As with the overhand throw, the tennis serve generates considerable angular velocity at the elbow. Kibler indicated that the angular velocity for elbow extension reaches 982°/sec and forearm pronation reaches 347°/sec.47 In their investigation of the effectiveness of arm segment rotations in producing racquet-head speed, Sprigings et al.48 reached conclusions that conflicted with those of Kibler.47 They found that forearm pronation had the fastest rotation of 1375°/sec; however, it ranked fourth in terms of contribution. They concluded that elbow extension did not contribute significantly to the forward speed of the racquet head. Note that this study analyzed only one player, and the authors indicated that the lack of contribution of elbow extension may be due to technical flaws with this player's particular technique. Cohen et al. investigated relationships among anthropometric data, upper extremity strength, and functional serve velocity and concluded that elbow extension torque production was highly related to serving velocity.49 Kibler estimated that the elbow joint contributes 15% of the force produced during the tennis serve.47

During the serving motion, the elbow moves through a flexion range of approximately 100° (from 116° to 20°), but the range of motion during ground strokes is smaller (11° during the forehand stroke and 18° during the back hand stroke).47 Electromyographic activity for muscles about the elbow appears to be lower during the ground-stroke motion than during the serving motion.50 This finding may indicate that during ground-stroke motion, muscle activity stabilizes the elbow and generates velocity during the serve. Morris et al. concluded that high prona-tor teres and triceps activity (more than 60% manual muscle test) plays a significant role in power production for the serve.50

A common interest of researchers and clinicians is the cause of lateral epicondylitis, or tennis elbow, which occurs in 40% to 50% of recreational players.51 It is often thought to be caused by repeated microtrauma and high wrist extensor activity as soft tissues about the elbow dissipate impact forces. As Roetert et al. and Hatze reported, it is estimated that impact forces during the backhand stroke create torques equal to 17 to 24 N-m.51'52 Based on studies of the electromyographic activity of muscles about the elbow during the backhand, the cause of injury appears to be related to stroke mechanics and technique, rather than to high muscle activity. Giangarra et al. compared forearm muscle activity during single- and doublehand backhand strokes and found no difference between wrist extensor activity.53 The authors of this and previous studies concluded that the decreased occurrence of lateral epicondylitis for players using the double-hand technique is attributed to changes in the mechanics of the stroke and the increased ability to absorb the forces created at impact.53'54 Players with a history of lateral epi-condylitis have been shown to have greater wrist extensor and pronator teres activity.55 The increased activity was attributed to abnormal stroke mechanics observed with cinematography that included leading with the elbow, exaggerated wrist pronation, and off-center ball impact location on the racket head (lower portion). As Roetert et al. indicated, the high involvement of the wrist extensors in all types of strokes increases the chances of overload and the potential for injury for this muscular system.51 Improper stroke mechanics exacerbate this problem.

Cure Tennis Elbow Without Surgery

Cure Tennis Elbow Without Surgery

Everything you wanted to know about. How To Cure Tennis Elbow. Are you an athlete who suffers from tennis elbow? Contrary to popular opinion, most people who suffer from tennis elbow do not even play tennis. They get this condition, which is a torn tendon in the elbow, from the strain of using the same motions with the arm, repeatedly. If you have tennis elbow, you understand how the pain can disrupt your day.

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