Urdhvapadasana is a form of yoga, which is valued as a great abdominal strengthener. Urdhva means up and Padasana means posing with the legs. So Urdhva Padasana means an Upward Feet Pose.

One has to just lie on the back and swing the extended legs across an angle of approximately 90 degrees. The foot is perpendicular t the floor and then comes back parallel to the floor again. It is usually done in the mornings.

Technique :

First, lie on the back side.
Now with the help of the thigh muscles press the back portion of the thighs and the buttocks together such that they press on the floor.
Now stretch the legs upwards at the same time spreading through the toes and the feet.
Now clasp your toes together and try to pull them apart from the thigh region.
Now focus on the sides and stretch such that you are away from the wall.
Focus on the waist and let the sides of the waist go towards the floor. Relax the groin area.
Let the chest area swell and broaden out.
Now let the arms go up along the sides of the ears.
Take a few breaths and stay in this position.
Now breathe out still keeping the buttocks, back on the floor, and slowly lift the heels up an inch.
Hold the position and take several breaths
It is time to exhale so breath out and slowly release your heels again to the wall.
Unlock your toes and now perform the asana with interlocking it the other way.

Benefits Of Urdhvapadasana :
This asana helps in strengthening the abdomen. This also improves your sense of power, focus, and concentration.
When the arms are taken up, they help in increasing the capacity of the lungs thus improving overall awareness.

Important Tips :
The spine has to be straight throughout.
Remember to bend only after exhalation.