Relationships among lateral medicine ball throw test performance, HIP and trunk muscle strength, and lower limb kinematics: A cross-sectional study.

INTRODUCTION: The lateral medicine ball throw (LMBT) test is used to evaluate the throwing action, involving the entire kinetic chain and the principle of force transfer, with association between the strength of the lower limb and trunk muscles and the lower limb kinematics. The LMBT to investigate the association between lower limb kinematics and hip and trunk muscle strength. EXPERIMENTAL: This was a cross-sectional study with 84 healthy and physically active young people. Determinations were made of the maximum isometric strengths of the hip abductor, lateral rotator, extensor, and flexor muscles, and the trunk lateral flexors and extensors. Kinematic analyses (2D) of the hip, knee, and ankle in the sagittal and frontal planes were performed during the countermovement phase of the LMBT, together with quantification of LMBT. Statistical analysis of the associations employed multiple linear regression, with α = 5%. RESULTS: There were significant associations between the LMBT and the independent variables hip extensors strength, trunk flexors strength, valgus angle, and knee flexion angle and gender. The regression model presented adjusted R2 = 0.622. CONCLUSIONS: LMBT was influenced by the trunk flexor and hip extensor muscle strengths, knee flexion kinematics, lower limb valgus in the countermovement phase, and gender.

Relationship between upper limb physical performance tests and muscle strength of scapular, shoulder and spine stabilizers: A cross-sectional study.

INTRODUCTION: Performance tests of the upper limb have been frequently used in the evaluation of individuals to identify risk of injury and to determine improvement in physical performance. Understanding the variables related to the performance of the tests is important for better applicability and interpretation of test results. The aim of this cross-sectional study was to investige the correlation between isometric strength of scapular, shoulder and spine muscles with physical performance test of upper limb in men and women. EXPERIMENTAL: Forty-nine healthy and physically conditioned individuals, men (n = 24) (22,7 ± 3,2 years; 74,6 ± 8,1 Kg; 176,7 ± 7,1 cm) women (n = 25) (23 ± 2,7 years; 61,5 ± 9,1 Kg; 163,2 ± 5,6 cm), were evaluated for shoulder abductor isometric strength (S-ABD); Middle (MT) and lower (LT) trapezium; lateral shoulder rotators (S-LR); flexors (T-FLEX), lateral incliners (T-INCL), and trunk extenders (T-EXT). Evaluation of upper limb physical performance was carried out by Upper Quarter Y Balance test (YBT-UQ) and Chain upper extremity stability test (CKC-UEST). Pearson's test (r values) p ≤ 0.05 was used to analyze the correlation. RESULTS: The results reveal strong correlations between S-ABD and CKC-UEST in male group; and strong correlations in female group between S-ABD strength with CKC-UEST; and S-LR with all YBT-UQ directions and score and between T-EXT strength with CKC-UEST. CONCLUSION: Therefore, strength of shoulder and spine stabilizers influences performance in upper limb tests, but with different correlations as to sex. To improve test performance, it may be important to increase the strength of the shoulder and spine muscles.