strengthening is a common component of treatment. 3 In a side-lying hip abductor strength test, an adduction force is applied to the patient’s limb through a handheld dynamometer that either matches or exceeds the patient’s maximum isometric force. In a hip abductor eccentric strength test or “break test,” the
Richard A. Brindle, David Ebaugh and Clare E. Milner
Jerónimo Aragón-Vela, Yaira Barranco-Ruiz, Cristina Casals-Vázquez, Julio Plaza-Díaz, Rafael A. Casuso, Luis Fontana and Jesús F. Rodríguez Huertas
and performance of athletes’ lower body is half squat ( McMaster, Gill, Cronin, & McGuigan, 2014 ), both male and female athletes carried out a maximum incremental strength test (MIST) in a half-squat apparatus with increasing intensities until they reached their one repetition maximum (1RM). We show
Sally J. McLaine, Karen A. Ginn, Cecilia M. Kitic, James W. Fell and Marie-Louise Bird
Context: The reliable measurement of shoulder strength is important when assessing athletes involved in overhead activities. Swimmers' shoulders are subject to repetitive humeral elevation and consequently have a high risk of developing movement-control issues and pain. Shoulder-strength tests performed in positions of elevation assist with the detection of strength deficits that may affect injury and performance. The reliability of isometric strength tests performed in positions of humeral elevation without manual stabilization, which is a typical clinical scenario, has not been established. Objective: To establish the relative and absolute intrarater reliability of shoulder-strength tests functional to swimming in 3 body positions commonly used in the clinical setting. Design: Repeated-measures reliability study. Setting: Research laboratory. Subjects: 15 university students and staff (mean ± SD age 24 ± 8.2 y).Intervention: Isometric shoulder-strength tests were performed in positions of humeral elevation (flexion and extension in 140° abduction in the scapular plane, internal and external rotation in 90° abduction) on subjects without shoulder pain in supine, prone, and sitting. Subjects were tested by 1 examiner with a handheld dynamometer and retested after 48 h. Main Outcome Measures: Relative reliability (ICC3,1) values with 95% CI. Absolute reliability was reported by minimal detectable change (MDC). Results: Good to excellent intrarater reliability was found for all shoulder-strength tests (ICC .87-.99). Intrarater reliability was not affected by body position. MDC% was <16% for every test and ≤11% for tests performed in supine. Conclusions: Shoulder flexion, extension, and internal- and external-rotation strength tests performed in humeral elevation demonstrated excellent to good intrarater reliability regardless of body position. A strength change of more than 15% in any position can be considered meaningful.
Dale Bickham, Warren Young and Peter Blanch
To determine the relationship between lumbopelvic (LP) stabilization strength and pelvic motion during running.
Runners were assessed for pelvic motion and undertook an LP stabilization strength test.
Sixteen elite male middle- and long-distance runners.
Pelvis kinematics were assessed while subjects ran at 5 m/s on a treadmill.
Main Outcome Measures:
Angular pelvis displacement was divided into 3 axes of rotation: pelvic tilt, obliquity, and rotation. LP stabilization strength was the capacity to resist increasing static loads applied to each leg and maintain a neutral LP zone. Intercorrelations were calculated for all measures of pelvic motion and LP stabilization strength.
There were no significant relationships found among any of the variables (P > .05). However, the LP stabilization strength test possessed good interday reliability.
The relationship between pelvic motion and muscle function should be studied under a variety of other conditions.
Roald Otten, Johannes L. Tol, Per Holmich and Rodney Whiteley
Gluteus medius (GM) muscle dysfunction is associated with overuse injury. The GM is functionally composed of 3 separate subdivisions: anterior, middle, and posterior. Clinical assessment of the GM subdivisions is relevant to detect strength and activation deficits and guide specific rehabilitation programs. However, the optimal positions for assessing the strength and activation of these subdivisions are unknown.
The first aim was to establish which strength-testing positions produce the highest surface electromyography (sEMG) activation levels of the individual GM subdivisions. The second aim was to evaluate differences in sEMG activation levels between the tested and contralateral (stabilizing) leg.
Twenty healthy physically active male subjects participated in this study. Muscle activity using sEMG was recorded for the GM subdivisions in 8 different strength-testing positions and analyzed using repeated-measures analysis of variance.
Significant differences between testing positions for all 3 GM subdivisions were found. There were significant differences between the tested and the contralateral anterior and middle GM subdivisions (P < .01). The posterior GM subdivision showed no significant difference (P = .154).
Side-lying in neutral and side-lying with hip internal rotation are the 2 positions recommended to evaluate GM function and guide specific GM rehabilitation.
Ralf Roth, Lars Donath, Lukas Zahner and Oliver Faude
For performance and injury prevention in sport, core strength and endurance are focused prerequisites. Therefore we evaluated characteristics of trunk muscle activation and performance during strength-endurance related trunk field tests. Strength-endurance ability, as total time to failure, and activation of trunk muscles was measured in 39 football players of the highest German female football league (Bundesliga) (N = 18, age: 20.7 y [SD 4.4]) and the highest national male under-19 league (N = 21, age: 17.9 y [0.7]) in prone plank, side plank, and dorsal position. Maximal isometric force was assessed during trunk extension and flexion, rotation, and lateral flexion to normalize EMG and to compare with the results of strength-endurance tests. For all positions of endurance strength tests, a continuous increase in normalized EMG activation was observed (P < .001). Muscle activation of the rectus abdominis and external oblique in prone plank position exceeded the maximal voluntary isometric contraction activation, with a significantly higher activation in females (P = .02). We conclude, that in the applied strength-endurance testing, the activation of trunk muscles was high, especially in females. As high trunk muscle activation can infer fatigue, limb strength can limit performance in prone and side plank position, particularly during high trunk muscle activation.
David A. Krause, Mathew D. Neuger, Kimberly A. Lambert, Amanda E. Johnson, Heather A. DeVinny and John H. Hollman
Hip-muscle impairments are associated with a variety of lower-extremity dysfunctions. Accurate assessment in the clinical setting can be challenging due to the strength of hip muscles relative to examiner strength.
To examine the influence of examiner strength and technique on manual hip-strength testing using a handheld dynamometer.
30 active adults (age 24 ± 1.4 y).
Three examiners of different strength performed manual muscle tests (MMT) in 2 different positions for hip extension, abduction, and external rotation using a MicroFet handheld dynamometer. Examiner strength was quantified via a 1-repetition-maximum leg press and chest press with a Keiser A420 pneumatic resistance machine.
Main Outcome Measures:
Intrarater reliability (ICC3,1), interrater reliability (ICC2,1), and measured torque values.
Intrarater reliability for all measurements ranged from .82 to .97. Interrater reliability ranged from .81 to .98. Main effects for hip extension revealed a significant difference in torque values between examiners and between techniques. For the short-lever hip-abduction and seated hip-external-rotation tests, there was a significant difference between examiners. There was no significant difference in measured torque values between examiners with the long-lever hip-abduction or the prone hip-external-rotation tests.
MMT of the hip may be performed with high reliability by examiners of different strength. To obtain valid MMT measurements of hip muscles, examiners must consider their own strength and testing techniques employed. The authors recommend a long-lever technique for hip abduction and a prone position for testing hip external rotation to minimize the influence of examiner strength. Both positions appear to provide mechanical advantages to the examiner compared with the alternative techniques. The authors are unable to recommend a preferred hip-extension-testing technique to minimize the influence of examiner strength.
Megan Q. Beard, Samantha A. Boland and Phillip A. Gribble
, transportable, and more economical. Although the HHD can be effective, the reliability of the device can be influenced by examiner experience, patient position, and the use of stability straps. Previous studies have determined isometric strength testing using a HHD can have high interexaminer reliability and
Dusa Marn-Vukadinovic and Helena Jamnik
Valid patient-based outcome instruments are necessary for comprehensive patient care that focuses on all aspects of health, from impairments to participation restrictions.
To validate the Slovenian translation of Medical Outcome Survey (MOS) Short Form Health Survey (SF-36) and to assess relations among various knee measurements, activity tested with Oxford Knee Score (OKS) and health-related quality of life as estimated with SF-36 domains.
Descriptive validation study.
Isokinetic laboratory in outpatient rehabilitation unit.
101 subjects after unilateral sport knee injury.
All subjects completed the SF-36 and OKS, and isokinetic knee-muscle strength output at 60°/s was determined in 78 participants. Within a 3-d period, 43 subjects completed the SF-36 and OKS questionnaires again.
Main Outcome Measures:
Reliability testing included internal consistency and test–retest reliability. Correlations between SF-36 subscales and OKS were calculated to assess construct validity, and correlation between SF-36 subscales and muscle strength was calculated to assess concurrent validity.
Chronbach α was above .78 for all SF-36 subscales. ICCs ranged from .80 to .93. The correlation between OKS and the physical-functioning subscale, showing convergent construct validity, was higher (r = .83, P < .01) than between OKS and mental health (r = .50, P < .01), showing divergent construct validity. Knee-extensor weakness negatively correlated with physical-functioning (r = −.59, P < .01) and social-functioning (r = −.43, P < .01) subscales.
The Slovenian translation of the SF-36 is a reliable and valuable tool. The relationships between knee-muscle strength and activity and between knee-muscle strength and SF-36 subscales in patients after sport knee injury were established.
Alexander Törpel, Tim Becker, Angelina Thiers, Dennis Hamacher and Lutz Schega
Context:The use of isokinetic dynamometers playing an important role in different settings of sports and medicine. Therefore, a high reliability of these devices is required. Objective: The aim of this study was to examine the intersession reliability of the dynamometer BTE PrimusRS regarding to the isolated single-joint exercises extension/flexion of the knee and elbow for isokinetic testing. Design: Intersession reliability. Setting: Clinical settings and sports science. Participants: 16 young male students. Intervention: The testing protocol includes 5 consecutive repetitions (concentric/concentric) at a velocity of 60°/s for the exercises. Main Outcome Measures: Raw data of torque curves were used to determine the peak torque. Reliability was evaluated with the intraclass correlation coefficient (ICC), the limits of agreement (LoA), and the bias and the variability of measurements (V). Results: High ICC values (.954-.991) were found for the used exercises. However, the LoAs yielded up to over 16 Nm and the V yielded up to nearly 9 % in several testing exercises, indicating poor absolute reliability. Conclusion: The BTE PrimusRS shows good to excellent reliability. However, regarding the absolute measures of reliability, the users must decide as experts in their fields whether this reliability is sufficient for their purposes.