Couch potatoes can't help being lazy – they were BORN that wayNot getting enough exercise was previously thought to be down to simple lazinessBut new study shows that genes play major role in deciding whether we enjoy a trip to the gym or not
Daily Mail Reporter
15:21 GMT, 9 April 2013
21:31 GMT, 9 April 2013
Laziness may be written into our DNA, say scientists.
Genetic traits may predispose some people to being less motivated for physical hard work, a study suggested yesterday.
Researchers were able to selectively breed rats that were either extremely active or extremely lazy and they say this indicates that genetics play a role in our willingness to exercise.
Preferring to sit in front of the television rather than take a jog is not down to laziness, says an American study
Co-author Professor Frank Booth, of
Missouri University, said: ‘We have shown it is possible to be
genetically predisposed to being lazy.
‘This could be an important step in identifying additional causes for obesity in humans.
‘It would be very useful to know if a
person is genetically predisposed to having a lack of motivation to
exercise, because that could potentially make them more likely to grow
The study, published in the American
Journal of Physiology, measured how many times each rat voluntarily went
on a running wheel during a period of six days.
In the genes: Some of us are programmed to be less active
The top 26 runners were then bred with each other and the same process was applied to the 26 laziest rats.
After the breeding programme had been
repeated for ten generations, the line of active rats ran ten times more
than the line of lazy rats.
The researchers studied the levels of
mitochondria in the rats’ muscle cells, compared body composition and
conducted genetic evaluations.
Co-author Dr Michael Roberts said:
‘While we found minor differences in the body composition and levels of
mitochondria in muscle cells of the rats, the most important thing we
identified were the genetic differences between the two lines.
‘Out of more than 17,000 different
genes in one part of the brain, we identified 36 genes that may play a
role in predisposition to physical activity motivation.’
The researchers now plan to explore the effects of the identified genes on humans’ willingness to exercise.