I Have a Question

why do people like to be so repetitive? i just got a job in a calling center and im going thru training and my coworkers like to go back and forth in their chairs over and over again, or their legs over and over again, or they shake their legs for hrs, i find it really hard to learn not to mention the repetitiveness can drive me crazy, are they on some kind of meds that make them do it or what, i could understand it if they had parkinsons but im trying to learn and i cant, and dont say switch seats cause i get the same thing elsewhere, saying anything dont help, they just do whatever they want anyways and in calling centers its not like you can take the work home and study it there so why do they do it? i find it very annoying when im trying to learn, any suggestions?