Scientists have developed an “exercise pill” that boosts athletic endurance by 70 per cent without breaking into a sweat.
The drug improved stamina and weight-loss in inactive mice by mimicking the effect of a hard workout.
Researchers from the Salk Institute, in California, gave one group of inactive mice a drug for eight weeks.
Another group was not given the drug.
Both groups were subjected to treadmill tests to see how long they could run until exhausted.
Mice in the control group ran for 160 minutes and those on the drug for 270 minutes – 70 per cent longer.
Study leader Weiwei Fan said: “You can improve endurance to the equivalent level as someone in training, without all of the physical effort.”
Humans and mice are able to exercise until they “hit the wall” – that is when blood sugar levels fall so low that the brain and body are now longer able to function properly.
That is experienced as mental and physical fatigue.
Muscles are able to get their energy from glucose – a type of sugar – or body fat but the brain relies solely on glucose.
Regular training boosts endurance by encouraging the body to run off fat, therefore preserving sugar for the brain.
The drug used by scientists on the mice – known as GW1516 – was found to have the same effect.
Drug companies are now interested in using the research to develop clinical trials for humans.
Ronald Evans, who also worked on the study, said: “It turns out that “hitting the wall’ happens when your brain can no longer get enough glucose. At that point, you’re toast.
“What we illustrate in this study is that if you want to move the wall, there is more than one way to do so.
“The standard method is to train. You will improve a bit with each run.
“But we’ve shown improvement can happen without expending the energy that otherwise would be needed to get to this point.
“Exercise is valuable for many different kinds of problems.
“With this research, you can begin to think about how a therapeutic that confers the advantages of fitness could help people gain health benefits.
“The greater potential is essentially unlimited.”
The researchers acknowledged the potential for doping in professional sport but hope the drug will be used primarily for medical reasons.
They say the findings offer hope to people with heart conditions, disabilities or other health issues that prevent them from exercising.
They could get many of the benefits of a run or cycle without having to move.
Source: The Sun Newspaper