Downward Facing Dog is a pinnacle posture in yoga but there a lot of misconceptions about the posture.
One of the biggest myths in Downward Facing Dog is that your heels have to touch the floor. But they do not.
For some, the heels might naturally touch the floor but for many, it's actually better when you’re in Down Dog to bend the knees slightly to create a greater length in your back. Bending the knees can actually keep the heels from touching the floor. But a straight back is more important than the heels touching the floor. You do want the energy of the heels are going down to the floor but they do not have to touch.
If your heels are touching the floor, it's actually possible that you have your hands and feet too close together which will create more of a forward fold posture than the V-shape that is typical in downward facing dog.
This is just one small little part of down dog that will help you feel good in the posture.
I want you to try it the next time you’re in the pose. Bring awareness to the position of the knees and the placement of your feet and how close the heels are to the floor.