[by:www.51voa.com] [00:00.00]¸ü¶àÌýÁ¦Çë·ÃÎÊ51VOA.COM [00:00.04]From VOA Learning English, [00:02.40]this is the Health & Lifestyle report. [00:05.72]We all know that exercise keeps us healthy. [00:09.53]But two new studies get more specific. [00:13.64]They look at how exercise may lower the risk [00:16.80]of two major causes of death ¨C cancer and stroke. [00:21.32]One study says exercise may lower the risk for 13 types of cancer. [00:28.44]Another says that middle-aged people [00:31.44]can reduce their chance of having a stroke by exercising. [00:36.68]First let's talk about cancer. [00:40.40]Steven Moore of the National Cancer Institute [00:44.12]led a team of researchers to study more than 1.4 million people. [00:50.40]The study looked at participants in 12 U.S. and European groups. [00:56.20]These people reported on their physical activity between 1987 and 2004. [01:03.92]The researchers looked at the occurrence of 26 kinds of cancer [01:08.88]among the participants during, on average, the next 11 years. [01:14.88]Many participants reported walking, running and swimming. [01:19.96]The researchers took into account how long they exercised per week, [01:25.88]what they ate, if they were obese and if they smoked. [01:31.29]In an interview with NBC News, [01:34.64]Moore explains that exercise [01:37.16]"can help people reduce their risk of heart disease. [01:41.28]It can reduce the risk of diabetes." [01:44.96]It helps you live longer. [01:47.20]And now, he adds, it appears that it may reduce the risks of some cancers." [01:54.44]Moore and his team found that exercise lowered the risk of developing: [02:00.16]cancer of the esophagus by 42 percent [02:04.08]liver cancer by 27 percent [02:07.16]lung cancer by 26 percent [02:10.36]and breast cancer by 10 percent. [02:13.96]Exercise also lowered the risk of a specific type of leukemia by 20 percent. [02:20.76]Moore told NBC that there are some possible explanations for the findings. [02:27.32]First, exercise can lower hormone levels like estrogen. [02:32.72]Lower levels of estrogen would lower the risk of breast and endometrial cancers. [02:40.32]He adds that exercise helps maintain insulin [02:44.44]and that may lower overall inflammation in the body. [02:48.48]However, one type of cancer puzzled the researchers. [02:53.32]They found that exercise increased the chance of developing prostate cancer by five percent. [03:00.76]But they wrote that they could not explain the connection. [03:05.60]The researchers also found that people who did heavier exercises [03:10.76]had a slightly higher rate of skin cancer. [03:14.52]This, they say, could be from more sun exposure. [03:19.32]Now, how exercise affects strokes. [03:23.08]The more fit a person is in middle age, [03:26.32]the less likely he or she will have a crippling stroke after age 65. [03:32.68]This is the result of a new study by the University of Texas Southwestern Medical Center. [03:40.56]Doctors studied 20,000 men and women between the ages of 45 and 50. [03:47.00]They found that those who were most fit from moderate to vigorous exercise [03:53.16]had a 37 percent lower risk of a stroke than those who were least fit. [03:59.45]They say the lowered risk of a future stroke was present [04:04.20]even when the subjects had other risk factors. [04:07.92]These factors include high blood pressure and type-2 diabetes. [04:13.47]The researchers of this study say they want doctors to not ignore [04:19.52]low levels of exercise and fitness as risk factors for a stroke. [04:25.92]This study was published in the latest issue of the medical journal called Stroke. [04:31.76]I'm Anna Matteo.