STRETCH-SHORTENING DRILLS FOR THE UPPER EXTREMITIES - THEORY AND CLINICAL-APPLICATION

Enhanced athletic performance emphasizes the muscle's ability to exert maximal force output in a minimal amount of time. Exaggerated maximal muscular force develops due to athletic movements producing a repeate d series of stretch-shortening cycles. The stretch-shortening cycle oc curs when elastic loading, through an eccentric muscular contraction, is followed by a burst of concentric muscular contraction. A form of e xercise called plyometrics employs a quick, powerful movement involvin g a prestretch of the muscle, followed by a shortening, concentric mus cular contraction, thus utilizing the stretch-shortening muscular cycl e. The literature contains numerous references to plyometric training for the lower extremity, but there is a lack of information on the upp er extremity plyometric program. Overhead activities, such as throwing , necessitate elastic loading to produce maximal, explosive, concentri c muscular contractions. Plyometric exercise employs the concept of th e stretch-shortening muscular cycle. The rehabilitation concept of spe cificity of training suggests plyometric exercise drills should be per formed by the throwing athlete. This paper discusses the basic neuroph ysiological science and theoretical basis for plyometric exercise, and it describes an upper extremity stretch-shortening exercise program f or the throwing athlete.