London: Wonder why you do not feel fit despite spending hours on treadmill? Blame your genes.
A new study by researchers from 14 institutions around the world found that one in every five has inherited `unfitness genes` that affect our ability to burn off fat through exercise.
The finding paves the way for a simple blood test that would tell a person whether he has inherited `unfitness genes` or not.
As part of the study, the team recorded the improvements in the aerobic fitness -- change in amount of oxygen they took in -- of over 600 people who regularly cycle, the Daily Mail reported.
They also studied their DNA and identified 30 genes which affect oxygen uptake.
The scientists found that any variation in 11 of these 30 genes was closely correlated with changes in aerobic fitness after cycling, according to the report in the Journal-of
Applied Physiology.
Around one in five of those tested had a combination of genes that meant their oxygen uptake hardly changed, despite weeks of fast pedalling.
"The change in aerobic fitness was so small you could miss it," said researcher James Timmons. "People will say that we only looked at one measure of fitness and there are other benefits of aerobic exercise. That is absolutely true but this is the hard and fast one that really predicts death," Timmons added.
PTI