The bandhas (mula bandha specifically) are perhaps the most difficult aspect to grasp in the practice of Ashtanga Vinyasa Yoga. For me personally, I think I know what they are. But then I look back at my little life as an Ashtangi, amazingly at 11 years now, and realize, I thought I knew what they were 10 years ago. Then just 5 years ago I understand them even more differently than I do today. My experience of them has changed over the years and will continue to as I’m guessing your experience of them will.
In the last piece about mula bandha and its relationship to the pelvic floor muscles I alluded to the muscle that might be most associated with uddiyana bandha. Well, here we are continuing down the path to try and bridge the subtle and gross of our bodies as best we can.
As a preface, there was an original question asking if someone could explain what nutation and counternutation actually were and how it might relate to backbending type postures such as ustrasana, kapotasana, and urdhva dhanurasana.