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Background: Systematizing reliable protocols and procedures for strength assessment in handball has allowed for a more thorough kinetic analysis and increased precision in detecting training-induced changes in muscular strength. The evaluation of upper limb strength with a bilateral standing press (BSP) exercise in handball players approximates blocking actions in the defensive phase, pushing and fixation., Aim: The aim of this study was to analyze the relative and absolute reliability of intra-session comparisons in an isometric peak muscle strength protocol in a bilateral standing press (BSP) exercise among female handball players., Methods: Sixteen young female handball players at an international level, aged between 22 ± 4 years, with no prior experience in using functional electromechanical dynamometers (FEMD) participated in this study. The participants initiated the assessment of maximum isometric force in a bipedal stance with a forward projection of the dominant foot between 20 and 30 cm. The knees were kept semi-flexed, and the hip extension of the non-dominant limb ranged from 15 to 20°. Bilateral anterior push of the upper limb was performed with shoulder abduction and elbow flexion at 90°, maintaining a pronated hand position. Participants were instructed to exert three sets of maximal force for 5 s in BSP exercise. Relative reliability was assessed using the model intraclass correlation (ICC) and absolute reliability was assessed using the coefficient of variation (CV) and standard error of measurement (SEM). For this study, the parameters of maximum and mean muscle strength were considered., Results: The results demonstrated high relative reliability (ICC 0.93-0.97) and absolute reliability (SEM 0.19-2.79) y (CV 4.78-9.03) for both mean force and peak force, with no significant differences between the sets ( p > 0.05), indicating a negligible effect size (0.01-0.12)., Conclusion: The mean and peak isometric muscle strength for the BSP exercise controlled with FEMD in female handball players exhibits high relative and absolute reliability between series., Competing Interests: The authors declare that they have no competing interests., (© 2024 Cifuentes-Zapata et al.)

Background: The evaluation of the force in internal rotation (IR) and external rotation (ER) of the shoulder is commonly used to diagnose possible pathologies or disorders in the glenohumeral joint and to assess patient's status and progression over time. Currently, there is new technology of multiple joint isokinetic dynamometry that allows to evaluate the strength in the human being. The main purpose of this study was to determine the absolute and relative reliability of concentric and eccentric internal and external shoulder rotators with a functional electromechanical dynamometer (FEMD)., Methods: Thirty-two male individuals (21.46 ±  2.1 years) were examined of concentric and eccentric strength of shoulder internal and external rotation with a FEMD at velocities of 0.3 m s -1 and 0.6 m s -1 . Relative reliability was determined by intraclass correlation coefficients (ICC). Absolute reliability was quantified by standard error of measurement (SEM) and coefficient of variation (CV). Systematic differences across velocities testing circumstances, were analyzed with dependent t tests or repeated-measures analysis of variance in case of 2 or more than 2 conditions, respectively., Results: Reliability was high to excellent for IR and ER on concentric and eccentric strength measurements, regardless of velocity used (ICC: 0.81-0.98, CV: 5.12-8.27% SEM: 4.06-15.04N). Concentric outcomes were more reliable than eccentric due to the possible familiarization of the population with the different stimuli., Conclusion: All procedures examined showed high to excellent reliability for clinical use. However, a velocity of 0.60 m s -1 should be recommended for asymptomatic male patients because it demands less time for evaluation and patients find it more comfortable., Competing Interests: The authors declare there are no competing interests., (©2020 Martinez-Garcia et al.)

Aim: To determine the absolute and relative reliability of functional trunk tests, using a functional electromechanical dynamometer to evaluate the isokinetic strength of trunk flexors and to determine the most reliable assessment condition, in order to compare the absolute and relative reliability of mean force and peak force of trunk flexors and to determine which isokinetic condition of evaluation is best related to the maximum isometric., Methods: Test-retest of thirty-seven physically active male student volunteers who performed the different protocols, isometric contraction and the combination of three velocities (V 1 = 015 m s -1 , V 2 = 0.30 m  s -1 , V 3 = 0.45 m s -1 ) and two range of movement (R 1 = 25% cm ; R 2 = 50% cm) protocols., Results: All protocols to evaluate trunk flexors showed an absolute reliability provided a stable repeatability for isometric and dynamic protocols with a coefficient of variation (CV) being below 10% and a high or very high relative reliability (0.69 < intraclass correlation coefficient [ICC] > 0.86). The more reliable strength manifestation (CV = 6.82%) to evaluate the concentric contraction of trunk flexors was mean force, with 0.15 m  s -1 and short range of movement (V 1 R 1 ) condition. The most reliable strength manifestation to evaluate the eccentric contraction of trunk flexors was peak force, with 0.15 m  s -1 and a large range of movement (V 1 R 2; CV = 5.07%), and the most reliable way to evaluate isometric trunk flexors was by peak force (CV = 7.72%). The mean force of eccentric trunk flexor strength with 0.45 m  s -1 and short range of movement (V 3 R 1 ) condition (r = 0.73) was best related to the maximum isometric contraction., Conclusion: Functional electromechanical dynamometry is a reliable evaluation system for assessment of trunk flexor strength., Competing Interests: The authors declare there are no competing interests., (©2019 Rodriguez-Perea et al.)

Background: The aim of this study was to examine whether the addition of very light loads for modeling the force-velocity (F-V) relationship during the bench press (BP) exercise can confirm its experimental linearity as well as to increase the reliability and concurrent validity of the F-V relationship parameters (maximum force ( F 0 ), maximum velocity ( V 0 ), F-V slope, and maximum power ( P max ))., Method: The F-V relationship of 19 healthy men were determined using three different methods: (I) 6-loads free method: six loads performed during the traditional free-weight BP exercise (≈ 1-8-29-39-49-59 kg), (II) 4-loads free method: four loads performed during the traditional free-weight BP exercise (≈ 29-39-49-59 kg), and (III) 4-loads Smith method: four loads performed during the ballistic bench press throw exercise in a Smith machine (≈ 29-39-49-59 kg)., Results: The linearity of the F-V relationship was very high and comparable for the three F-V methods ( p = 0.204; median Pearson's correlation coefficient ( r ) = 0.99). The three methods were ranked from the most to the least reliable as follows: 6-loads free (coefficient of variation (CV) range = 3.6-6.7%) > 4-loads Smith (CV range = 4.6-12.4%) > 4-loads free (CV range = 3.8-14.5%). The higher reliability of the 6-loads free method was especially pronounced for F-V slope (CV ratio ≥ 1.85) and V 0 (CV ratio ≥ 1.49) parameters, while the lowest difference in reliability was observed for F 0 (CV ratio ≤ 1.27). The 6-loads free and 4-loads free methods showed a very high concurrent validity respect to the 4-loads Smith method for F 0 and P max ( r ≥ 0.89), a moderate validity for the F-V slope ( r = 0.66-0.82), and a low validity for V 0 ( r ≤ 0.37)., Discussion: The routine testing of the F-V relationship of upper-body muscles through the BP exercise should include trials with very light loading conditions to enhance the reliability of the F-V relationship., Competing Interests: The authors declare that they have no competing interests.