Laziness and willingness to exercise may not just be down to the brain. A new study has found that a key gene in the body could play a significant role in providing energy and motivating people to exercise more.  

Researchers at McMaster University in Canada, have found people missing certain genes that control muscle protein could be more susceptible to becoming lazy and lethargic.

In an experiment carried out on mice, researchers saw that removing genes that control AMP-activated Protein Kinase ( AMPK), an enzyme produced while exercising, left the mice more weak and unable to run as fast as their counterparts who had the gene.

Although mice generally like to run, the researchers found that there was a significant difference between those who had the gene and other who lacked it.

While the normal mice could run for miles, those without the genes in their muscle could only run the same distance as down the hall and back, Gregory Steinberg, associate professor of medicine in the Michael G. DeGroote School of Medicine and Canada Research Chair in Metabolism and Obesity, said.

The study found the mice without AMPK genes had lower levels of mitochondria and their muscles did not take glucose as efficiently when they exercised.

According to Steinberg, when you exercise you get more Mitochondria and their muscles did not take glucose as efficiently as they exercised.

As we remove activity from our lives due to emerging technology, the base level of fitness in the population is going down and that is reducing the mitochondria in people's muscles, he said.

The research is important for those who find it difficult to exercise, especially though overweight or with other health problems, although results of studies on mice are not always reliable when applied to humans.