Stretching and toning are certainly important， but their benefits are different from that of aerobic exercise. Surprisingly， aerobic exercise isnt just beneficial to your heart， it also sharpens your mind.

You dont have to be a jock to enjoy the brain benefits of aerobic exercise. Moderate aerobic exercise is plenty. Several studies involving older adults demonstrated that simply walking a mile or so three times a week increases blood flow in the brain and strengthens connections between neurons， resulting in improving mental performance on tasks requiring attention.

One of the studies divided a group of seniors into two different six-month exercise courses—one course consisting of aerobic exercise， the other consisting of stretching and toning. Again， were not talking about marathon-training here. The aerobic-training course gradually built its participants up to walking 45 minutes at a moderate pace three times a week.

At the end of the course， the people who completed the aerobic training showed significant improvements in attention-related mental tasks. The stretching and toning group showed little improvement.

伸展和拉伸顯然很重要，但是，對(duì)身體的益處有別于有氧運(yùn)動(dòng)。意想不到的是有氧運(yùn)動(dòng)不僅僅有益身心，還能靈活大腦。

享受有氧運(yùn)動(dòng)對(duì)于大腦健康的福利，并不一定要向運(yùn)動(dòng)員般劇烈運(yùn)動(dòng)。適度有氧運(yùn)動(dòng)就獲益頗多了。一些有關(guān)老年人的研究證實(shí)，只需每周三次散步一英里左右就能促進(jìn)大腦血液循環(huán)；增強(qiáng)神經(jīng)元間的“互動(dòng)”，提高注意力，從而提升智力。

一項(xiàng)研究將老人們分為兩組：一組做有氧運(yùn)動(dòng)；另一組做伸展和無氧拉伸半年的時(shí)間。但是，運(yùn)動(dòng)量都是適度的而非馬拉松式。有氧運(yùn)動(dòng)組讓老人們養(yǎng)成了每周三次45分鐘正常步伐走路。

有氧運(yùn)動(dòng)訓(xùn)練完后，參加者在注意力相關(guān)的智能測試有顯著提升。而后一組受訓(xùn)前后并無明顯差異。