Hip bridges: Engage your abdominals and pelvic floor before you start to bridge up, then bring the hipbones up to the sky. Then hollow out even more and really engage the pelvic floor. Then slowly lower your back to the mat, starting with your upper back, middle back, then lower back. Once you reach the mat, you can release your pelvic floor, and then re-engage as you do this move again.
Your pelvic floor is the group of muscles and ligaments in your pelvic region. The pelvic floor acts like a sling to support the organs in your pelvis — including the bladder, rectum, and uterus or prostate. Contracting and relaxing these muscles allows you to control your bowel movements, urination, and, for women particularly, sexual intercourse.
The pelvic floor muscles support various pelvic organs, including the bladder, prostate, rectum, and female reproductive organs. The muscles themselves are also involved in the functioning of the urinary and anal sphincters. When they are functioning normally, you are able to control your bowel and bladder movements by contracting and relaxing these muscles.