Shoulder Strength and Upper Body Field Performance Tests in Young Female Handball and Volleyball Athletes: Are There Differences Between Sports?

CONTEXT: Volleyball and handball players have usually been studied collectively as "overhead athletes," since throwing present similarities in the proximal to distal movement sequencing and upper limb joints ranges of motion. However, each sport presents specificities in the objectives when accelerating the ball and a variety of possible throwing techniques. Therefore, it is expected there may be differences in the shoulder and upper body physical performance between sports. OBJECTIVE: The aim of this study was to determine if there are differences in shoulder muscle strength and upper body field performance tests between volleyball and handball athletes. DESIGN: Cross-sectional. METHODS: Ninety-nine volleyball and handball female athletes aged between 13 and 20 years were evaluated for isometric shoulder abductor and rotator strength (handheld dynamometer) and upper body field performance tests: Y Balance Test-Upper Quarter, modified Closed Kinetic Chain Upper-Extremity Stability Test, and unilateral and bilateral Seated Medicine Ball Throw. RESULTS: Handball athletes presented greater shoulder internal rotation strength (between-group difference: 2.84; effect size 0.70), higher medial (between-group difference: 9.54; effect size 0.90), superolateral (between-group differences: 8.9; effect size 0.68), and composite scores (between-group difference 5.7; effect size 0.75) of the Y Balance Test-Upper Quarter and higher unilateral (between-group difference: 41.92; effect size 0.91) and bilateral (between-group difference: 46.11; effect size 0.83) Seated Medicine Ball Throw performance. Groups were not different for Closed Kinetic Chain Upper-Extremity Stability Test, external rotation, and abduction isometric strength. CONCLUSION: Our findings suggest that young female handball athletes present greater internal rotator strength and better performance in Y Balance Test-Upper Quarter and Seated Medicine Ball Throw compared to volleyball players. These differences may be related to the different demands required in the throwing movements performed in each sport and should be considered when assessing these populations.

Low back pain leads to a protective action of pain on dynamic postural stability.

Low back pain (LBP) is a painful manifestation in the lower part of the spine which causes disabilities changing the sensitivity of sensory neurons resulting in weakness of postural muscles interfering with the balance. It is not already clear if LBP people's muscle changes affect the centre of pressure (CoP) recovery in challenging stance perturbations. The aim of this study was to identify differences in the muscle reactions of people with and without LBP to control CoP in challenging stance perturbations. We applied low (Vel1) and high (Vel2) magnitude stance perturbation by a movable platform and evaluated (a) the magnitude and latency time of trunk and lower limb muscle activation, (b) and the displacement and the latency time of the first CoP peak. The latency of trunk and hip muscle activation on Vel2 was lower for LBP group. The CoP latency and displacement did not change between groups and velocities indicating that the muscles took the same time to overcome the external forces. In conclusion, the maintenance of CoP latency at both velocities was not affected on Vel2, suggesting that such alterations have protective action and preservation of the pain on the LPB group in challenging stance perturbations.