Range of motion (ROM) and isometric strength of a Throwing Shoulder and their changes under training and playing season in Handball sport athletes Part I: Changes under pre-seasonal training
Abstract
The rotational capacity of the throwing shoulder and their changes during the pre-season and season in semi- and professional team handball athletes is not very much investigated yet. There are no data on changes in isometric strength as well, but correlations between the overhead- and throwing athlete shoulder, their changes in the rotational capacity and a risk of structural joint damages and symptoms.
Materials and Methods
In a longitudinal intra-individual investigation 27 semi- and professional male, third league team handball athletes underwent a specific clinical shoulder examination and were examined at the beginning (MZP 1) and end (MZP 2) of the pre-seasonal training (VP) at the dominant (throwing) and non dominant (non throwing) shoulder according to rotational strength (isometric) and range of motion.
Results
The internal rotation (IR) at the dominant throwing shoulder (WA) was significantly reduced in comparison to the non throwing shoulder (NWA) at both days of determinations (baseline, after 6 weeks). The external rotation (ER) at the WA was significantly greater than the ER at the NWA at both times. The total range of motion (tROM) and the GIRD was slightly, but not significantly reduced at the WA at the end of the VP. The external rotational gain (ERG) was significantly reduced during the VP. The isometric strength in IR and ER at the WA was larger in comparison to the NWA at baseline. During the VP a significant reduction in internal rotational (IR) and isometric strength was seen at the WA. The external rotational isometric strength (ER) significantly reduced as well over the period of time at the WA.
Conclusions
Over the period of 6 weeks the pre-seasonal training in team handball did not lead to significant pathological changes of the rotational capacities in shoulder joints, even not in a glenohumeral internal rotation deficit. The external rotation gain did significantly reduce after the period of the pre-seasonal training. The isometric strength in internal and external rotational movement also decreased significantly. Our data more likely show adaptive processes at the throwing shoulder joint according to the workload during training.