Avoid pain and muscle strain by ignoring some of the drastic measures you will see dancers do.
Do not put your toes under the piano, for example, and pull your knees straighter. You are heading for injuries.
Couple of Quick Stories...
Many years ago an artist friend, Vone Deporter and I would do yoga together a couple of times a week in the National Ballet School, in the evenings. We would play some relaxing music and do our own flexibility exercises.
Over the weeks, I felt more flexible, slightly, and got good results, experienced less aches and pains, and overall tension.
I used yoga to stretch the ballet way - forcing every position and deep breathing to distract myself from the pain. I thought I was getting into much better positions.
Vone did her stretching exercises the gentle yoga way. She picked a few yoga positions and stretched comfortably with a stretchy feeling, but no pain. A few weeks later her positions were drastically more flexible than mine. She had no workout routines, no warm up routines, she'd just show up and do it.
That does not seem fair! I thought I was working much harder. But that was the way I was trained. Take it to the limit.
In recent years much that has been written by dancer/dance medicine specialists who have a very different view on how dancers should treat their bodies. How to stretch the foot and ankle joints to improve the curve that is part of ballet fashion, is important.
I remember watching Swan lake with Vone. Karen Kain was performing. Vone leaned over and whispered "What's wrong with her feet?" Huh? What ballet student would not like to have those banana feet?
It's a matter of perspective!
So - what is safe stretching for the top of the arch curve, the instep?
Author Deborah Vogel describes how to relax and knead out muscle tension down the front of the calves to the ankle area, using a Spaulding ball. This is a small,dense, high bounce sports ball. If you sit down on your feet, you can roll the ball under the top of your calf muscle, below the knee joint. You will feel some very tender spots where the muscle is especially tense.
If you lean into the ball on those spots, you will feel some release there. Don't push too hard, because you can do this every day, and gradually condition the muscle.
Working your way down the leg, you can knead and massage tension out of the muscles, which will allow more flexibility at the ankle joint.
Staying in this position (or stretching out for a few minutes if your feet are going to sleep) you can now slide your hand under one knee, and gently raise the lower leg up.
Make sure your ankle is in a straight line, not sickled in or out. You will feel a stretch along the arch curve. Hold the stretch, relax and repeat 10 times, each side, every day.
This is a gentle stretch that produces results. You can also put the Spaulding ball just lower on the foot than the tops of the metatarsal joints, and gently lean into it for an extra stretch.
None of this should produce pain. Look at an x-ray of the human foot and the many tiny foot bones. These bones and the soft tissues supporting them need to be treated gently in between your ballet classes. They are tough, but as you push them as far as they can go every day in the ballet studio, they deserve rest and care.
With these two exercises you can increase flexibility, avoid muscle sprain and foot injuries, and improve your look in pointe shoes.
For an excellent pointe shoe fitting guide, get your dancing daughter a copy of The Pointe Book.