Both Tennis and Golfer’s Elbow are conditions of the attachments of the wrist flexor and extensor muscle groups respectively. Over use of these muscle groups commonly found with tennis and golf players causes the attachments to become inflamed. With overworked extensor and flexor muscles of the wrist, they muscles become stronger and shorter so that they constantly try to pull away from their attachments even at rest.
By stretching these muscles and working on the upper muscle groups and elbow, the tension on the attachments can be eased, helping to reduce inflammation. Short term use of an elbow strap can help as it creates a false origin for the muscles involved and so take the load off the muscle insertion points.