You don't know my pain, like day unaware of night's domain. 

Please don't imitate the flexibility training in the video.
This video is for documentary only.
today I am filming my dance class students doing the flexibility stretching under the other teachers' assisting.
cameraman and editor: Henry Boulanger
camera: iPhone 6
Declaiming：
Please don't imitate the training in this video by yourself. The students in the video are professional dancers and have been studying for more than one year. The teachers have more than five years of teaching experience, so they dare to train students like this.
The students in the video are challenging to a higher level of flexibility, so the training of the teachers is more severe. But this kind of training is harmless because the students have already warmed up before the training, the bones and muscles have been totally relaxed, after the training, the students will get the corresponding auxiliary massage to eliminate the muscle pain.
Everyone has limited ability to withstand the pain, so you can see some of the students screaming or crying in the video, and some students are not. but This is good in flexibility training, If it is not painful, that means students have not broken his or her own limit, then he or she will not make progress, and such pain is controllable. also screaming or crying helping them to relieve the pain, then they can hold in that position for enough time, that is the goal when doing the flexibility stretching.

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