Affiliations: [a] Centre de Recherches en Activités Physiques et
Sportives (CRAPS UPRES EA2131), UFR Sciences et Techniques des Activités
Physiques et Sportives, Université de Caen Basse-Normandie, Caen,
France
Note: [] Address for correspondence: Antoine Gauthier, UFR STAPS Caen,
Université de Caen Basse-Normandie, 2 Boulevard du Maréchal Juin, 14032
Caen Cedex, France. Tel.: +33 2 31 56 72 63; E-mail:
Antoine.gauthier@unicaen.fr
Abstract: The purpose of this study was to explore the effects of intensive
tennis practice on the mechanical and electromyographic (EMG) activity of the
external (ER) and internal (IR) rotators of the shoulder. Isokinetic and EMG
testing of tennis (T, N=8) and control (C, N=8) subjects was performed using a CYBEX NORM. Shoulder
rotation strength was measured at 5 angular velocities: concentric 60, 180, 300
and eccentric 60 and 180°/s during which peak torque
(PT) and EMG activity of the infraspinatus (ER) and pectoralis major (IR) was
recorded. For the T group dominant side (DS) the ER/IR ratio was lower than the
non dominant side (NDS) whereas no such difference was observed between DS and
NDS of C group. No ERecc/IRcon ratio difference was observed between sides and
groups. ER co-activation in the T group was greater in the DS compared to the
NDS and the DS of C group, while values were the same for both sides of C
group. It therefore seems that tennis players present an adaptation to their
activity. However their mechanical and EMG values deviate quite sharply from
standard values which may potentially account for injury.
