60秒科学:Vitamins Block Some Exercise Benefits

Exercise is good for you. Antioxidants are good for you. But put them together and it’s not as good as you’d think. Because a recent study shows that some vitamins block the beneficial effects of exercise.

A good workout not only gets your heart pumping, it makes your body better able to process glucose¹ and decreases your risk of diabetes². And it does so, in part, by firing up your cells’ mitochondria. Stoking those mitochondrial flames boosts your metabolism³. But it also throws off so-called free radicals⁴, which are usually considered harmful. So adding antioxidants—which get rid of free radicals—should make your workout even healthier, right?

Well, no. Forty men took part in a four-week training program. Half the group also received daily doses of Vitamins C and E. The researchers discovered that exercise on its own improves insulin sensitivity, which keeps diabetes at bay. But taking the vitamins erased⁵ that gain—findings that appear in the May 12th issue of the Proceedings⁶ of the National Academy of Sciences.

So you actually need a burst of potentially damaging radicals to reap some of the important rewards of a good sweat. Which means that even on a molecular⁷ level: no pain, no gain.

—Karen Hopkin

1 glucose   

n.葡萄糖

参考例句：

• I gave him an extra dose of glucose to pep him up.我给他多注射了一剂葡萄糖以增强他的活力。
• The doctor injected glucose into his patient's veins.医生将葡萄糖注入病人的静脉。

2 diabetes   

n.糖尿病

参考例句：

• In case of diabetes, physicians advise against the use of sugar.对于糖尿病患者，医生告诫他们不要吃糖。
• Diabetes is caused by a fault in the insulin production of the body.糖尿病是由体內胰岛素分泌失调引起的。

3 metabolism   

n.新陈代谢

参考例句：

• After years of dieting,Carol's metabolism was completely out of whack.经过数年的节食，卡罗尔的新陈代谢完全紊乱了。
• All living matter undergoes a process of metabolism.生物都有新陈代谢。

4 radicals   

n.激进分子( radical的名词复数 )；根基；基本原理；[数学]根数

参考例句：

• Some militant leaders want to merge with white radicals. 一些好斗的领导人要和白人中的激进派联合。 来自《简明英汉词典》
• The worry is that the radicals will grow more intransigent. 现在人们担忧激进分子会变得更加不妥协。 来自辞典例句

5 erased   

v.擦掉( erase的过去式和过去分词 )；抹去；清除

参考例句：

• He erased the wrong answer and wrote in the right one. 他擦去了错误答案，写上了正确答案。 来自《简明英汉词典》
• He removed the dogmatism from politics; he erased the party line. 他根除了政治中的教条主义，消除了政党界限。 来自《简明英汉词典》

6 proceedings   

n.进程，过程，议程；诉讼(程序)；公报

参考例句：

• He was released on bail pending committal proceedings. 他交保获释正在候审。
• to initiate legal proceedings against sb 对某人提起诉讼

7 molecular   

adj.分子的；克分子的

参考例句：

• The research will provide direct insight into molecular mechanisms.这项研究将使人能够直接地了解分子的机理。
• For the pressure to become zero, molecular bombardment must cease.当压强趋近于零时，分子的碰撞就停止了。