Exercise pill...Exercise in a pill? This may sound like a premise too good to be true, and something that will have government officials and personal trainers shaking their heads in despair. However, the results of two connected studies published in Nature Medicine suggest that we may be able to soon receive the health benefits from exercising – without having to move a muscle or break a sweat! Researchers at the Scripps Research Institute in Florida formulated a compound in 2012 which once injected into obese mice, actually amplified activation of ‘REV-ERB’ – a protein which can help to control animals’ circadian rhythms and internal biological clocks. These mice were found to lose weight and improve cholesterol levels despite being on a high fat diet. To their amazement, the researchers discovered that the mice injected with the compound started to use up more oxygen on a daily basis and expend roughly 5% more energy than the untreated mice, even though they were less active than the untreated mice. Generally, the treated mice had actually become lazier than pre-injection and it seemed the compound was providing them with exercise without any effort being input. Working with researchers from the Pasteur Institute in France, Scripps scientists decided to conduct further test to try and find out more information about how the compound worked inside of muscles to generate this invisible exercise. It was clear the drug was boosting potency of the REV-ERB protein, but scientists were puzzled as to what role REV-ERB had inside the muscles. Therefore, a strain of mice were analysed – all of whom were unable to express much REV-ERB in their muscle cells, being referred to as ‘anti-athletes’. A common indicator of regular aerobic exercise is the fact that there is usually a better vigour and quantity of the mitochondria. These are cellular structures aiding the production of energy whilst oxygen is consumed. The anti-athlete animals’ muscles had a staggeringly low number of mitochondria. This means they became exhausted way before other mice, with poor endurance and a maximal oxygen capacity of approximately 60% less than what would be considered normal. However, in another part of the experiment, the scientists added their compound to isolated muscle cells from these particular mice.  The cells started to generate significantly more REV-ERB and thus began to generate new mitochondria in addition to improving/strengthening the ones already present. Then it was sedentary mice that were given the compound to test them with a higher amount of REV-ERB than what could be considered normal. After being set free onto small treadmills, these mice ran “significantly longer both in time and distance” than the untreated animals, the authors wrote, despite no previous training. Co-author Dr Thomas Burris, chairman of the department of pharmacological and physiological science at St Louis University School of Medicine says there is a possibility in the future that this ‘exercise pill’ might be able to especially help the disabled or can’t otherwise exercise, to enjoy the health benefits of endurance without the exertion. However, don’t cancel your gym membership just yet. Dr Burris stresses the core aim of his and other similar research is to help those who are unable to exercise, for whatever reason, not those who simply cannot be bothered. He says: “Exercise has so many health benefits” and “no drug can” recreate all of them. Activities such as swimming and lifting weights will never be fully reduced to tablet form, and exercising helps to release endorphins - the body’s natural feel-good chemical , and decreases stress hormones such as cortisol.