Researchers have identified areas of DNA which may play a part in whether people are physically active or have a more sedentary lifestyle.
How their muscles respond to exercise could explain why some people are less active, say the researchers, who have also described their findings as providing “great leads for further studies”.
The team set out to further the understanding around the biology behind why some people lead more sedentary lifestyles than others.
The international study, which was led by a team from Uppsala University in Sweden, looked at data from more than 700,000 people taking part in 51 studies. This led to them identifying DNA areas linked to how much screen time or physical activity people say they undertake.
- Taste buds influenced by DNA, study finds
- Working from home triggers negative lifestyle choices, study suggests
Ruth Loos, from the University of Copenhagen, said: “We know that people tend to overreport how much time they spend on physical activity, but around half of the DNA regions we identified also show robust associations with physical activity as measured using devices that people wore during daily life. This adds further credibility to our findings.”
The study also revealed that DNA variants linked to screen time are often found near to genes which change activity in skeletal muscle due to strength training, furthering the theory that genes have a role in how active someone is because of how their body responds to physical exercise.
For instance, the researchers identified a DNA variant that modifies the ‘building blocks’ of a protein only found in fast-twitch skeletal muscle fibres.
- Reduce screen time and improve health say experts
- Not getting enough sleep makes us selfish and lonely, says new research
Co-author Andrew Emmerich explained: “Our results show that this change results in more elastic muscle fibres that can deliver less force, but are likely less susceptible to exercise-induced muscle damage.
“We think that this reduced risk of muscle damage after exercise makes it easier for people to have a more active lifestyle.”
Lead author Marcel den Hoed said: “We cannot currently claim that these 46 genes cause someone to be more or less physically active in daily life, but they provide great leads for further studies.
“Perhaps in the future it will even be possible to trigger the beneficial effects of physical activity without the need to be physically active.”
Their findings also demonstrated that less time spent on screens and being more active reduced the risk of obesity.
The study has been published in the journal Nature Genetics.
