The Effectiveness of an Exercise Program on Scapulohumeral Rhythm, Range of Motion, and Stability in Young Female Handball Players

Condition(s) studied

Investigational drug(s) / intervention(s)

Modified Watson-based scapular exercise program: An 8-week dominant-limb exercise program based on the Watson rehabilitation approach, incorporating scapular positioning correction, scapular-specific cueing, and progressive exercises performed with two elastic resistance bands.

Active Comparator: Standard upper-limb exercise program: An 8-week dominant-limb standardized upper-limb exercise program performed with one elastic resistance band and without scapular positioning correction or scapular-specific cueing.

Study summary

This record describes a planned randomized parallel-group trial of a modified Watson-based shoulder exercise program in female handball players. An internal pilot phase was conducted first to evaluate feasibility and obtain preliminary estimates to inform the definitive trial.

Eligibility

Primary outcome measure(s)

• Scapulohumeral rhythm — through study completion, an average of 2 years
  Scapular upward rotation is assessed with the Digital Inclinometer (BASELINE 12-1057) in a seated position to minimize compensatory movements of the trunk and lower extremities. The first measurement is taken at baseline (0° of shoulder flexion), followed by additional measurements at 30°, 60°, 90°, and 120° of shoulder flexion. Each position is held for 10-15 seconds to ensure stable measurement conditions. Measurements are repeated three times and the average is used for analysis. The assessment will be performed on both the dominant and non-dominant upper limb to evaluate movement symmetry. Data will be recorded manually by a research assistant to reduce the risk of reading errors and to ensure measurement accuracy. Statistical analysis will be performed to determine the scapulohumeral rhythm across different ranges of motion and to identify potential movement asymmetries.
• ISOMETRIC STRENGTH TEST - Internal and External Rotation — through study completion, an average of 2 years
  Isometric strength assessment of the shoulder girdle muscles will be conducted using the Lafayette Hand-Held Dynamometer (HHD). For the rotator muscles, measurements will be performed in the prone position with the shoulder abducted to 90° and the elbow flexed to 90°, with the forearm hanging freely over the edge of the examination table. This setup will be used for both internal and external rotation strength assessments. Results are expressed in Newtons (N) or normalized to body weight as Newtons per kilogram (N/kg).
• Y-Balance Upper Quarter Test (YBT-UQ) — through study completion, an average of 2 years
  The Y-Balance Upper Quarter Test (YBT-UQ) is used to assess upper extremity stability and reach performance. The test requires the participant to maintain a single-arm support position while the opposite arm performs reaching movements in three directions: anterior (forward), inferolateral (diagonally opposite the supporting hand), and superolateral (diagonally toward the supporting hand). Each reach is measured in centimeters, and the final score for each direction is calculated as the average of three trials. The test will be performed on both upper limbs and arm length will be included in the analysis to ensure standardized results. Results will be reported in centimeters, "cm", and Upper Limb Length % (standardized by upper limb length).

Trial sites (1)

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