Although sedentary behaviour may be an evolutionarily selected trait, it is still important to try to be physically active, says a new study conducted at the University of Jyväskylä, Finland. Researchers have shown for the first time that a genetic predisposition to sedentary behaviour is associated with a higher risk of developing the most common cardiovascular diseases. A high genetic predisposition to sedentary behaviour can increase the risk of cardiovascular diseases by up to 20%.

Genetics are known to be associated with both cardiovascular diseases and low levels of physical activity. For the first time, researchers of the University of Jyväskylä's Faculty of Sport and Health Sciences have investigated the association between genetic predisposition to sedentary behaviour and cardiovascular diseases. The unique genome and health data of about 330,000 Finns from FinnGen were used in the research.

Genetic predisposition can be determined using modern genome-wide polygenic scores. The researchers developed a polygenic score to describe genetic predisposition to leisure screen time, the most common type of voluntary sedentary behaviour. The polygenic score was used to investigate the association between genetic predisposition to sedentary behaviour and the incidence of all cardiovascular diseases, hypertensive diseases, ischaemic heart diseases, such as myocardial infarction, as well as cerebrovascular diseases. The analyses were repeated in a separate reference group, which consisted of about 35,000 Norwegians.

"We found that genetic predisposition to sedentary behaviour increased the risk of cardiovascular diseases almost equally in both population samples," says Postdoctoral Researcher Laura Joensuu from the Faculty of Sport and Health Sciences of the University of Jyväskylä. "People with the highest predisposition to sedentary behaviour accumulated about half an hour more daily sedentary time and had about a 20% higher risk of developing the most common cardiovascular diseases, compared to those with the lowest genetic predisposition"

It is worth getting moving, even if you feel lazy

Sedentary behaviour may be a trait selected by evolution. Paleoanthropologists have previously argued that physical activity has long been a survival need in human history, which is why humans would not have evolved to move voluntarily. Although the evidence is still mainly theory-based, human genetics may regulate physical activity behaviour and underlie the commonly observed phenomenon of physical inactivity in the population.

"Our results support previous theories that the human trait to be sedentary has a genetic basis and illustrate its health effects," says Joensuu, "and these findings should be taken into account when promoting the health of the population.

"The feeling of not having the energy to exercise can be completely normal. However, since physical activity has positive effects on our overall well-being, it's important to ignore these types of negative feelings."

"We should better encourage physical activity in our society. One effective way to do this is by fostering a sense of community and the joy that comes with physical activity."

The study was published in the world's leading sports medicine journal, the British Journal of Sports Medicine. The first author of the study, Postdoctoral Researcher Laura Joensuu, is a member of the GenActive research group of the Faculty of Sport and Health Sciences, University of Jyväskylä. The GenActive group investigates genetic and lifestyle factors that predict biological ageing, health and functional capacity. The group is led by Elina Sillanpää, Associate Professor of Health Promotion.