thedrifter
09-24-08, 06:59 AM
Vital signs: Exercise-induced asthma linked to less sweat
By Eric Nagourney
Tuesday, September 23, 2008
Dr. Warren Lockette, Dr. Karen Faith Berman
People who suffer from a form of asthma caused by exercise appear to produce less sweat, saliva and tears than people without the problem, researchers say. The findings may shed light on a condition known as exercise-induced asthma, which occurs in some people when they exert themselves in cold air.
Writing in the September issue of Chest, the researchers, led by Dr. Warren Lockette of the Naval Medical Center in San Diego, noted that the low levels of moisture found in cold air appeared to play a role in exercise-induced asthma. As the airways dry out, they become inflamed. Lockette said the condition was fairly common among top athletes.
The researchers examined U.S. marines who came to the naval center because they appeared to have the problem. The researchers measured their levels of sweat, saliva and tears, and found lower levels in those volunteers with exercise-induced asthma. It may be, the researchers said, that the same body mechanism that leads people to produce less sweat and other fluids leads to their having drier airways.
AS PEOPLE AGE, THE THRILL IS (ALMOST) GONE If opening presents seems less exciting at age 60 than it did at age 10, the explanation may lie in the brain. A study has found that as people age, their brains respond less strongly to rewards. The main difference is in the response of the brain to dopamine, a naturally occurring chemical messenger that plays a central role in the reward system.
Dr. Karen Faith Berman of the National Institutes of Health, an author of the study, said the shifts in brain response might be reflected in the shifts in attitude that accompanied aging. "It may explain anecdotal evidence that people are mellower," she said, "that they may not get the same highs from certain experiences, but they may not get the same lows, either."
The study appears online in The Proceedings of the National Academy of Sciences. The researchers performed brain scans on two groups of volunteers, one in their 60s and the other in their 20s, as they played a computer game resembling a slot machine. The researchers found differences between the groups both when they anticipated winning money in the game and when they actually did so. When a reward was anticipated, the researchers said, three parts of a reward center in the brain lighted up in the younger group, but only one in the older group.
Ellie
By Eric Nagourney
Tuesday, September 23, 2008
Dr. Warren Lockette, Dr. Karen Faith Berman
People who suffer from a form of asthma caused by exercise appear to produce less sweat, saliva and tears than people without the problem, researchers say. The findings may shed light on a condition known as exercise-induced asthma, which occurs in some people when they exert themselves in cold air.
Writing in the September issue of Chest, the researchers, led by Dr. Warren Lockette of the Naval Medical Center in San Diego, noted that the low levels of moisture found in cold air appeared to play a role in exercise-induced asthma. As the airways dry out, they become inflamed. Lockette said the condition was fairly common among top athletes.
The researchers examined U.S. marines who came to the naval center because they appeared to have the problem. The researchers measured their levels of sweat, saliva and tears, and found lower levels in those volunteers with exercise-induced asthma. It may be, the researchers said, that the same body mechanism that leads people to produce less sweat and other fluids leads to their having drier airways.
AS PEOPLE AGE, THE THRILL IS (ALMOST) GONE If opening presents seems less exciting at age 60 than it did at age 10, the explanation may lie in the brain. A study has found that as people age, their brains respond less strongly to rewards. The main difference is in the response of the brain to dopamine, a naturally occurring chemical messenger that plays a central role in the reward system.
Dr. Karen Faith Berman of the National Institutes of Health, an author of the study, said the shifts in brain response might be reflected in the shifts in attitude that accompanied aging. "It may explain anecdotal evidence that people are mellower," she said, "that they may not get the same highs from certain experiences, but they may not get the same lows, either."
The study appears online in The Proceedings of the National Academy of Sciences. The researchers performed brain scans on two groups of volunteers, one in their 60s and the other in their 20s, as they played a computer game resembling a slot machine. The researchers found differences between the groups both when they anticipated winning money in the game and when they actually did so. When a reward was anticipated, the researchers said, three parts of a reward center in the brain lighted up in the younger group, but only one in the older group.
Ellie