4 .                                                                                      You May Need a Few Minutes of Brisk Activity

Walking from room to room, running up and down stairs to deliver folded laundry, or taking a jog around the block... Which ones would best help or hurt your brain? A recent study attempted to a answer that question by strapping( 绑上) activity monitors to the thighs of nearly 4,500 people in the United Kingdom and ________ their 24-hour movements for seven days. Researchers then examined how participants’ behavior affected their short-term memory, problem-solving and processing skills.

Here’s the good news. People who spent “even small amounts of time in more vigorous activities—as little as six to nine minutes—compared to sitting, sleeping or gentle activities had ________ cognition scores,” said study author John Mitchell.

Moderate physical activity is ________ defined as brisk walking or bicycling or running up and down stairs. Vigorous movement ________ dancing, jogging, running, swimming to biking up a hill—basically any activity that is able to ________ your heart rate and breathing.

The study found that doing just under 10 minutes of moderate to vigorous physical activity (MVPA) each day led to ________ in study participants’ working memory. In addition, 10 minutes of MVPA had its biggest impact on executive processes such as ________and organization.

The cognitive improvement was ________, but the research found that the benefits grew the more time a person spent ________in the activity of an energetic workout, Mitchell said.

“Now that we don’t monitor participants’ cognition over the course of many years, the results of this study may simply be telling us that those individuals who move more tend to have higher cognition on average,” he said. “While on the other hand, the results do also imply that even making ________ changes to our daily lives can have ________ consequences for our cognition.”

There was bad news as well. Spending more time sleeping, sitting or engaged only in mild movement was linked to a negative impact on the brain. The study found cognition declined 1% to 2% after replacing an ________ portion of MVPA with eight minutes of sedentary (久坐的) behavior, six minutes of light intensity or seven minutes of sleep.

Additional studies need to be done to ________ these findings and to better understand the role that each type of activity plays ________ our cognitive abilities. However, Mitchell said, the study “highlights how even very modest differences in people’s daily movements— less than 10 minutes— can be linked to the ________of quite real changes to our cognitive health.”

7 . One of the presents in my house this Christmas was a late 18th-century volume of the Encyclopaedia Britannica (大英百科全书). It is a window into the discoveries and thinking of the time. The encyclopaedia is an entertaining reminder of how _______ some of our current truths are bound to be. Certainties in areas we haven’t yet understood will look just as ridiculous as some of these in centuries to come. And one of those we are still remarkably _______ is the effect of food and exercise on our bodies. We’re surrounded by confident _______ on how to eat, how to avoid or reverse obesity (肥胖), and yet the advice seems pointless while the world gets fatter. Much of what we think we know is a pile of assumptions rather than _______ .

Our confusion is the theme of Spoon-Fed, a book by one of Britain’s leading nutrition researchers, Tim Spector of King’s College London. Its subtitle is: “Why almost everything we’ve been told about food is wrong.” It is a call for us to _______ more.

One by one Spector offers answers to recent food _______. Coffee can save our lives, he says. Three to four cups a day reduces the risk of heart disease and may cut the risk of death by 8 per cent. Butter does not damage our hearts, Spector argues, and salt is vital. Eggs have gone “from heroes to villains and back again”. Don’t say no to all red meat on _______ grounds; occasional small quantities of high-quality unprocessed meat provide important vitamins and iron and are “probably good for you“. Exercise is so good for longevity and happiness that it should be considered our No 1 drug, but the one thing for which it’s _______ useless is losing weight. Vitamin pills are a multibillion-pound industry with almost no proven _______ but which can cause real harm. Even vitamin D, which Spector used to study and believe in, he now _______.

Spector also offers more than a set of currently _______ tips. The science of nutrition has not been solved by him, as he would be the first to admit. His most _______ point is that there is no one size that fits all. Our bodies are complex, and our reactions are _______: yet nobody wants to pay for the research that might explain why.

Some combination of food choices, genes, environment and the chemical reactions generated by our microbiome — the unique microbe (微生物的) combinations in our body ― yes different _______ for each of us, leaving some lean and two thirds of us too fat. This is the territory Spector wants to explore further and which might just allow us to _______ the global trend to obesity, with all the risks we’ve witnessed this year.