LONDON, England (CNN) -- Would you still watch your favorite television program if you had to cycle for an hour before you could view it?

Couch potatoes will be horrified, but fresh advances in human-powered technology -- where users power appliances through their own motion -- could one day see a 'workout-to-watch' scenario become reality.
Human power is rapidly gaining in popularity worldwide as businesses seek 'greener' methods of operating.
The profile of the technology is set to receive a further boost this month when a human-powered gym opens in Portland, Oregon, and again in September when the human-powered 'sustainable dance club', Club Watt, opens its doors in Rotterdam, Netherlands.
Human power is already being used to run the 'California Fitness' gym in Hong Kong, and to power the recently opened 'Club Surya' in London.
iReport.com: Can you predict what the future will be like? Beyond all of this, further concepts have been developed for human-powered 'river gyms' for the waterways of New York. But, how does your sweat and strain turn into power for lights, music and machines?
The general concept is known as energy harvesting, which simply refers to the gathering of energy from one source and applying it to power an object.
Italian inventor Lucien Gambarota, who designed California Fitness's method of storing energy and using it to power lights and music in the gym, told CNN the concept is straightforward. ""One of the oldest types of energy used by people is muscular energy -- so this is nothing new.""
Gambarota said machines such as exercycles created a load, used as a counter-force by means of a resistor.
""I disconnected the resistor and started storing the energy into a battery ... that is then used as power. It was a way to show there can be very simple solutions. It doesn't always have to be high-tech,"" he said.
Portland's 'green' gym will have spinning bikes connected to wind-generator motors. The users should generate enough electricity to power the gym's music system or run personal DVD players on the machines, the gym's manager Adam Boesel predicts.
While harnessing the energy from people working out at a gym seems logical, utilizing the movement of clubbers at dance clubs is a little more complex.
Two methods have developed -- the first of which is piezoelectricity, used by Club Surya, where crystals in blocks under the dance-floor rub together with the assistance of dancers on the floor. This generates an electrical charge which is then fed into batteries.
A second method using wheels to generate energy under a slightly moving floor will be used at the soon-to-be-opened Club Watt. This model involves coils and magnets which move under the dance-floor to create a charge.
Vera Verkooijen, spokeswoman for Sustainable Dance Club, the company which is behind the floor for Club Watt and produces smaller, portable floors, said the human power would be enough to power about 30 percent of the club's requirements.
Verkooijen admitted the first floors were not very efficient, and said the designers were already working on new models to improve the amount of energy captured. ""This is just the first version. We are willing to take it further,"" she said.