A busy brain can mean a hungry body．We often seek food after focused mental activity，like preparing for an exam．Researchers think that heavy bouts of thinking drain energy from the brain，whose capacity to store fuel is very limited．So the brain，sensing that it may soon require more calories（卡路里） to keep going，apparentlystimulates bodily hunger，and even though there has been little in the way of physical movement or calorie consumption，we eat．This process may partly account for the weight gain so commonly seen in college students．Scientists at the University of Alabama at Birmingham and another institution recently experimented with exercise tocountersuch immoderately post--study food consumption．Gary Hunter，an exercise physiologist at U．A．B．，oversaw the study，Hunter notes that tough activity both increases the amount of blood sugar and lactate（乳酸盐）-a byproduct of intense muscle contractions（收缩）-circulating in the blood and increases blood flow to the head．Because the brainuses sugar and lactate as fuel，researchers wondered if the increased flow of fuel-rich blood during exercise could feed an exhausted brain and reduce the urge to overeat．Thirty--eight healthy college students were invited to U．A．B．'s exercise lab to report what their favorite pizza was．At a later date，the volunteers returned and spent 20 minutes dealing with selections from college and graduate--school entrance exams．Next，half the students sat quietly for 15 minutes，before being given pizza．The rest of the volunteers spent those 15 minutes doing intervals on a treadmill：two minutes of hard running followed by about one minute of walking，repeated five times．Hunter says，that should stimulate the release of sugar and lactate into the bloodstream．These students were then allowed to gorge on pizza，too．But by and large，they did not overeat．In fact，the the non-exercisers，however，consumed about 100 calories more．The study has limitations，of course．We only looked at lunch，Hunter says； the researchers do not know if the runners consumed extra calories at dinner．They also cannot tell whether other types of exercise would have the same effect as running，although Hunter says they suspect that if an activity causes someone to break into a sweat，it should also increase blood sugar and lactate，feeding the brain and weakening hunger's call．98．According to the passage， ____ may cause many college students to overeat and gain weight．A．a lot of energy-consuming mental activitiesB．numerous physical movements or calorie burningC．failure to resist the temptation of delicious food．D．bodily hunger caused by physical growth99．The underlined word"counter"is closest in meaning to ____ ．A．stimulateB．maximizeC．balanceD．prevent100．What can be inferred from the passage？ ____ A．Running is more beneficial than walking．B．Sweating in exercise can make people hungrier．C．The amount of blood sugar and lactate can affect people's appetite．D．When the brain feels exhausted，people tend to do exercise for relaxation．101．Which of the following statements is FALSE？ ____ A．Mental activities can make people feel hungry．B．Physical exercise can make people refreshed and stay hungry．C．Sugar and lactate can help energize and restore people's brain．D．It's uncertain what types of exercise can effectively feed the brain．

A busy brain can mean a hungry body．We often seek food after focused mental activity，like preparing for an exam．Researchers think that heavy bouts of thinking drain energy from the brain，whose capacity to store fuel is very limited．
So the brain，sensing that it may soon require more calories（卡路里） to keep going，apparently
stimulates bodily hunger，and even though there has been little in the way of physical movement or calorie consumption，we eat．This process may partly account for the weight gain so commonly seen in college students．
Scientists at the University of Alabama at Birmingham and another institution recently experimented with exercise tocountersuch immoderately post--study food consumption．
Gary Hunter，an exercise physiologist at U．A．B．，oversaw the study，Hunter notes that tough activity both increases the amount of blood sugar and lactate（乳酸盐）-a byproduct of intense muscle contractions（收缩）-circulating in the blood and increases blood flow to the head．Because the brain
uses sugar and lactate as fuel，researchers wondered if the increased flow of fuel-rich blood during exercise could feed an exhausted brain and reduce the urge to overeat．
Thirty--eight healthy college students were invited to U．A．B．'s exercise lab to report what their favorite pizza was．At a later date，the volunteers returned and spent 20 minutes dealing with selections from college and graduate--school entrance exams．Next，half the students sat quietly for 15 minutes，before being given pizza．The rest of the volunteers spent those 15 minutes doing intervals on a treadmill：two minutes of hard running followed by about one minute of walking，repeated five times．Hunter says，that should stimulate the release of sugar and lactate into the bloodstream．These students were then allowed to gorge on pizza，too．But by and large，they did not overeat．In fact，the the non-exercisers，however，consumed about 100 calories more．
The study has limitations，of course．We only looked at lunch，Hunter says； the researchers do not know if the runners consumed extra calories at dinner．They also cannot tell whether other types of exercise would have the same effect as running，although Hunter says they suspect that if an activity causes someone to break into a sweat，it should also increase blood sugar and lactate，feeding the brain and weakening hunger's call．
98．According to the passage， ____ may cause many college students to overeat and gain weight．
A．a lot of energy-consuming mental activities
B．numerous physical movements or calorie burning
C．failure to resist the temptation of delicious food．
D．bodily hunger caused by physical growth
99．The underlined word"counter"is closest in meaning to ____ ．
A．stimulateB．maximizeC．balanceD．prevent
100．What can be inferred from the passage？ ____
A．Running is more beneficial than walking．
B．Sweating in exercise can make people hungrier．
C．The amount of blood sugar and lactate can affect people's appetite．
D．When the brain feels exhausted，people tend to do exercise for relaxation．
101．Which of the following statements is FALSE？ ____
A．Mental activities can make people feel hungry．
B．Physical exercise can make people refreshed and stay hungry．
C．Sugar and lactate can help energize and restore people's brain．
D．It's uncertain what types of exercise can effectively feed the brain．