來源:http://tw.news.yahoo.com/article/url/d/a/080201/17/swhe.html

運動可減緩老化！　英研究：效果DNA上看得到

運動能夠降低罹患各種疾病的機率，是大家都知道的常識，不過英國最新的研究發現，運動還能夠減緩老化，而且效果全部都可以在每一個細胞的DNA上看到，到底怎麼回事？

運動好處非常多，不但能夠讓身體健康，還可以讓老化的速度變慢，英國科學家甚至發現，運動的好處可以直接在DNA上看到。研究教授艾波斯：「細胞反映身體的老化，細胞老化和罹患疾病以及壽命，有絕對的關係。」

灰色條狀物是由DNA組成的染色體，白色點狀物叫做「端粒體」，「端粒體」越長，細胞就越年輕，科學家對2400個雙胞胎進行抽血調查，結果發現，每天有運動30分鐘的受訪者，端粒體明顯比沒有運動的還要長，有些細胞甚至年輕了10歲。

研究教授艾波斯：「這是第一個直接顯示老化的研究，非常令人興奮。」

這是第一次老化現象可以具體地量化，並且用顯微鏡觀察，科學家推測，運動可以減少發炎和壓力，這兩個因素都會減短細胞的壽命，專家表示，運動好處多多，沒有時間運動，絕對不是藉口。

英文原文:
http://www.sciam.com/article.cfm?id=new-study-links-exercise-to-longevity

News - January 28, 2008

Work It Out: More Activity = Slower Aging
New study links exercise to greater longevity
By Lisa Stein



AGING FAST: A new study shows that lack of exercise may speed the aging process.
iStockPhoto
Warning, couch potatoes: resting on your laurels may be hazardous to your health, not to mention make you old before your time.

\"A sedentary lifestyle increases the propensity to aging-related disease and premature death,\" researchers at King\'s College London report today in the journal Archives of Internal Medicine. \"Inactivity may diminish life expectancy not only by predisposing to aging-related diseases but also because it may influence the aging process itself.\"

Researcher Lynn Cherkas and colleagues reached their conclusions by examining the genetic material extracted from blood samples of some 2,400 twins. They specifically studied the length of telomeres (repeated DNA sequences) on the ends of chromosomes in leukocytes (white blood cells); the protective caps are believed to be markers of biological aging, because they shrink over time.

Their findings: the telomeres of subjects who exercised the most (an average of 199 minutes weekly) were longer than those of volunteers who worked out the least (a mere 16 minutes or less a week). The discrepancy was enough, researchers wrote, to suggest that the exercise mavens were on average as much as a decade biologically younger than the slackers.

\"Such a relationship between leukocyte telomere length and physical activity level remained significant after adjustment for body mass index, smoking, socioeconomic status and physical activity at work,\" the authors report. \"The mean difference in leukocyte telomere length between the most active and least active subjects was 200 nucleotides (chemical structural units of DNA and RNA), which means that the most active subjects had telomeres the same length as sedentary individuals up to 10 years younger, on average.\"

The scientists speculate that stress, inflammation and oxidative stress (cell damage caused by oxygen exposure) may be responsible for shortened telomeres in physically inactive people. Exercise is among the factors found to help alleviate stress. Previous research has linked regular workouts to lower rates of cardiovascular disease, type 2 diabetes, cancer, high blood pressure, obesity and osteoporosis.

The researchers note that their findings support U.S. guidelines calling for individuals to exercise moderately for 30 minutes at least five days a week. \"Our results. . . show that adults who partake in regular physical activity are biologically younger than sedentary individuals,\" they say. \"This conclusion provides a powerful message that could be used by clinicians to promote the potential anti-aging effect of regular exercise.\"





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