Effect of 6-week Shoulder Strengthening Exercises on Scapular Muscle Strength, Scapular Dyskinesis and Swim Performance in Asymptomatic Swimmers with Scapular Dyskinesis: A Quasi Experimental Study.

Scapular dyskinesis, is common among competitive swimmers due to repetitive overhead movements, leading to impaired performance and increased injury risk. Strengthening of the scapular stabilizing muscles plays a crucial role in improving shoulder function and enhancing stroke efficiency in swimmers. The study aims to evaluate the effect of a 6-week shoulder strengthening program on scapular muscle strength, scapular dyskinesis, and swimming performance in competitive swimmers aged 12–18 years. Swimmers with scapular dyskinesis will be recruited through screening using the Scapular Dyskinesis Test and confirmed with the Lateral Scapular Slide Test.

Inclusion Criteria: Competitive swimmers aged 12–18 years, males and females, identified with scapular dyskinesis.

Exclusion Criteria: Swimmers with upper quadrant musculoskeletal injuries, neurological or cardiopulmonary conditions, those participating in multiple sports (e.g., water polo, triathlon), or those not completing at least 15/18 sessions.

Baseline assessments will include:

1. Muscle strength using a Push–Pull Dynamometer for shoulder internal rotators and external rotators, serratus anterior, lower trapezius, middle trapezius, and rhomboids

2. 1RM testing for shoulder internal rotators and external rotators, serratus anterior, lower trapezius, middle trapezius, and rhomboids for evaluating the baseline strength to begin with the training.

3. Stroke efficiency calculated by Stroke Index.

Methodology-

The test will be initiated with the Scapular Dyskinesis Test, and positive subjects will be further tested with the Lateral Scapular Slide Test. Strength of middle and lower trapezius, serratus anterior, rhomboids, shoulder internal and external rotators will be assessed with a push-pull dynamometer. One-repetition maximum for all exercise prescribed. RM) will be determined

Pre-stretching elastic bands to 50-100 times of standardized will stabilize mechanical properties and use the same set of elastic bands for all tests. Resistance testing begins with the yellow band and increases incrementally, with a one-minute rest after each level and a 3-second isometric hold as the ending position. Failure was determined as inability to complete or maintain movement, with a repeat trial allowed after rest. Verbal cues and visual feedback will be given continuously for orderly movement patterns. Standardized 1RM testing protocols will be performed for internal rotation, external rotation, serratus anterior, lower trapezius, middle trapezius, and rhomboids by using resistance bands in standardized positions. All pre-test measurements will be taken prior to intervention.

After baseline measurements, the participants will then attend a six-week shoulder strengthening regimen, with every session followed by a 5-10-minute dynamic stretching and mobility warm-up. volume load for training will start at one level below each participant’s 1RM for each muscle group, using the appropriate colour-coded band, and will be progressively overloaded every two weeks following the band colour hierarchy (yellow, red, green, blue, black, silver, gold). Volume load will also be increased across the training period, starting with 2 sets of 8 repetitions during weeks 1–2, progressing to 3 sets of 10 repetitions in weeks 3–4, and 4 sets of 12 repetitions in weeks 5–6.

Post-intervention the outcomes will be reassessed to determine changes in scapular muscle strength, scapular control, and swim stroke efficiency.