Reliability and validity of new isokinetic strength assessment for rotator cuff muscles in a muscle architecture-based position.

Background/aim: Isokinetic strength assessment of the rotator cuff muscle is frequently applied in a variety of shoulder postures, but none of these consider muscular architecture, which is one of the most important aspects of improving strength development. This study aimed to examine the test and retest reliability and validity of the muscle architecture-based position (MABP), which is 25° abduction and 20° external rotation, in healthy subjects to be able to select a better isokinetic assessment position for shoulder rotator cuff muscles. Materials and methods: A total of 54 healthy males with a mean age of 21.0 ± 1.2 years and mean body mass index of 22.8 ± 1.7 kg/m2 completed an isokinetic measurement session. All of the tests were performed on an IsoMed 2000 isokinetic dynamometer concentrically and eccentrically for both upper limbs at 60°/s angular velocity. All of the participants completed 3 measurement sessions: the first represented the isokinetic testing and was performed in the scapular neutral position (SNP) (45° shoulder flexion and abduction), the second represented the MABP (25° abduction and 20° ER) for shoulder rotator cuff muscles, and the third represented the test and retest of the MABP. Results: The correlations between the 2 techniques for assessing concurrent validity ranged from 0.908 to 0.994. The values obtained from the MABP were higher than those obtained in the SNP. There was no systematic bias for any measurements between the MABP and the retest of the MABP (p > 0.05). The intraclass correlation coefficients representing the test and retest reliability results for each variable measured with the MABP was higher than 0.98 and this value was considered as excellent reliability. Conclusion: In conclusion, the MABP can be used to assess the isokinetic strength of the rotator cuff muscles safely and confidently, with increased quantities of force being released and measurement at optimal muscle tension.

The Relationship Between Athletic Performance and Physiological Characteristics in Wheelchair Basketball Athletes.

Purpose: This study was aimed to investigate the relationship between athletic performance and physiological characteristics in wheelchair basketball (WB) athletes with different classification scores. Methods: Twenty-six (24 male and 2 female) WB athletes were involved into the study. The participants were divided into two functional categories (Category A:1.0-2.5 points, category B: 3.0-4.5 points) according to the IWBF rules. Shoulder internal (IR) and external rotation (ER) muscle strengths were evaluated with the ISOMED 2000® isokinetic dynamometer. Handgrip strength was evaluated with hydraulic hand dynamometer. Custom ramp protocol on treadmill was employed to measure aerobic capacity. Anaerobic capacity was evaluated with Wingate anaerobic power test in standard laboratory conditions. The athletic performance was assessed by 20 m Sprint test, Slalom Test, and Zone Shot tests. Results: Category B athletes achieved significantly better results in the measurements of shoulder IR and ER muscle strength, aerobic and anaerobic capacity, and athletic performance while the grip strength was found similar in the categories. There was a significant correlation between the athletic performance and shoulder IR and ER muscle strength, and aerobic and anaerobic capacities in two categories. There was no significant relationship between grip strength and athletic performance parameters in two categories. Conclusion: It was concluded that athletic performance in WB athletes with different classification scores is related to upper extremity muscle strength, aerobic, and anaerobic capacity. Additionally, upper limb muscle strength, athletic performance, aerobic and anaerobic capacity assessments to be made will contribute positively to the planning of individual training and exercise programs.