There can be many problems, not only weak inner core muscles, resulting in not being able to keep yourself in the ideal body position. (personaltraining4u.net)
Similar to the exercise routine found in my book, Lady Bits, the exercises in the video above are designed to strengthen the deep inner core muscles including the pelvic floor, glutes, deep abdominals, and deep back muscles. (femfusionfitness.com)
On top of that (it will hurt if you're a big fan of the core stability isolation training) there is no better way to train inner core muscles than doing these 3. (personaltraining4u.net)