Functional tests are widely used in the assessment of sports injuries to analyze aspects such as muscle strength, power, and athlete agility, being routinely applied in clinical practice for the prevention and rehabilitation of these injuries. The Upper Limb Rotation Test (ULRT) are frequently used for the evaluation of the upper limb functional status of athletes. However, the association between ULRT scores and isometric muscle strength of the kinetic chain muscles in swimmers is not completely understood.

To evaluate the correlation between the isometric muscle strength of the kinetic chain muscles and the ULRT in swimmers.

This is a cross-sectional study that includes swimmers of both sexes, aged between 12 and 60 years, with at least 1 year of competitive practice, and a minimum of two training sessions per week. This study was approved by Ethics Research Committee. The ULRT was performed with the swimmers in a modified flexion position (on their elbows), close to a wall. They performed trunk rotation and external shoulder rotation at 90° of abduction and external rotation, touching a tape on the wall as quickly as possible for 15 seconds. The athletes performed three trials, and the mean was considered for the analysis. The peak isometric muscle strength of the shoulder elevators (scaption), shoulder internal and external rotators, lower trapezius (LT), serratus anterior (SA), trunk extensors and flexors, hip abductors and rotators (HIPSIT), hip flexors (HF), and knee extensors (KE) were measured using a handheld isometric dynamometer. The association between ULRT and muscle strength was assessed with Pearson Correlation Coefficient, which was classified as weak (0–0.39), moderate (0.40–0.69), and strong (0.70–1.00). A significance level of p < 0.05 was adopted. The data were analyzed with SPSS software version 23.0.

A total of 50 athletes participated in the study, with mean age of 30.46 ± 14.27 and 27 (54%) were male. The ULRT showed a weak positive correlation with internal shoulder rotators (r = 0.36; p = 0.008) and moderate positive correlation with shoulder elevators (r = 0.40; p = 0.004), external shoulder rotators (r = 0.41; p = 0.002), LT (r = 0.43; p = 0.001), SA (r = 0.42; p = 0.002), trunk flexors (r = 0.57; p < 0.000), trunk extensors (r = 0.43; p = 0.001), HIPSIT (r = 0.44; p = 0.001), HF (r = 0.43; p < 0.000) and KE (r = 0.44; p = 0.001).

The study showed that performance in the ULRT is associated with muscle strength of shoulder elevators (scaption), external shoulder rotators, LT, SA, trunk extensors and flexors, HIPSIT, HF and KE. The results demonstrate that higher muscle strength in these muscles is associated with better performance in the test, highlighting the importance of the kinetic chain.

These findings can help clinicians to identify which components of the kinetic chain might affect ULRT performance.