Abstract:
One of the suspected causes of "tennis elbow" (lateral epicondylitis) is the transfer of racket vibrations onto the forearm. Yet, no attempt has been made to study how muscle strength and flexibility relate to vibrations transfered to the elbow of players with (WP) and without (WOP) elbow pain. Twenty-three tennis players (14 WOP and 9 WP) were tested using an ENT RAN uniaxial accelerometer which was fastened to the lateral epicondyle of the humerus. Three, oversized, Dunlop Super Revelation rackets with different grip sizes and equal string tension were used in the study. A ball machine was used to ensure proper ball velocity (11/1 +/-1.4 m/s) and alignment. Each subject performed five off-center (10 cm) and five on-center, static, backhand trials. The anthropometric variables taken were: age, height, weight, grip size, hand size, forearm circumference and length, wrist circumference and range of motion, and grip strength. Desriptive statistics, Pearson Product moment correlations and t-tests for independent means were used to analyze the data. No significant correlations were found other than age between the WP (46) and the WOP (39). The results of this study suggest that anthropometric differences are not a significant factor in the transmission of racket vibrations onto the arm. The magnitude of vibrations may be more the result of racket properties, grip firmness, torques, or impact than body characteristics.