It has become very popular for dancers to stretch intensively before the barre. I often see both professionals and young students doing intensive stretching before class. They do Penché or sit in side and middle split positions. Sometimes they even arrive an hour before their ballet class to work on these stretches.
Ballet stretching should not be done with an external assistance (manpower, use of gravity) . Instead, consider all Barre exercises, such as Plie, Tendu, all the Battenants, a stretches. This kind of stretching (Ballet Barre ) is gentler than stretching that relies on artificial means because your movements are not forced; instead, with controlled stretching, your body is trained to develop both balance and strength simultaneously. This combination of stretching and strength is essential to avoiding injuries, for each dancer can only stretch as far as his or her body allows.
"Research suggests that stretching may not do your body as much good as people thought. After reviewing more than 350 scientific studies, researchers from the Centers for Disease Control and Prevention (CDC) found that stretching may not reduce the chance of injury. If it's athletic performance you're after, don't expect stretching to help you run faster, jump higher, or throw a ball farther, either. Some studies show that stretching may actually slow you down, especially if you do it before you play your sport."
You might argue that ballet is not sport. Ballet may not be sport, but ballet training is still very athletic. Dancers and their teachers want stronger, higher, better performance.
Ballet training history shows that active stretching was not much utilized or popular. For example, in Russia, ballet schools used not to accept children if they had had prior gymnastics training. Special stretching was allowed only in the 5th year of training. Moreover, it was only allowed after barre work.
Intensive stretching before the Barre defeats the purpose of Barre work, and reduces one’s potential to achieve the best result possible. It may even lead to injury.
The importance of training of arms, heads, Epaulment in ballet has been downplayed in recent years. Most attention in training goes to the lower part of the body including turn out, flexibility, and foot arch. As of today, I see a vacuum in the methodology regarding this part of ballet training.
However, the dancer's body should be very well balanced. Control of balance relies on the upper body, thus it is very important to set the proper alignment (posture) of the upper body (head and arm included). Most of the steps in classical ballet are performed in a straight up, standing position. The lower body will follow the configuration of the alignment that is set in the upper body.
Training upper body is very important for the young dancer; it supports entire muscle formation and develops a solid foundation for the ballet dancer. Training without proper arms placement will cause the imbalance in developing of the dancer.