Before revision: The idea is that by strengthening your sphincter muscles (eye muscle: orbicularis oculi and mouth muscle: orbicularis oris), the contractions would also strengthen the sphincter muscles in the pelvic floor.
After revision: The idea is that by strengthening one's sphincter muscles (eye muscle: orbicularis oculi and mouth muscle: orbicularis oris), the contractions would also strengthen the sphincter muscles in the pelvic floor.