Cross-Body Versus Combined Sleeper Stretch for Posterior Shoulder Tightness: A Randomized Controlled Trial

TL;DR

This study compares two stretching methods for improving shoulder flexibility in young baseball players.

Contribution

The study provides evidence on the effectiveness of cross-body and combined sleeper stretches for posterior shoulder tightness.

Findings

Both stretching methods improved internal rotation and horizontal adduction range of motion.

Only the combined stretching method significantly improved total shoulder rotation.

No significant differences were found between the two groups in most outcomes.

Abstract

Background and objective

Posterior shoulder tightness (PST) is common in young overhead athletes and may increase the risk of shoulder injury. Cross-body and sleeper stretches are widely used, but their comparative effectiveness remains unclear. Hence, we conducted this study to address that gap in the literature

Methods

We performed a single-blind randomized controlled trial involving 24 adolescent baseball players (mean age 11.6 years); the participants were randomly assigned to a cross-body group (n = 12) or a combined group (cross-body plus sleeper, n = 12). Both groups performed daily stretching for three weeks. Shoulder range of motion (ROM) (internal rotation (IR), external rotation (ER), horizontal adduction (HA), and total rotation) was measured with a digital inclinometer before and after the intervention.

Results

Twenty-four participants completed the trial (combined: n = 12; single: n = 12). Both groups showed significant improvements in IR (combined: from 31.7° to 46.0°; single: from 26.9° to 42.0°) and HA ROM (combined: from 83.6° to 94.2°; single: from 82.9° to 91.9°). Total rotation improved significantly only in the combined group (from 104.6° to 123.9°), whereas ER did not change significantly in either group. No significant between-group differences were observed in any outcomes (p>0.05). No adverse events were reported. Post-hoc power analysis indicated that the study may have been underpowered to detect small between-group effects.

Conclusions

Cross-body stretching, performed alone or with sleeper stretching, is an effective approach for reducing PST in early adolescent baseball players. Level of evidence: 1b (individual randomized controlled trial).

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