Once when I was facing a decision that involved high risk, I went to a friend. He looked at me for a moment, and then wrote a sentence containing the best advice I've ever had: Be bold and brave — and mighty (强大的) forces will come to your aid.

      Those words made me see clearly that when I had fallen short in the past, it was seldom because I had tried and failed. It was usually because I had let fear of failure stop me from trying at all. On the other hand, whenever I had plunged into deep water, forced by courage or circumstance, I had always been able to swim until I got my feet on the ground again.

          Boldness means a decision to bite off more than you can eat. And there is nothing mysterious about the mighty forces. They are potential powers we possess: energy, skill, sound judgment, creative ideas — even physical strength greater than most of us realize.

       Admittedly, those mighty forces are spiritual ones. But they are more important than physical ones. A college classmate of mine, Tim, was an excellent football player, even though he weighed much less than the average player. “In one game I suddenly found myself confronting a huge player, who had nothing but me between him and our goal line,” said Tim. “I was so frightened that I closed my eyes and desperately threw myself at that guy like a bullet（子弹） — and stopped him cold.”

       Boldness — a willingness to extend yourself to the extreme—is not one that can be acquired overnight. But it can be taught to children and developed in adults. Confidence builds up. Surely, there will be setbacks (挫折) and disappointments in life; boldness in itself is no guarantee of success. But the person who tries to do something and fails is a lot better off than the person who tries to do nothing and succeeds.

       So, always try to live a little bit beyond your abilities—and you'll find your abilities are greater than you ever dreamed.

    Retired nurse Sue Collins was just beginning the second length of her local pool when her morning swim suddenly became anything but a pleasure.

    Two months ago Sue, 69, who has never suffered from asthma or any other breathing problem in the past, suddenly found herself hard for breath.

    “I felt as if my throat and oesophagus (食道) were closing up,” says Sue.

    Sue is convinced the problem is related to the indoor swimming baths. “I spend half the year in Turkey and swim every day outside in a pool or the sea there and never have this problem,” she says.

    She may be right, because although a trip to the pool is the perfect exercise for many, the chlorine (氯气) used to keep the water free from germs can lead to problems.

    But in most cases it's not the chlorine that causes problems, but the by-products formed when chlorine interacts with other substances — and this is mostly due to people not showering before they enter the pool.

    “This then poisons the water for them and for others,” says Dr. Hull. “The chlorine interacts with sweat and urine(尿素) on the skin and forms by-products called chloramines that float above the surface as a gaseous solution that can be inhaled in.”

    Chloramines are heavier than air so hang over the water where they are easily breathed in. Some believe they may cause lung disorders. A Swedish study in 2013 examining the health of 146 workers at 46 indoor pools found that 17 per cent had airway trouble at work — but no problems at home.

    As Dr. Hull says: ‘People need to remember that showering isn't just for them. It is for the greater good.'

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    Why do Americans struggle with watching their weight, while the French, who consume rich food, continue to stay thin? Now a research by Cornell University suggests how life style and decisions about eating may affect weight. Researchers concluded that the French tend to stop eating when they feel full. However, Americans tend to stop when their plate is empty or their favorite TV show is over.

    According to Dr. Joseph Mercola, a health expert, the French see eating as an important part of their life style. They enjoy food and therefore spend a fairly long time at the table, while Americans see eating as something to be squeezed between the other daily activities. Mercola believes Americans lose the ability to sense when they are actually full. So they keep eating long after the French would have stopped. In addition, he points out that Americans drive to huge supermarkets to buy canned and frozen foods for the week. The French, instead, tend to shop daily, walking to small shops and farmers' markets where they have a choice of fresh fruits, vegetables, and eggs as well as high-quality meats for each meal.

    After a visit to the United States, Mireille Guiliano, author of French Women Don't Get Fat, decided to write about the importance of knowing when to stop rather than suggesting how to avoid food. Today she continues to stay slim and rarely goes to the gym.

    In spite of all these differences, evidence shows that recent life style changes may be affecting French eating habits. Today the rate of obesity — or extreme overweight — among adults is only 6%. However, as American fast food gains acceptance and the young reject older traditions, the obesity rate among French children has reached 17% — and is growing.

    We may think we're a culture that gets rid of our worn technology at the first sight of something shiny and new, but a new study shows that we keep using our old devices（装置）well after they go out of style. That's bad news for the environment – and our wallets – as these outdated devices consume much more energy than the news ones that do the same things.

    To figure out how much power these devices are using, Callie Babbitt and her colleagues at the Rochester Institute of Technology in New York tracked the environmental costs for each product throughout its life – from when its minerals are mined to when we stop using the device. This method provided a readout for how home energy use has evolved since the early 1990s. Devices were grouped by generation. Desktop computers, basic mobile phones, and box-set TVs defined 1992. Digital cameras arrived on the scene in 1997. And MP3 players, smart phones, and LCD TVs entered homes in 2002, before tablets and e-readers showed up in 2007.

    As we accumulated more devices, however, we didn't throw out our old ones. "The living-room television is replaced and gets planted in the kids' room, and suddenly one day, you have a TV in every room of the house," said one researcher. The average number of electronic devices rose from four per household in 1992 to 13 in 2007. We're not just keeping these old devices – we continue to use them. According to the analysis of Babbitt's team, old desktop monitors and box TVs with cathode ray tubes are the worst devices with their energy consumption and contribution to greenhouse gas emissions（排放）more than doubling during the 1992 to 2007 window.

    So what's the solution? The team's date only went up to 2007, but the researchers also explored what would happen if consumers replaced old products with new electronics that serve more than one function, such as a tablet for word processing and TV viewing. They found that more on-demand environment viewing on tablets instead of TVs and desktop computers could cut energy consumption by 44%.

    Should you work out in the gym in the morning instead of in the evening? It all depends. Of course, there are advantages of working out(运动) in the morning.

    You will increase your energy for the rest of the day. “Morning workouts result in better energy levels throughout the day and give you more mental sharpness,” says Dr. Cedrie Byrant, Chief Science Officer of the American Council on Exercise.

    Here is another advantage. In 2017, health researchers found that exercising in the morning helps you sleep better at night. According to the study, in all cases, those who exercised at 7:00am experienced about a 10 percent drop in blood pressure that carried through the rest of the day. They also had about a 25 percent drop in blood pressure at night, slept longer and had more beneficial sleep cycles than when they exercised at other times of the day.

    However, there are disadvantages, too.

    If you are not an early riser, getting out of the bed in the morning can be very difficult. Byran says that if you're not used to exercising in the morning and force yourself to get up, you may not put as much effort into the exercise as you would later in the day. Also, if you aren't careful, you can damage your sleep schedule, which can lead to insufficient sleep.

    Besides, hitting the gym before work can cause a challenge in terms of scheduling. If you work a 9-to-5 job, getting ready for work and going to work can cut your morning workout short, Byrant notes.

    To sum up, it has both advantages and disadvantages. If it suits you better to work out in the morning, you can do so.

    Turning the lights out or wearing a blindfold while eating could be a quick way to lose weight, according to scientists. The simple trick works because it stops diners eating for pleasure rather than for calories. It also triggers (引发) a part of the brain that is worried that unseen food may go bad.

    An experiment by the University of Konstanz, in Germany, found that people who were blindfolded consumed nine percent fewer calories before they felt full, compared to those who could see. They also vastly overestimated how much they had eaten because they could not see how much was left on the plate. Blindfolded volunteers estimated(估计) they had eaten 88 percent more than they actually had.

    Scientists believe that not seeing food on the table also allows the body to know when it is full in real time rather than remembering past experiences where it might have taken a full plate to feel full.

    In the experiment, 50 people were blindfolded and 40 were allowed to see their food. All were told not to eat within two hours of the experiment. They were then given three 95g bowls of chocolate ice cream and invited to eat for 15 minutes. Their bowls were taken away and the remaining ice-cream weighed, while the participants were quizzed on how much they thought they had eaten.

    On average the group who could see ate 116g while the blindfolded groups ate 105g. However, the blindfolded group believed they had eaten 197g while compared with 159g for the non-blind volunteers. They were also asked how pleasant the ice-cream tasted and the blindfolded group rated lower than those who could see.

    “The experienced pleasure of eating was significantly lower in the blindfolded group. Not seeing the food might have decreased the appetite. Sight plays an important role in the eating experience and in the overall dining experience.”

    Previous studies have shown that the visual influence of food plays a large part in the taste. While restaurants that allow diners to eat in the dark state that it triggers other senses, in fact eating in darkness is likely to taste far milder than usual.