abdulhakeem
03-12-04, 08:11 AM
December 02, 2004
By Sam Lister, Health Correspondent
EXERCISE is promoted as the key to a long and healthy life, but regular work-outs may be a waste of time for those who have the wrong genes.
Some people are predisposed to getting fit but for an unlucky few, even strenuous exercise has no effect on health or the risk of developing diseases such as diabetes.
Claude Bouchard, the chief researcher at Louisiana State University, said that public health campaigns that promote a relentless fitness message were too simplistic.
“There is astounding variation in the response to exercise,” he said. “The vast majority will benefit in some way but there will be a minority who will not benefit at all.”
The latest findings, published in New Scientist, were presented by Dr Bouchard at the Australian Health and Medical Research Congress in Sydney.
In the study 742 people from 213 families were put through a strict 20-week endurance training programme. The volunteers had not taken regular physical activity for the previous six months.
Exercise on stationary bikes was gradually increased so that by the last six weeks the volunteers were exercising for 50 minutes three times a week at 75 per cent of the maximum output they were capable of before the study.
Previous reports indicated there are huge variations in “trainability” between subjects.
For example, the team found that training improved maximum oxygen consumption, a measure of a person’s ability to perform work, by 17 per cent on average.
But the most trainable volunteers gained over 40 per cent, and the least trainable showed no improvement at all.
Similar patterns were seen with cardiac output, blood pressure, heart rate and other markers of fitness. Dr Bouchard said the impact of training on insulin sensitivity — a marker of risk for diabetes and heart disease — also varied, reports New Scientist. It improved in 58 per cent of the volunteers following exercise but in 42 per cent it showed no improvement or, in a few cases, may have got worse.
“It’s negative, but it’s true. Some people slog away and don’t get any improvement,” says Kathryn North, of the Institute of Neuromuscular Research at the Children’s Hospital at Westmead in Sydney.
In the eight volunteers who showed the largest improvement in insulin sensitivity, 51 genes were expressed in muscles at double the levels of the eight people who showed the least improvement, and 74 genes were expressed at half the level.
Many of these genes were a surprise to the researchers as they have not previously been linked to exercise.
“We need to recognise that although on average exercise may have clear benefits, it may not work for everyone,” said Mark Hargreaves, of Deakin University in Melbourne. “Some people may do better to change their diet.”
similar article: Some people are 'immune' to exercise (http://www.newscientist.com/news/news.jsp?id=ns99996735)
http://www.timesonline.co.uk/article/0,,3-1383925,00.html
By Sam Lister, Health Correspondent
EXERCISE is promoted as the key to a long and healthy life, but regular work-outs may be a waste of time for those who have the wrong genes.
Some people are predisposed to getting fit but for an unlucky few, even strenuous exercise has no effect on health or the risk of developing diseases such as diabetes.
Claude Bouchard, the chief researcher at Louisiana State University, said that public health campaigns that promote a relentless fitness message were too simplistic.
“There is astounding variation in the response to exercise,” he said. “The vast majority will benefit in some way but there will be a minority who will not benefit at all.”
The latest findings, published in New Scientist, were presented by Dr Bouchard at the Australian Health and Medical Research Congress in Sydney.
In the study 742 people from 213 families were put through a strict 20-week endurance training programme. The volunteers had not taken regular physical activity for the previous six months.
Exercise on stationary bikes was gradually increased so that by the last six weeks the volunteers were exercising for 50 minutes three times a week at 75 per cent of the maximum output they were capable of before the study.
Previous reports indicated there are huge variations in “trainability” between subjects.
For example, the team found that training improved maximum oxygen consumption, a measure of a person’s ability to perform work, by 17 per cent on average.
But the most trainable volunteers gained over 40 per cent, and the least trainable showed no improvement at all.
Similar patterns were seen with cardiac output, blood pressure, heart rate and other markers of fitness. Dr Bouchard said the impact of training on insulin sensitivity — a marker of risk for diabetes and heart disease — also varied, reports New Scientist. It improved in 58 per cent of the volunteers following exercise but in 42 per cent it showed no improvement or, in a few cases, may have got worse.
“It’s negative, but it’s true. Some people slog away and don’t get any improvement,” says Kathryn North, of the Institute of Neuromuscular Research at the Children’s Hospital at Westmead in Sydney.
In the eight volunteers who showed the largest improvement in insulin sensitivity, 51 genes were expressed in muscles at double the levels of the eight people who showed the least improvement, and 74 genes were expressed at half the level.
Many of these genes were a surprise to the researchers as they have not previously been linked to exercise.
“We need to recognise that although on average exercise may have clear benefits, it may not work for everyone,” said Mark Hargreaves, of Deakin University in Melbourne. “Some people may do better to change their diet.”
similar article: Some people are 'immune' to exercise (http://www.newscientist.com/news/news.jsp?id=ns99996735)
http://www.timesonline.co.uk/article/0,,3-1383925,00.html