Fitness course subscription service ClassPass said Wednesday that it would discontinue its unlimited workout option, pulling off a sudden two-step that ignited an insurrection on social media.

ClassPass CEO Payal Kadakia said in a blog post that the unlimited subscription plan was unsustainable despite sharp price increases.

"We simply couldn’t make the plan work for our business," she said, acknowledging that the company's costs escalated when customers took advantage of the option.

The New York-based startup had earned plaudits for providing a one-stop shop for fitness enthusiasts interested in trying out various exercise classes at different gyms and dance studios, all for a set monthly fee. Classes included Pilates, cycling, Zumba and strength training.

The venture-capital-backed company even became one of USA TODAY's 10 finalists for its Small-Business Innovator of the Year award in 2015.

Remaining monthly options include a five-class plan and a 10-class plan. Pricing varies depending on location.

A ClassPass spokesperson declined to say how many people were enrolled in the unlimited plan.

"The larger majority of our user base is now on" the other plans, "and we have continued to see accelerated acquisition on those plans that outpace unlimited, which gave us the confidence to move away from unlimited," the company said in a statement.

ClassPass subscribers reacted contemptuously.

Kadakia explained the move: "For every class taken, we paid our studio partners. The more classes that were taken, the more we paid. As you can imagine, our business costs increased rapidly. So we raised our plan prices in an effort to compensate – but we tried not to raise them too much. After all, we wanted to remain as accessible as possible. But in some cities, we even had to raise our prices twice in one year, which was awful for our members and painful for my team."