Triangle Pose (Trikonasana) is a fundamental standing posture typically performed during hatha/vinyasa styles of yoga.
The pose itself makes a triangle shape of the legs and is a great stretch for the hamstrings, inner thighs, and side body.
It is both a strengthening and lengthening posture.
Many people think this pose is all about the legs, but it is just as much about the side body, as well. It is important to keep the rib space open and long, even on the underside, to avoid collapsing in the torso. The secret to this is being of the little triangle that occurs under the bottom rib cage and arm!
With this in mind, your pathway to success in Triangle Pose will much more viable.