Task: Explanation
Input (English): Chinese poles are vertical poles on which circus performers climb, slide down and hold poses. The poles are generally between 3 and in height and approximately 2 to in diameter. Some poles have a slightly larger pole that rotates around the static central pole using ball bearings. This rotating pole allows a performer to spin on the vertical axis, giving a performer the ability to incorporate rate of spin into what would otherwise be static moves. Bringing the body closer into the pole causes the performer to spin faster. A few Chinese pole tricks have been incorporated with pole dancing techniques. Question: Chinese poles have been used for the dancing that has recently gained popularity as a mainstream form of what activity? Answer: fitness
Output (English):  A few Chinese pole tricks have been incorporated with pole dancing techniques.