This finding will leave you breathless. A physiology professor at the University of Milan concluded that four men running, walking and riding bicycles emit more carbon dioxide than hybrid cars. He also compared it to gas and diesel cars, which beat the men in terms of carbon emissions.

Of course the research carried out by Alberto E. Minetti is just illustrative of how clean hybrid cars have become. As one commentator questioned in the Scientific American, where the original article appeared, "does the carbon dioxide total with each vehicle used include the CO2 released by the four men sitting at rest within the vehicle? From the earth's point of view, it should."

Nor did the study take into account the C02 produced during the manufacturing of the car. But then, we could also factor in the food consumed by the runners in order to get the energy to do all this running. Or, as Dvice notes, cars can be turned off and temporarily stop emitting carbons, while humans can't.

As Dvice also highlights, the point of the comparison is to show that vehicles running on green technology have come a long way and are definitely leaving a lighter footprint on the planet. That's good news. And you can start breathing again...