When you practice Janu Sirsasana as a twist rather than a forward bend, it can further educate you about the mechanics of rotation. (yogajournal.com)
However, don't take up the practice of Sirsasana after you become pregnant. (yogajournal.com)
Inversions, such as Sirsasana (Head Stand) only received MET values up to 2.5 — although the studies did not measure some of yoga's most difficult poses, such as Bakasana (Crow) or Adho Mukha Vrksasana (Hand Stand). (health.com)