Sports Psychology and Sports Hypnosis are difficult to separate as they both work with behaviour and the unconscious mind to varying degrees.
The key difference is that Sports Psychology aims to make small changes and improvements over a long period, whereas Sports Hypnosis achieves major changes over a far shorter time scale.
Sports Hypnosis is far more effective in getting rapid results. In fact a lot of the most effective techniques (such as visualisation) used in Sports psychology are themselves forms of hypnosis, even though many Psychologists are unaware of the fact.
Sports Hypnosis works directly with the subconscious mind, the part of the mind that controls our actions and behaviours, so changes are affected quickly. This is extremely important to sports people who need to achieve “the zone” when competing.