【推荐2】Training for a marathon can be a marathon itself. Here are tips on preparing for the big day. Learn how to be prepared for the race and how to treat your body after that long run. 

Your last long run should take place about three weeks prior to the marathon. It takes that long for the muscle damage caused by training to go. Adding one more long run could have minimal gain, if any, and may cause an athlete to suffer from “dead legs” during the event.

Like you reduce your work to restore your muscles, focus on sleep the week prior to the race. Your body will appreciate it. Even if nervousness stops you from getting sleep the night before the race, the extra sleep you got during this week will make up for this.

Be sure you have on hand your water and food sources for the race. Drink lots of water during the week before the race. This optimizes your hydration (补水) before you hit the start line. Eat a diet rich in complex carbohydrates, such as breads, rice, pasta and potatoes. This helps maximize your energy stores. Don’t experiment with new foods this week. Carbohydrate loading (碳水循环) is not a simple process. Try it some other time, perhaps before other long runs. 

No matter what the results are, be proud of yourself. You can learn from every race. Some tips for your post-marathon:

Drink. Even though you drank during the race, you will still be a little dehydrated.

Keep moving. Do lower intensity exercises, such as walking for 60 minutes after the race. This will ease a lot of the post-race muscle pain. Stretch gently. But don’t plan on running during the week after the race. Walking, swimming or cycling at an easy pace will work well.

Do allow your body to recover. An extreme athletic event like a marathon is incredibly stressful on the body. The body needs the rest; otherwise, problems such as injuries, fatigue, decreases in performance and immune suppression can result.

【推荐2】Electronics woven (编织) into fabrics promise to open up all kinds of interesting possibilities, from clothing that monitors muscle activity and tracks breathing, to garments that can talk to one another. Developing pliable power sources to go with them is an equally important field of research, so scientists at the University of British Columbia have put forward a particularly impressive solution that they say could be the first ever battery that is both stretchable and washable.

To develop a battery with such capabilities, the scientists reimagined the way these devices are put together. Rather than forming a lithium-ion battery packed with hardened materials inside a rigid exterior, the team turned to an alternative chemistry in zinc-manganese (锌锰) dioxide, which is appealing for its low cost and safety. These materials were ground down into tiny pieces and inset in a polymer (聚合物) to form very thin and stretchable layers.

“We went with zinc-manganese because for devices worn next to the skin, it’s a safer chemistry than lithium-ion batteries, which can produce deadly compounds when they break,” says Nguyen.

The resulting battery is flexible and can be stretched to twice its normal length, has a specific capacity of 160 mAh g-1 and keeps 75 percent of its capacity over 500 charge and discharge cycles. Impressively, the team found the battery to withstand 39 wash cycles so far.

The team is now working to improve the power output and lifetime of the battery, and says the creation has already attracted commercial interest, with the cost expected to be similar to a standard rechargeable battery. They imagine it being put to use in watches and patches that measure vital signs, and in smart clothing that does much the same thing.

【推荐3】In a study published in The Journal of the Acoustical Society of America, Diana Deutsch of the University of California and her co-authors find that musicians who speak an East Asian tone language fluently are much more likely to have perfect pitch(音高).

Unlike English, many East Asian languages, such as Mandarin, Cantonese and Vietnamese, are “tonal”, so that a word’s meaning often depends on the tone in which it is said. So learning perfect pitch is, for fluent speakers of a tone language, similar to learning a second tone language.

The study looked at 203 students at the University of Southern California’s Thornton School of Music through a test. The students listened to the 36 notes. They attempted to identify the notes, and they self-reported their musical, ethnic and linguistic backgrounds — including whether they were very fluent in an East Asian tone language, fairly fluent or not at all fluent. Deutsch and her colleagues found that students who spoke an East Asian tone language very fluently scored nearly 100 percent on the test, and that students who were only fairly fluent in a tone language scored lower overall. Those students who were not at all fluent in speaking a tone language scored the worst on average.

Deutsch acknowledges that it still remains to be discovered why and how it is that some speakers of non-tone languages have perfect pitch. She expects it to be related to either an exceptionally long “critical window” for language acquisition, a very early musical upbringing, or both.

“Perfect pitch for years seemed like a beautiful gift — given only to a few genetically talented people. But our research suggests that it might be available to virtually everybody,” Deutsch said. She also proposed that parents who want their kids to acquire perfect pitch should expose them to musical tones from infancy onwards.