Competitive Swimmers versus Sedentary People: A Predictive Model Based upon Normal Shoulder's Flexibility
Résumé
In swimming, the shoulder is subjected to multiple factors leading to a high injury rate, such as instability. This instability is related to an excessive shoulder laxity and could be an important basis for a variety of disorders of the anterior shoulder. This study intends to discriminate competitive swimmers and sedentary people using several shoulder measurements through logistic regression modelling, in order to propose a simple test to evaluate a shoulder joint's flexibility. Two samples (sedentary vs. swimmer) of 30 volunteers, presenting neither anterior shoulder pains nor pathologies, have been measured on their right and left sides of the shoulder joint using a mechanical goniometer. The testing session included 10 passive joint motions and 1 active test. The flexion measurement perfectly defines the complex flexibility of the shoulder from a discrimination/predictive viewpoint. The resulting model combines the right and left measurements of flexion into a meaningful pair of derived variables: a symmetric one and an asymmetric one. This study found that a competitive swimmer is characterised by his higher flexion value and his laterality.