Drug may help prevent athletes from 'hitting the wall'
Scientists have found that a drug may give runners, swimmers, and cyclists extra endurance to prevent them from hitting a wall.
In athletic pursuits, the phrase "hitting the wall" is usually related to a pyschological state in which you can't push your body and harder, even if your body wants to.
In a study published by The University of Sydney and the USA's Salk Institute in the journal Cell Metabolism, it's been shown that a drug can help the body's muscles to burn less glucose. This instead leaves it for the brain to keep you pushing forward.
"It turns out that 'hitting the wall' happens when your brain can no longer get enough glucose. At that point, you're toast," says study author Ronald Evans. "We previously believed that training improves endurance because it allows the muscles to more effectively burn fat as an energy source."
However, your brain solely relies on glucose to function, while your muscles can burn either fat or glucose. If you can isolate glucose for sole use of the brain, it can be used most effectively.
The study has found that the gene PPARδ (Peroxisome proliferator-activated receptor delta) activates the pathways involved when athletes undertake endurance training. By stimulating it at molecular level with chemical intervention, the brain can push the body for longer.
This means an athlete could run, bike, or swim for longer before they hit the wall and can't continue.
A small-molecule drug that activates PPARδ not only increases fat oxidation into muscle, but also stops the effects of hypoglycaemia (loss of glucose) to the brain.
The result of this drug – as tested on mice – saw them able to increase their running ability from 160 minutes to 270 minutes straight without any additional endurance training.
"What we illustrate... is that if you want to move the wall, there is more than one way to do so," Evans says.
"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."
The scientists involved in this study recognise that such a drug could be exploited by athletes to gain competitive advantage.