As we age, even if we’re healthy, the heart just isn’t as efficient in processing oxygen as it used to be. In most people the first signs show up in their 50s or early 60s. And among people who don’t exercise, the changes can start even sooner.
随着年龄的增长，即使我们健康，心脏处理氧气的效率也不如以前那样。大多数人在50多岁或60多岁时会出现最初的迹象。而在不锻炼的人群中，这种变化甚至可能更早出现。

“Think of a rubber band. In the beginning, it is flexible, but put it in a drawer for 20 years and it will become dry and easily broken,” says Dr. Ben Levine, a heart specialist at the University of Texas. That’s what happens to the heart. Fortunately for those in midlife, Levine is finding that even if you haven’t been an enthusiastic exerciser, getting in shape now may help improve your aging heart.
“想象一根橡皮筋。一开始它很柔韧，但放在抽屉里20年后就会变干，很容易断裂，”得克萨斯大学的心脏专家本·莱文士说。心脏就是这样的情况。对于那些中年人来说，幸运的是，即使你以前不是一个热衷于锻炼的人，现在开始保持健康可能有助于改善你老化的心脏。

Levine and his research team selected volunteers aged between 45 and 64 who did not exercise much but were otherwise healthy. Participants were randomly divided into two groups. The first group participated in a program of nonaerobic (无氧) exercise—balance training and weight training—three times a week. The second group did high-intensity aerobic exercise under the guidance of a trainer for four or more days a week. After two years, the second group saw remarkable improvements in heart health.
莱文和他的研究团队选择了45至64岁之间运动不多但其他方面健康的志愿者。Participants were randomly divided into two groups. 第一组每周参加三次非有氧运动——平衡训练和重量训练。第二组在教练的指导下进行高强度的有氧运动，每周进行四天或更多次。两年后，第二组在心脏健康方面看到了显著的改善。

“We took these 50-year-old hearts and turned the clock back to 30-or 35-year-old hearts,” says Levine. “And the reason they got so much stronger and fitter was that their hearts could now fill a lot better and pump (泵送) a lot more blood during exercise.” But the hearts of those who participated in less intense exercise didn’t change, he says.
“我们让这些50岁的心脏重新回到30或35岁的状态，” Levine说。“他们的心脏变得更强壮、更健康的原因是，他们的心脏现在能够在运动时更充分地充血并泵送更多的血液。” 但是，他说，那些参加较轻松运动的人的心脏没有变化。

“The sweet spot in life to start exercising, if you haven’t already, is in late middle age when the heart still has flexibility,” Levine says. “We put healthy 70-year-olds through a yearlong exercise training program, and nothing happened to them at all.”
“如果你还没有开始运动，那么晚中年是生命中最适合开始运动的时机，此时心脏仍然具有灵活性，” Levine说。“我们让健康的70岁老人参加为期一年的运动训练项目，他们的情况没有任何改变。”

Dr. Nieca Goldberg, a spokeswoman for the American Heart Association, says Levine’s findings are a great start. But the study was small and needs to be repeated with far larger groups of people to determine exactly which aspects of an exercise routine make the biggest difference.
美国心脏协会发言人尼卡·戈德堡博士表示，莱文的研究成果是一个很好的开端。但是这项研究规模较小，需要用更大的人群重复进行，以确定运动计划的哪些方面起到最大的作用。

1. What does Levine want to explain by mentioning the rubber band?
   A The right way of exercising.
   B The causes of a heart attack.
   C The difficulty of keeping fit.
   D The aging process of the heart.
   答案：D

2. In which aspect were the two groups different in terms of research design?
   A Diet plan.
   B Professional background.
   C Exercise type.
   D Previous physical condition.
   答案：C

3. What does Levine’s research find?
   A Middle-aged hearts get younger with aerobic exercise.
   B High-intensity exercise is more suitable for the young.
   C It is never too late for people to start taking exercise.
   D The more exercise we do, the stronger our hearts get.
   答案：A

4. What does Dr. Nieca Goldberg suggest?
   A Making use of the findings.
   B Interviewing the study participants.
   C Conducting further research.
   D Clarifying the purpose of the study.
   答案：C