For more than one hundred years, a great number of scientists have believed that tiredness in athletes originates in the muscles(肌肉). Precise explanations have varied, but all have been based on the “Limitations Theory”. In other words, muscles tire because they hit a physical limit—they either run out of fuel or oxygen or they drown in harmful by-products(副产品).
In the past few years, however, Timothy Noakes from the University of Cape Town, South Africa, has examined this standard theory. Tiredness, he argues, is caused not by signals springing from overtaxed muscles, but is an emotional response which begins in the brain. The fundamental nature of his new theory is that the brain paces the muscles to keep them well back from the edge of tiredness. When the brain decides it’s time to quit, it creates unbearable muscle tiredness. This “Central Governor” theory remains controversial, but it does explain many puzzling aspects of athletic performance.
A recent discovery that Noakes calls the “lactic acid paradox” made him start researching this area seriously. Lactic acid is a by-product of exercise, and the increase of it is often mentioned as a cause of tiredness. But when research subjects exercise in certain conditions created artificially, they become tired even though lactic acid levels remain low. Nor has the oxygen content of their blood fallen too low for them to keep going. Obviously, something else was making them tire before they hit either of these physiological limits.
Noakes conducted an experiment with seven cyclists. It has long been known that during exercise, the body never uses 100% of the available muscle fibres(纤维). The amount used varies, but in some tasks such as this cycling test the body calls on about 30%. His team found that as tiredness set in, the electrical activity in cyclist’s legs declined—even when they were making a great effort to cycle as fast as they could.
To Noakes, this was strong evidence that the old theory was wrong. “The cyclists may have felt completely exhausted,” he says, “but their bodies actually had considerable reserves that they could theoretically tap by using a greater amount of the resting fibres.” This, he believes, is the proof that the brain is regulating the pace of the workout to hold the cyclists well back from the point of extreme tiredness.
1. Why do athletes feel tired according to “Limitations Theory”?| A．Because the muscles run out all energy. |
| B．Because the brain protects the muscles. |
| C．Because the scientists performed researches. |
| D．Because Noakes examined standard theory. |
| A．Muscle fibres control athletes’ movements. |
| B．Lactic acid levels remain high in cycling tests. |
| C．Mental processes control the symptoms of tiredness |
| D．Different exercises use different amount of muscle fibres |
| A．The energy in human bodies can be balanced |
| B．Tiredness is a harmful by-product of exercise. |
| C．Lactic acid will not caused tiredness necessarily. |
| D．The oxygen content will rise after taking exercise. |
| A．Muscles or Brains?——Which brings athletes tiredness? |
| B．Lactic acid or Oxygen content——Which is vital for athletes? |
| C．Working out or Being relaxed——Which will better our health? |
| D．Common belief or New discovery——Which should we believe? |
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【推荐1】If your partner gets down on one knee to propose, or you get a call with the job offer, your reaction might be to shout it from the rooftops. But new research suggests that keeping good news a secret before telling someone else could make people feel more energized.
“Decades of research on secrecy suggest it is bad for our well-being. However, this work has only examined keeping secrets that have negative effects for our lives. Is secrecy inherently bad for our well-being or do the negative effects of secrecy tend to originate from keeping negative secrets?” asked lead researcher of the latest research Michael Slepian, PhD, a professor of business at Columbia University.
In the experiment, some participants were asked to reflect on the good news they kept secret, while others reflected on good news that was not secret, and then rated how energized the news made them feel and whether they intended to share the news with someone else. The researchers found that the participants who reflected on their positive secrets reported feeling more energized than the participants who thought about their good news that was not secret.
The research nuances our understanding of the science of secrets. Negative secrets tend to deplete us and have also been linked to anxiety and depression. Positive secrets, however, seem to have an energizing effect and make people alive. One factor could be that people often have different motivations for keeping good news to themselves. Those with positive secrets were much more likely to keep quiet for internal reasons, not because they felt any outside pressures.
“People sometimes go to great lengths to plan revealing a positive secret to make it all the more exciting. This kind of surprise can be intensely enjoyable, but surprise is the most fleeting of our emotions, ” Slepian said. “Having extra time days, weeks or even longer-to imagine the joyful surprise on another person’s face allows us more time with this exciting moment, even if only in our own minds.”
1. What did Michael Slepian think of the previous research on secrecy?| A．One-sided. | B．Pointless. | C．Convincing. | D．Pioneering. |
| A．they were optimistic and cheerful. |
| B．they were free from secrets. |
| C．they had undisclosed positive secrets. |
| D．they had shared good news with others. |
| A．Spoil. | B．Exhaust. | C．Confuse. | D．Panic. |
| A．Never reveal a secret casually. |
| B．Let your imagination run wild. |
| C．Be creative when surprising others. |
| D．Delay sharing a positive secret. |
【推荐2】“Doppelgänger” is a German word which means “double-goer”, a person who looks exactly like you but has no relationship with you. Luckily, the math says that it’s just about impossible and that you are unique.
If we are talking about measurements of the face, there is a small chance that 2 or more people will match one another on 8 measurements of the face, which include ear length and the space between the centers of the right and left eyes. However, if we look at measurements of the body, the chance is even lower. This is because these measurements are larger. Two people may look very similar at first sight, but when you start the measurement they will not match each other.
Many of us have had the experience of being greeted by a stranger and asked if we were someone we weren’t. It’s easy for us to believe in the possibility of doppelgängers. It’s more possible that you’ll see a doppelgänger of an acquaintance than your mom. You know your mom really well and you can find the difference quickly, but for an acquaintance, it’s not the case.
The result that doppelgängers aren’t really a thing doesn’t mean that researchers will stop their research into body features any time soon. In fact, the differences in human features are becoming more important and measurements of the body are more unique than those of the face. Many wrongdoers who are caught on camera cover their faces, so we need to find out if we can use the body in the same way as the face is used.
1. What can be learnt from Paragraph 2?| A．Measurements of the face are not exact. |
| B．There are no similar people in the world. |
| C．People are more similar in body measurements. |
| D．People are less alike in body measurements. |
| A．They don’t believe in face measurements. |
| B．There are many twins around the world. |
| C．They don’t know the “doppelgängers” so well. |
| D．There were doppelgängers in German history. |
| A．They are helpful. | B．They are popular. |
| C．They are against the law. | D．They are difficult to make. |
| A．You can be measured mathematically | B．You are the only one in the world |
| C．Who can be your doppelgänger? | D．Why are there doppelgängers? |
【推荐3】It's common to communicate by way of text, and that works well for everything from setting plans with a friend to asking you to pick up a grocery item.
● There's no vocal tone involved
When we speak, the person we're talking to can tell how serious or light we are by our tone.
●
We also communicate in person through nonverbal ways. How we act physically lets others know how we feel. And without that in text, an argument can be worsened to a terrible point without one person even becoming aware of how upset the other is.
● Different communication paces affect a lot
● Emojis and gifs can be hurtful
In the same way that visual communication tools like emojis and gifs can add fun to conversations, they can also make things much worse in a text disagreement. It can be challenging to know when you've taken emojis or gifs to a hurtful place, especially if the other person holds in that information and doesn't tell you at the moment.
| A．Body language is absent |
| B．Text, on the other hand, has no tone |
| C．Long-term healthy relationships collapse |
| D．Texting is generally a quick back-and-forth exchange |
| E．This happens if he is feeling unsafe in the discussion |
| F．However, we may have taken communication by text too far |
| G．Our tone tells us a conversation is heading in the wrong direction |
【推荐1】Two “stolen” notebooks written by Charles Darwin were returned to Cambridge University, nearly 22 years after they went missing. The notebooks included the scientist’s famous Tree of Life sketch(草图) and were believed to have been taken in November 2000. Both notebooks were returned to the library in their original file boxes, and included a printed message which read, “Librarian — Happy Easter... X”.
Speaking to the BBC, Cambridge University’s librarian Dr Jessica Gardner said she felt “joyous” at their return. Initially, librarians had thought the notebooks had been misplaced by staff. After various checks through the years, head librarian Dr Gardner eventually reported the notebooks as stolen to the police in 2020.
Dr Gardner was also worried that the notebooks might have taken a lifetime or longer to come back. “I thought it might take years. My sense of relief at the notebooks’ safe return is profound and almost impossible to adequately express. I was heartbroken to learn of their loss and my joy at their return is immense.”
“There have been tears,” she added. “And I think there still will be, because we are not over the emotional roller coaster. It means so much to us to have these home.”
According to Dr Gardner, Cambridge University Libraries will be pulling the notebooks on display this summer, as part of the upcoming exhibition Darwin In Conversation, which opens oil July 9.
1. Who “stole” the notebooks?| A．A library staff member. | B．A scientist researching Darwin. |
| C．Dr Jessica Gardner. | D．Someone we don’t know. |
| A．the police found the “thief” from the message |
| B．the notebooks were damaged to some degree |
| C．the notebooks are very valuable documents |
| D．the notebooks were “stolen” during the Easter |
| A．It’s thrilling and risky. | B．It’s hard but worthwhile. |
| C．It’s unexpected while joyful. | D．It’s sceptical and unbelievable. |
| A．Notebooks that Reflects Charles Darwin’s Genius |
| B．Darwin’s Notebooks Found in Cambridge University |
| C．Charles Darwin’ Notebooks Returned after 22 Years |
| D．Darwin In Conversation, an Exhibition You Can’t Miss |
【推荐2】The Last Generation is an activist group in Germany, the name implying that our unsustainability will push us to extinction. To force their government into action, some of the group went on a month-long hunger strike in August 2021. It wasn’t a half-hearted effort: several ended up in hospital.
But I’d like to take the opposite framing. I think we have the opportunity to be the first generation that leaves the environment in a better state.
There are two kinds of optimism: complacent optimism and conditional optimism. Complacent optimism is the feeling of a child waiting for presents. Conditional optimism is the feeling of a child who is thinking about building a tree house, “If I get some wood and nails and persuade some other kids to help do the work, we can end up with something really cool.” The group actually did take bold action, yet I want to address the climate crisis from a different angle.
Yes, my framing seems hard to believe. I’ll explain why. Here I’m using the term “generation” loosely. I am from a generation that will be defined by our environmental problems. I was a child when climate change really began. I will see countries move from being almost entirely dependent on fossil fuels to being free of them. I will be 57 when governments hit the “2050 deadline” of reaching net-zero carbon emissions that so many have promised.
But, of course, there will be several generations involved in this project. There are a couple above me and a couple below me. And we all need to work together to achieve that.
For a conditional optimist, criticism is essential. We need to work through ideas to find the most promising ones. Most innovators have been optimists. But they were also strongly critical: no one would pick apart the ideas of Thomas Edison or Marie Curie more than they did themselves.
Don’t look away from the climate crisis that faces us. Let’s face up to it, not from a place of “damage control” but with a clear vision of the future we can build: one that not only stops warming in its tracks but builds a better world for us, all of us, and the species hat we share the planet with.
1. Why is The Last Generation introduced?| A．To blame them for their action. | B．To remind Germany of its duties. |
| C．To discuss the author’s perspective. | D．To demand urgent action from everyone. |
| A．Belief in kindness. | B．Passive expectation. |
| C．Brief satisfaction. | D．Love of presents. |
| A．Turn to. | B．Identify with. | C．Find fault with. | D．Make an assessment of. |
| A．Envision and engage. | B．Adapt and advance. |
| C．Inspire and innovate. | D．Explore and expand. |
【推荐3】Movies and TV shows see dolphins as helpful, playful creatures. “The world loves a good dolphin story,” Blake Morton, a scientist who studies animal behavior, told TIME. “And I think one reason for that is we see a lot of ourselves reflected in their behavior.”
Morton used scientific methods to test this. The result of this work is a new report showing that humans and dolphins share certain personality traits (个性特点).
The study included 134 bottlenose dolphins in eight countries. Each dolphin was observed and rated by several people, using a “dolphin personality questionnaire (调查表).” The questionnaire had more than 40 items. It included adjectives such as “playful” and “intelligent”. Scientists gave every dolphin a score from 1 to 5 for each item, based on how well it described the animal’s behavior.
From these ratings, Morton and his team were able to find personality traits that are common in dolphins. The results show that dolphins and humans have some similar personality traits. Most obviously, the two species (物种) share traits related to curiosity and sociability.
Morton’s dolphin study and others like it help us learn about other species. But they also help us learn about ourselves. “My kind of work comes from the spirit of trying to understand what made humans the way we are,” Morton says. “One way we can do that is to compare our behavior to other species.”
Scientists around the world are researching different animal species. Their research raises important questions that future scientists will work to answer. “It’s all a big puzzle (迷宫),” Morton says. “It takes thousands of careful papers being printed before you start to see the puzzle coming together.” He compares scientific research to pointillism. That’s a painting style in which an artist makes a picture using lots of tiny dots (点). “If you take a step back and look at all those little single points of work,” Morton says, “you’ll see a big picture come into view.”
1. What did Morton’s dolphin study find?| A．Dolphins are more popular in TV shows than other animals. |
| B．Dolphins have personality traits very similar to humans. |
| C．Dolphins are helpful and playful creatures. |
| D．Dolphins are more curious than humans. |
| A．The importance of studying dolphin behavior. |
| B．Why Morton’s team created the questionnaire. |
| C．How Morton’s team carried out the study. |
| D．The methods of observing dolphins. |
| A．Finding the similarities between dolphins and humans. |
| B．Having a deeper understanding of humans. |
| C．Protecting dolphins more scientifically. |
| D．Learning about other animals. |
| A．Progress in science is made little by little. |
| B．Scientific research should be taken seriously. |
| C．Art plays an important role in scientific research. |
| D．Scientists around the world should work together. |
