intensities," said study leader Dr Paul Williams, from the Lawrence Berkeley National Laboratory in California.
　　"The more the runners ran, and the walkers walked, the better off they were in health benefits. If the amount of energy expended was the same between the two groups, then the health benefits were comparable.
　　"People are always looking for an excuse not to exercise but now they have a straightforward choice to run or to walk and invest in their future health."
　　The research is reported in the American Heart Association journal Arteriosclerosis, Thrombosis and Vascular Biology.

　　【重点单词及短语】
　　Brisk walking 快步走
　　balance out 抵消；平衡
　　moderate-intensity 中等强度的
　　vigorous-intensity 高强度的

　　Question time:
　　1. What's the study result in the passage?
　　2. When the same amount of energy is consumed, who benefit more? runners or walkers?