Utthita Trikonasana (Extended Triangle Pose): This pose strengthens the legs, and ankles. Stretches groins, hamstrings, hips, opens the
chest and shoulders for deeper breathing. Also activates the spine improving it's flexibility. Relieves backache, and helps reduce stiffness in the neck, shoulders and knees.
To begin Utthita Trikonasana have the feet about three to four feet apart with straight legs. Your working up to a distance of the length of one leg between the feet and with flexibility this distance may increase. Place a block beside the ankle inside or outside, if your more flexible place on the inside. Keep your hips and chest facing the long side of the mat. Raise your arms parallel to the floor. Turn your right foot to the right pointing the toes. Turn the left foot slightly to the right up to 30 degrees to the front. Press your right heel and big toe to the floor.
Get height in the spine and on your next exhalation extend to the right like someone is pulling the right hand keeping the torso as one unit not bending laterally in the spine, to help this let the hips tilt to the right like a teapot. When you've reached as far as you can comfortably go, exhale and drop the right hand to your leg, block or floor while the left hand and arm points to the ceiling aligned above the shoulders. Pull the tailbone into your body. Keep the left hip and shoulder pulled back to the long side of the mat behind you. Turn your head and look up at your left thumb if you can do so comfortably. Readjust your weight on both heels. Breathe evenly with a long breathe not to deep and hold the pose 15 - 30 seconds. If your tight 15 seconds is plenty and if flexible you can hold for a minute or longer if you choose. I hold the pose 40 to 60 seconds. Repeat on the other side.
Added adjustments: Do not lift the head, push the right shoulder into the body, and open the armpits. Keep the arms fully extended.
Go slow and take your time. It will take months or longer to understand the location of where all the parts of your body are in the pose. Keep working towards alignment.
Healthy & Happy