The spinning disc is the ultimate way to level up your Ninja game. It’s like a merry go round for your hands. 
If you want to master this obstacle, you must understand centrifugal force:
𝐹= 𝑚𝑣(squared) / 𝑟, where 𝐹 is force, 𝑚 is mass, 𝑣 is velocity, and 𝑟 is radius.