This too is genetic- voluntary activity, like daily exercise, is genetic and can be passed down to successive generations, according to biologists at the University of California, Riverside.
While working on mice in the lab, they found that activity level can be enhanced with "selective breeding" - the process of breeding plants and animals for particular genetic traits.
AdvertisementTheir experiments showed that mice that were bred to be high runners produced high-running offspring, indicating that the offspring had inherited the trait for activity.
"Our findings have implications for human health. Down the road people could be treated pharmacologically for low activity levels through drugs that targeted specific genes that promote activity.
Pharmacological interventions in the future could make it more pleasurable for people to engage in voluntary exercise. Such interventions could also make it less comfortable for people to sit still for long periods of time," said Theodore Garland Jr., a professor of biology, whose laboratory conducted the multi-year research.
In humans, activity levels vary widely from couch-potato-style inactivity to highly active athletic endeavours.
"We have a huge epidemic of obesity in Western society, and yet we have little understanding of what determines variation among individuals for voluntary exercise levels," said Garland.
The study is an example of an "experimental evolution" approach applied rigorously to a problem of biomedical relevance.
Although this approach is common with microbial systems and fruit flies, it has rarely been applied to vertebrates due to their longer generation times and greater costs of maintenance.
The results of such studies can inform biologists about fundamental evolutionary processes as well as "how organisms work" in a way that may lead to new therapeutic strategies.
The study appears in the Proceedings of the Royal Society B.