This varies from person to person and there is no unified standard. As long as the penis is inserted into the vagina and the wrapping force is not strong, it can be considered to be loose. If the vagina is loose, you can sit and do levator exercises without any problem. Just inhale and tighten the anus, which feels like lifting the anus. Then relax again, and repeat. Practice every day. Helps restore vaginal relaxation.

I hope you can adopt it