The influence of muscular strain on the proprioceptive capabil­ity of the shoulder joint.

Fromme A, Thorwesten L, Reer R, Lüttge JH, Jerosch J

Abstract

The aim ofthis study was to determine the influence of a previous muscular strain with medium lactate levels on the proprioceptive capability ofthe shoulder joint by means of an angle reproduction test in which the test persons have to reproduce given angles in different planes of motion. The tests were carried out on 26 wa­terpolo players (age: 16.9 ± 0.9 years, height: 183.8 ± 6.0 cm, weight: 76.5 ± 7.5 kg), who were members of the junior national team. Each player performed two angle reproduction tests of the shoulder joint in abduction, flexion, and rotation prior to and after a local exhaustive isokinetic muscular exercise of the shoulder and knee joint. The positions of the arms were indicated by reflecting skin markers and measured by an optical system for motion analysis. During rest the athletes achieved better scores in the angle reproduction test with than without visual control. Regard­ing rotation these differences were significant (p<0.05) for all given angles. There were no significant differences between dom­inant and non-dominant arm. After isokinetic exercise the lactate levels reached an average of 7.40 ± l.46 mmol/1. The angle repro­duction capability revealed a tendency to improvement for almost all angles, significance level, however, was achieved only for single angles. Our results suggest that muscular activity which leads to a medium increase of blood lactate improves the propri­oceptive capability. As possible reasons for this finding a better sensitivity of the receptors by warming up of the musculature as weil as an increased central nervous activity can be assumed.