When you're at the gym on a treadmill, it's tough to find the motivation to keep at it.
Well, how's this for a kick in the pants: If you don't keep running on that treadmill, the entire gym will go dark, the TVs will shut off, the fans will stop and you'll be left in terrifying, overheated darkness without any Friends reruns to help distract from the searing pain in your hamstrings.
That's the drill at Green Microgym in Portland, Oregon. It's a fitness centre where the members' workouts power the entire building. The gym's owner invested in special workout equipment fitted with generators.
So the more you pedal on the stationary bike, the more kinetic energy you generate. In turn, that energy keeps the lights, fans and TVs running. Apparently, this green approach has slashed the gym's energy costs by more than half...