All warrior poses are good for building strength, and heat in the body. They are, therefore, yang poses, versus yin. Reverse warrior, aka exultant warrior, is similar to warrior 2, in that it strengthens the front quads. However with the reverse hold, it also a wonderful stretch to the external obliques and intercostals.
Not surprisingly, there are different modifications. Do what feels best to you. I like to curve my top arm over my head, with the back around curved behind my back. Some place the bottom arm on their extended leg, keeping the top arm lengthened at a diagonal. Always maintain the front knee aligned over the front ankle. Try to stack he hips and shoulders, as if the back were flat against a wall. For those with difficulty balancing, including pregnant women, hold this pose against the wall.
Typically, standing poses are good options for pregnant women. However, Judith Hanson Lasater, author of “Yoga for Pregnancy,” says poses like this can “put a lot of strain on the pelvic floor, and it’s already strained,” says. Therefore, soon-to-be-mamas may choose to imitate this pose, seated on a chair.
As always, consult your doctor, physical therapist or yoga therapist to determine what poses are best suited for you, or what to avoid.