has produced a series of exercises using the tongue and soft palate to assist a diver in clearing their ears by these techniques. These recommendations were based on work done at the Médecine du sport, Bd st Marcel, Paris.

With practice it is possible for some people to close the nostrils hands-free by contracting the compressor naris muscles. Some people are able to voluntarily hold their Eustachian tubes open continuously for a period of several seconds