Triangle Variation in Chair
Sit on chair with a tall spine. Separate your feet and knees as wide as you can comfortably. On an inhalation lengthen your spine (sit up taller) and on an exhalation bring your left forearm onto your left thigh as you stretch your right arm up to the left.
Inhale and come back to a tall spine, exhale and come down to the right side.
Coordinating your movement with your breath; come into the side stretch on each side three times before holding each side for 3-6 breaths. As you are holding the pose on each side, soften and relax within the effort of the pose. There should not be any straining or pain, just a gentle stretch. If there is straining or pain or if you can not maintain a slow relaxed breath, then you have pushed too far into the pose.
When you are done, sit with a tall spine and rest for a few moments before resuming your activities so that your spine can come back to neutral. If you feel tension in your back after this, then bring your knees together and fold forward and/or do the cat/cow variation. Both of these counterposes will release tension from your lower back and bring your spine back to neutral.