Final answer:
In wheel pose, to deepen the back bend, focusing on the hip flexors and shoulder girdle helps to achieve a more extended front body stretch and a fuller spinal arch.
Step-by-step explanation:
To deepen the back bend in a wheel pose, one should focus on deepening the stretch of the hip flexors and the shoulder girdle. The wheel pose, also known as Chakrasana or Urdhva Dhanurasana in yoga, requires flexibility and strength in various parts of the body.
To enhance the stretch in the back bend, practitioners often work on relaxing and lengthening the hip flexors, which can help to extend the front side of the body more, and also focus on opening the shoulders to allow a greater range of motion and promote a fuller arch in the spine.