Make:

Image from The Green Microgym in Portland

Seems unlikely, but it's good to see CNN writing about even the more green-washed ends of the sustainability spectrum:

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.
...
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.

Later in the article, I think the designer of one of the (partially) human-powered gyms gets it right:

Although he shows enthusiasm for the battery project, Gambarota, who now spends much of his time developing micro wind turbines, is sceptical about the future of human-power on a mass-scale.

He raises doubts about the efficiency of human power and questioned its economic viability.

The average amount of power one person could produce going about normal activities on any given day was about one kilowatt-hour (kWh), which only amounted to about € 0.10 worth of electricity, Gambarota said.

"It's a very good marketing tool for businesses, but in terms of economics it does not make sense at all."

Sounds to me like a dance club would have a greater reduction in carbon emission by providing free admission and a bicycle valet for those who pedal to their evening entertainment...