A BREAKTHROUGH new pill could mimic the health benefits of running - but you don't even have to leave the sofa.

Scientists at Aarhus University in Denmark developed a drug that they claim can replicate the impact of jogging at high speed for 10 kilometres.

The pill contains a molecule called LaKe that can mimic the effect of exercise on the body's metabolism after fasting - the practice of abstaining from food or drink for a period of time.

Exercise and skipping meals can make your heart stronger and reduces fat levels in the blood, researchers said.

Working out helps to increase levels of lactates and ketones in the body, chemicals which our body's cells use for fuel.

This in turn can increase the production of appetite-suppressing hormones while bringing down levels of fat in the blood.

LaKe contains a chemical fusion of of lactate and ketones.

Prof Thomas Poulsen, from the Department of Chemistry at Aarhus University, said: "We've developed a molecule that can mimic the body's natural metabolic response to strenuous exercise and fasting.

"In practice, the molecule brings the body into a metabolic state corresponding to running 10 kilometers at high speed on an empty stomach," he explained.

"When lactate and ketone levels in the blood increase, the production of an appetite-suppressing hormone increases and the level of free fatty acids in the blood decreases.

"This has a number of health benefits, for example reducing the risk of developing metabolic syndrome."

According to the professor, it's not possible to achieve the same effect through diet alone, since lactate and ketones can't be consumed in high enough quantities without the buildup undesirable by-products such as acid and salt.

This is where LaKe comes in, as the pill contains lactate and ketones without the harmful add ons.

Prof Poulsen said: "We have now created a molecule which allows us to artificially control the amounts of lactate and ketones safely."

So far, the pill has only been tested on rats.

But the first clinical trials in humans are now underway at Aarhus University Hospital.

According to Prof Poulsen, the trials could pave the way for the molecule to become a nutritional supplement if they're successful.

Scientists behind the study - published in the scientific journal: Journal of Agricultural and Food Chemistry - said people who can't follow a strict exercise and diet plan might find it helpful.

Dr Thomas Poulsen, a chemist at Aarhus University who led the research, said: "It can be difficult to maintain motivation to run many kilometers at high speed and go without food.

"For people with physical ailments, such as a weak heart or general weakness, a nutritional supplement can be the key to better recovery."

According to the researchers, LaKe also has potential to ease struggles with concentration and may even be used in the treatment of serious diseases such as Parkinson's and dementia.

These diseases are often characterised by low energy levels in the brain, which inhibit its optimal functioning, he explained.

Prof Poulsen said: "Because lactate can take over the role of glucose in the brain under stressful or traumatic conditions, there have been experiments to increase lactate levels in people with concussion.

"Patients who cannot perform strenuous exercise will benefit greatly from a drug that can boost these levels."