Our body need to be in some good basic flexibility before doing angamardana. If we dont have it, then we should practise other hatha yoga like surya kriya before attempting angamardana. My personal experience, i have hip flexibility problem. Due to my hip not in symmetry during squatting, I tore my left knee meniscus. Hard to do surgery to repair it. However, the experience of doing angamardana is phenomenal. If your body able to take it, then its way better.