Affiliations: [a] Department of Clinical and Exercise Physiology,
University Hospital Saint-Étienne, Saint-Étienne, France | [b] Department of Physical Medicine and Rehabilitation,
University Hospital Saint-Étienne, Saint-Étienne, France | [c] Laboratory of Physiology and Exercise, LPE EA 4338,
Jean Monnet University, Saint-Étienne, France | [d] Medical Commission, French Athletics Federation (FFA),
Paris, France | [e] Institute of Formation in Physical Therapy, Saint
Michel, Saint-Étienne, France | [f] Institute of Sport Sciences, Department of Physiology,
Faculty of Biology and Medicine, University of Lausanne, Lausanne,
Switzerland
Note: [] Address for correspondence: Pascal Edouard, MD, PhD, Department
of Clinical and Exercise Physiology, LPE EA 4338, Bellevue Hospital, University
Hospital of Saint-Etienne, 42 055 Saint-Etienne cedex 2, France. Tel.: +33 674
574 691; E-mail: Pascal.Edouard42@gmail.com
Abstract: BACKGROUND: Adaptations to Internal (IR) and external (ER) rotator
shoulder muscles improving overhead throwing kinematics could lead to muscular
strength imbalances and be considered an intrinsic risk factor for shoulder
injury, as well as modified shoulder range of motion (RoM). OBJECTIVE: To establish profiles of internal and external rotation RoM and isokinetic IR and
ER strength in adolescent- and national-level javelin throwers. METHODS: Fourteen healthy subjects were included in this preliminary cross-sectional
study, 7 javelin throwers (JTG) and 7 nonathletes (CG). Passive internal and
external rotation RoM were measured at 90° of shoulder abduction.
Isokinetic strength of dominant and non-dominant IR and ER was evaluated during
concentric (60, 120 and 240°/s) and eccentric (60°/s)
contractions by Con-Trex® dynamometer
with the subject in a seated position with 45° of shoulder abduction in
the scapular plane. RESULTS: We reported significantly lower internal
rotation and significantly higher external rotation RoM in JTG than in CG.
Concentric and eccentric IR and ER strength were significantly higher for the
dominant shoulder side in JTG (P < 0.05), without significant differences
in ER/IR ratios. CONCLUSIONS: The main finding of this preliminary study
confirmed static and dynamic shoulder stabilizer adaptations due to javelin
throw practice in a population of adolescent- and national-level javelin throwers.
Keywords: Sports injury prevention, rotator cuff strength, isokinetic, range of motion, overhead sports, strength imbalance
