Some key points to focus on as you move from plank pose, Kumbhakasana to downward facing dog pose, Adho Muhka Svanasana are to tighten the quadriceps, pull the navel back and up, lift and articulate from the vertebrae one at a time like a wave moving to the shore, and keep the breath steady and full. There should be an inhalation into Adho Muhka Svanasana and an exhalation into Kumbhakasana. Feel each vertebrae as you move slowly from one asana to the next. Really juice it up!
Mobility of the spine is one of the surest ways to feel good within your body. The spine acts as the main channel for messages to be brought from your brain to the rest of the body. Keeping your spine mobile and fluid allows for a better connection. Flexibility in the spine also allows your body to be a more comfortable vessel. When you are able to move your head around with ease life is easier. One of my favorite ways of warming up my spine gently is by moving from a plank pose, known as Kumbhakasana, to a downward facing dog pose, known as Adho Muhka Svanasana and then back again several times. This also creates a toning and strengthening of the abdominal region and upper body. The release into Adho Muhka Svanasana creates a stretch in the back of the legs and back.
Remember to keep the shoulders stacked over the wrists in Kumbhakasana and to keep the ears in line with the upper arms in Adho Muhka Svanasana with the feet hip to shoulder width apart and the hands shoulder width apart. Enjoy each movement and dive into the suppleness of your spine!