Spas. Spas. Spas. First, a question for you: What is a wellness center? Here in the US, virtually every “fitness” center has now become a “wellness” center. . First, a question for you: What is a wellness center? Here in the US, virtually every “fitness” center has now become a “wellness” center. First, a question for you: What is a wellness center? Here in the US, virtually every “fitness” center has now become a “wellness” center.