Utkata = Fierce.
Asana = Steady Pose or Posture.
This posture will strengthen the legs and the core, it will also help to stabalise the ankles.
How to Perform Utkatasana
Begin standing in Tadasana – The Mountain. If it is comfortable join the inside of your feet and legs, if you prefer you can keep a small space between the insides of your feet and legs.
Bend your knees and move your hips back as if you were sitting down on a chair. Draw your lower abdomen in and up to support your lower back. As you send your hips back allow your torso to also hinge forwards, this helps to keep the lower back long (although some schools of yoga also teach this keeping the torso upright.
Send your hips back rather than your knees forward, so that you can still see your toes
Raise your arms up beside your ears and soften your shoulders.
Hold breathing slowly and completely through the nose for 5 – 10 breaths.