"just a street with houses, but no fitness center"
The place has gone or never existed. A CoMaps user reported that the POI was visible on the map (see snapshot date below), but was not found on the ground.
OSM snapshot date: 2025-09-06T09:48:08Z
POI has no name
POI types: leisure-fitness_centre
#CoMaps ios

There is a parking here

via StreetComplete 61.3