Validity of the Open Barbell and Tendo Weightlifting Analyzer Systems Versus the Optotrak Certus 3D Motion-Capture System for Barbell Velocity

2019 ◽  
Vol 14 (4) ◽  
pp. 540-543 ◽  
Author(s):  
Jacob A. Goldsmith ◽  
Cameron Trepeck ◽  
Jessica L. Halle ◽  
Kristin M. Mendez ◽  
Alex Klemp ◽  
...  
Keyword(s):  
Motion Capture ◽  
Analysis Of Variance ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Motion Capture System ◽  
Training Experience ◽  
Warm Up ◽  
3 Dimensional ◽  
Intraclass Correlation Coefficients ◽  
3D Motion Capture

Purpose: To examine the validity of 2 linear position transducers, the Tendo Weightlifting Analyzer System (TWAS) and Open Barbell System (OBS), compared with a criterion device, the Optotrak Certus 3-dimensional motion-capture system (OC3D). Methods: A total of 25 men (age, 25 [3] y; height, 174.0 [6.7] cm; body mass, 89.0 [14.7] kg; squat 1-repetition maximum [1RM], 175.8 [34.7] kg) with ≥2 y of resistance-training experience completed a back 1RM and 1 set to failure at 70% of 1RM. Average concentric velocity (ACV) and peak concentric velocity (PCV) were recorded by all 3 devices during the final warm-up set, all 1RM attempts, and every repetition during the 70% set. Results: In total, 575 samples were obtained. Bland–Altman plots, mountain plots, a 1-way analysis of variance, SEM, and intraclass correlation coefficients were used to analyze validity. The analysis of variance showed no difference (P = .089) between devices for ACV. However, for PCV, TWAS was significantly different (ie, inaccurate) from OC3D (P < .001) and OBS (P = .001), but OBS was similar (P = .412) to OC3D. For ACV, intraclass correlation coefficients were higher for OBS than for TWAS. Bland–Altman plots showed agreement for ACV for both devices against OC3D but large limits of agreement for PCV for both devices. Mountain plots showed valid ACV for both devices, however, but slightly greater ACV and PCV accuracy with OBS than TWAS. Conclusions: Both devices may provide valid ACV measurements, but some metrics suggest more accurate ACV with OBS vs TWAS. For PCV, neither device is particularly accurate; however, OBS seems to be more accurate than TWAS.

scholarly journals Is there a relationship between the overhead press and split jerk maximum performance? Influence of sex

2021 ◽  
pp. 174795412110204
Author(s):  
Marcos A Soriano ◽  
G Gregory Haff ◽  
Paul Comfort ◽  
Francisco J Amaro-Gahete ◽  
Antonio Torres-González ◽  
...  
Keyword(s):  
Confidence Intervals ◽  
Body Mass ◽  
Upper Limb ◽  
High Reliability ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Training Experience ◽  
Maximum Performance ◽  
Repetition Maximum ◽  
Intraclass Correlation Coefficients

The aims of this study were to (I) determine the differences and relationship between the overhead press and split jerk performance in athletes involved in weightlifting training, and (II) explore the magnitude of these differences in one-repetition maximum (1RM) performances between sexes. Sixty-one men (age: 30.4 ± 6.7 years; height: 1.8 ± 0.5 m; body mass 82.5 ± 8.5 kg; weightlifting training experience: 3.7 ± 3.5 yrs) and 21 women (age: 29.5 ± 5.2 yrs; height: 1.7 ± 0.5 m; body mass: 62.6 ± 5.7 kg; weightlifting training experience: 3.0 ± 1.5 yrs) participated. The 1RM performance of the overhead press and split jerk were assessed for all participants, with the overhead press assessed on two occasions to determine between-session reliability. The intraclass correlation coefficients (ICC) and 95% confidence intervals showed a high reliability for the overhead press ICC = 0.98 (0.97 – 0.99). A very strong correlation and significant differences were found between the overhead press and split jerk 1RM performances for all participants (r = 0.90 [0.93 – 0.85], 60.2 ± 18.3 kg, 95.7 ± 29.3 kg, p ≤ 0.001). Men demonstrated stronger correlations between the overhead press and split jerk 1RM performances (r = 0.83 [0.73-0.90], p ≤ 0.001) compared with women (r = 0.56 [0.17-0.80], p = 0.008). These results provide evidence that 1RM performance of the overhead press and split jerk performance are highly related, highlighting the importance of upper-limb strength in the split jerk maximum performance.

scholarly journals Interday Reliability and Usefulness of a Reactive Strength Index Derived From 2 Maximal Rebound Jump Tests

2019 ◽  
Vol 14 (9) ◽  
pp. 1200-1204
Author(s):  
Thomas M. Comyns ◽  
Eamonn P. Flanagan ◽  
Sean Fleming ◽  
Evan Fitzgerald ◽  
Damian J. Harper
Keyword(s):  
Female Athletes ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Strength Index ◽  
Warm Up ◽  
Intraclass Correlation Coefficients ◽  
Jump Test ◽  
Moderate Change ◽  
Familiarization Session

Purpose: To examine the interday reliability and usefulness of a reactive strength index (RSI) derived from a maximal 5-rebound jump test (5max RJT) and a maximal 10-rebound jump test (10/5 RJT). Methods: Twenty male field-sport athletes (24.5 [3.0] y, 1.78 [0.1] m, 84.9 [5.2] kg) and 15 female participants (21.1 [0.9] y, 1.65 [0.73] m, 62.0 [5.1] kg) performed 2 maximal repetitions of the 5max RJT and the 10/5 RJT on 2 testing days after a specific warm-up. A 1-wk period separated testing days, and these sessions were preceded by a familiarization session. RSI was calculated by dividing jump height (in meters) by contact time (in seconds). The 5max RJT and the 10/5 RJT trial with the highest RSI on each testing day were used for reliability and usefulness analysis. Results: Both tests were deemed reliable for determining RSI for male, female, and pooled male and female cohorts, as the intraclass correlation coefficients were ≥.80 and the coefficient of variation was ≤10%. Only the 5max RJT was rated as “good” at detecting the smallest worthwhile change in performance for female athletes (smallest worthwhile change: 0.10 > typical error: 0.07). The 5max RJT for men and the 10/5 RJT for men and women were rated “good” in detecting a moderate change in performance only. Conclusions: Both tests are reliable for the determination of RSI, but the usefulness of the tests in detecting the smallest worthwhile change is questionable.

scholarly journals Influence of Radiographic Viewing Perspective on Glenoid Inclination Measurement

2019 ◽  
Vol 3 ◽  
pp. 247154921882498 ◽  
Author(s):  
Peter N Chalmers ◽  
Thomas Suter ◽  
Matthijs Jacxsens ◽  
Yue Zhang ◽  
Chong Zhang ◽  
...  
Keyword(s):  
Gold Standard ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Two Dimensional ◽  
Viewing Angle ◽  
Plain Radiographs ◽  
3 Dimensional ◽  
Intraclass Correlation Coefficients ◽  
Orthopedic Surgeons ◽  
Viewing Perspective

Introduction The purposes of this study were to determine (1) whether glenoid inclination (GI) could be accurately measured on plain radiographs as compared to a gold-standard 3-dimensional (3D) measure and (2) whether GI could be reliably measured on plain radiographs. Materials and Methods Digitally reconstructed radiographs (DRRs) were made from 3D computed tomography reconstructions of 68 normal cadaver scapulae. DRRs were made in a variety of viewing angles. Inclination was measured on these DRRs. These measurements were also made using a gold-standard 3D method. Measurements were made by 2 orthopedic surgeons and 1 surgeon twice, to calculate interrater and intrarater intraclass correlation coefficients (ICCs). Results The gold-standard 3D β was 83 ± 5° (72°–98°). On neutral plain radiographs, the mean ± standard deviation 2D β angle was 80 ± 6° (range, 66°–99°). With regard to accuracy, the 2D β angle was significantly different from the 3D β angle, with the 2D β underestimating the 3D β by 5° (95% confidence intervals −1 to 12). With regard to reliability, interrater ICCs for 2D β with a neutral viewing angle was 0.79. Two-dimensional β varied widely with viewing angle from 0.24 to 0.88. Interrater ICCs for the 3D method was 0.83 (0.60–0.92). Intrarater ICCs for all 3 techniques were high (>0.91). Conclusions Two-dimensional radiographic GI measurement is not accurate, as it underestimates the 3D value by an average of 5° when compared to the gold-standard 3D measurement. GI 2D measurement reliability varies with viewing angle on plain radiographs and thus to accurately and reliably measure inclination 3D imaging is necessary.

scholarly journals Kinematics or Kinetics: Optimum Measurement of the Vertical Variations of the Center of Mass during Gait Initiation

Sensors ◽  
2021 ◽  
Vol 21 (23) ◽  
pp. 7954
Author(s):  
Antoine Langeard ◽  
Charlotte Mathon ◽  
Mourad Ould-Slimane ◽  
Leslie Decker ◽  
Nicolas Bessot ◽  
...  
Keyword(s):  
Motion Capture ◽  
Center Of Mass ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Minimal Detectable Change ◽  
Intraclass Correlation Coefficients ◽  
Kinematic Method ◽  
Risk Of Falls ◽  
Vertical Variations

Background: During gait, the braking index represents postural control, and consequently, the risk of falls. Previous studies based their determination of the braking index during the first step on kinetic methods using force platforms, which are highly variable. This study aimed to investigate whether determining the braking index with a kinematic method, through 3D motion capture, provides more precise results. Methods: Fifty participants (20 to 40 years) performed ten trials in natural and fast gait conditions. Their braking index was estimated from their first step simultaneously using a force platform and VICON motion capture system. The reliability of each braking index acquisition method was assessed by intraclass correlation coefficients, standard error measurements, and the minimal detectable change. Results: Both kinetic and kinematic methods allowed good to excellent reliability and similar minimum detectable changes (10%). Conclusion: Estimating the braking index through a kinetic or a kinematic method was highly reliable.

scholarly journals Association Between Markerless Motion Capture Screenings and Musculoskeletal Injury Risk for Military Trainees: A Large Cohort and Reliability Study

2021 ◽  
Vol 9 (10) ◽  
pp. 232596712110416
Author(s):  
Ben R. Hando ◽  
W. Casan Scott ◽  
Jacob F. Bryant ◽  
Juste N. Tchandja ◽  
Ryan M. Scott ◽  
...  
Keyword(s):  
Lower Extremity ◽  
Motion Capture ◽  
Injury Risk ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Musculoskeletal Injury ◽  
Retest Reliability ◽  
Intraclass Correlation Coefficients ◽  
Markerless Motion Capture ◽  
Test Retest Reliability

Background: Markerless motion capture (MMC) systems used to screen for musculoskeletal injury (MSKI) risk have become popular in military and collegiate athletic settings. However, little is known regarding the test-retest reliability or, more importantly, the ability of these systems to accurately identify individuals at risk for MSKI. Purpose: To determine the association between scores from a proprietary MMC movement screen test and the likelihood of suffering a subsequent MSKI and establish the test-retest reliability of the MMC system used. Study Design: Cohort study; Level of evidence, 3. Methods: Trainees for the Air Force Special Warfare program underwent MMC screenings immediately before entering the 8-week training course. MSKI data were extracted from a database for the surveillance period for each trainee. Logistic regression analyses were performed to identify associations between baseline MMC scores and the likelihood of suffering any MSKI or, specifically, a lower extremity MSKI. The test-retest portion of the study collected MMC scores from 10 separate participants performing 4 trials of the standard test procedures. Reliability was assessed using intraclass correlation coefficients by a single rater. Results: Overall, 1570 trainees, of whom 800 (51%) suffered an MSKI, were included in the analysis. MMC scores poorly predicted the likelihood of any or a lower extremity MSKI (odds ratio, 1.01-1.02). Further, receiver operating characteristic curve analyses demonstrated poor sensitivity and specificity for prediction of MSKI with MMC scores (area under the curve = 0.53). Finally, intraclass correlation coefficients from the test-retest analysis of MMC scores ranged from 0.157 to 0.602. Conclusion: This MMC system displayed poor to moderate test-retest reliability and did not demonstrate the ability to discriminate between individuals who were and were not likely to suffer an MSKI.

Validity and Intrarater Reliability of a 2-Dimensional Motion Analysis Using a Handheld Tablet Compared With Traditional 3-Dimensional Motion Analysis

2015 ◽  
Vol 24 (4) ◽  
Author(s):  
Barbara C. Belyea ◽  
Ethan Lewis ◽  
Zachary Gabor ◽  
Jill Jackson ◽  
Deborah L. King
Keyword(s):  
Lower Extremity ◽  
Motion Analysis ◽  
Motion Capture ◽  
Knee Flexion ◽  
Motion Capture System ◽  
3D Motion ◽  
3 Dimensional ◽  
Lower Extremity Alignment ◽  
Vertical Jumps ◽  
3D Motion Capture

Context: Lower-extremity landing mechanics have been implicated as a contributing factor in knee pain and injury, yet cost-effective and clinically accessible methods for evaluating movement mechanics are limited. The identification of valid, reliable, and readily accessible technology to assess lower-extremity alignment could be an important tool for clinicians, coaches, and strength and conditioning specialists. Objective: To examine the validity and reliability of using a handheld tablet and movement-analysis application (app) for assessing lower-extremity alignment during a drop vertical-jump task. Design: Concurrent validation. Setting: Laboratory. Participants: 22 healthy college-age subjects (11 women and 11 men, mean age 21 ± 1.4 y, mean height 1.73 ± 0.12 m, mean mass 71 ± 13 kg) with no lower-extremity pathology that prevented safe landing from a drop jump. Intervention: Subjects performed 6 drop vertical jumps that were recorded simultaneously using a 3-dimensional (3D) motion-capture system and a handheld tablet. Main Outcomes Measures: Angles on the tablet were calculated using a motion-analysis app and from the 3D motion-capture system using Visual 3D. Hip and knee angles were measured and compared between both systems. Results: Significant correlations between the tablet and 3D measures for select frontal- and sagittal-plane ranges of motion and angles at maximum knee flexion (MKF) ranged from r = .48 (P = .036) for frontal-plane knee angle at MKF to r = .77 (P < .001) for knee flexion at MKF. Conclusion: Results of this study suggest that a handheld tablet and app may be a reliable method for assessing select lower-extremity joint alignments during drop vertical jumps, but this technology should not be used to measure absolute joint angles. However, sports medicine specialists could use a handheld tablet to reliably record and evaluate lower-extremity movement patterns on the field or in the clinic.

scholarly journals High 1RM Tests Reproducibility and Validity are not Dependent on Training Experience, Muscle Group Tested or Strength Level in Older Women

Sports ◽  
2018 ◽  
Vol 6 (4) ◽  
pp. 171 ◽  
Author(s):  
Matheus Barbalho ◽  
Paulo Gentil ◽  
Rodolfo Raiol ◽  
Fabrício Del Vecchio ◽  
Rodrigo Ramirez-Campillo ◽  
...  
Keyword(s):  
Elderly Women ◽  
High Reliability ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
The Elderly ◽  
Lower Limbs ◽  
Strength Level ◽  
Training Experience ◽  
Intraclass Correlation Coefficients ◽  
Before And After

Background: The maximal one-repetition test (1-RM) is widely used in scientific research; however, there are conflicting results regarding its reproducibility in elderly populations. The present study aimed to analyze the reproducibility of the test both before and after a 12-week training period by using the bench press and leg press 45° 1-RM tests in the elderly, taking into consideration the training experience and strength level of the women. Methods: Elderly women (n = 376; age, 68.5 ± 14.1 years; height, 162.7 ± 5.5 cm; body mass, 71.2 ± 16.0 kg) who underwent ≥3 months of resistance training performed an initial week of familiarization and a second week of testing and retest, with a 48–72 h interval. Results: The results showed that Kappa indices ranged from 0.93 to 0.95, and the intraclass correlation coefficients were 0.99 for both the lower and upper limbs. In addition, minimal detectable changes were found that ranged between 1 and 3%, which means that changes lower than 1 kg could be detected. Conclusion: The present study confirms that the 1-RM test has high reliability and reproducibility in the elderly, for both upper and lower limbs.

High Reliability for Semiautomated 3D Measurements Based on Weightbearing CT Scans

2021 ◽  
pp. 107110072110345
Author(s):  
Peter Kvarda ◽  
Nicola Krähenbühl ◽  
Roman Susdorf ◽  
Arne Burssens ◽  
Roxa Ruiz ◽  
...  
Keyword(s):  
High Reliability ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Level Of Evidence ◽  
3 Dimensional ◽  
Intraclass Correlation Coefficients ◽  
3D Measurements ◽  
Reliable Assessment ◽  
Bland Altman Method ◽  
Treatment Concepts

Background: A reliable assessment of the ankle using weightbearing radiography remains challenging. Semiautomated 3-dimensional (3D) measurements derived from weightbearing computed tomography (WBCT) scans may provide a more reliable approach. Methods: Thirty healthy individuals without any foot and ankle disorder were analyzed. We assessed 6 widely used ankle parameters (4 angles and 2 distances) using either semiautomated 3D (based on WBCT scans) or traditional 2-dimensional (2D; based on conventional radiographs) measurements. The reliability and discrepancy between both techniques were compared using intraclass correlation coefficients and the Bland-Altman method. Results: Five of 6 variables showed a lower reliability when derived from 2D measurements. The mean of 3 variables differed between the techniques: the 3D technique assessed that the talonavicular coverage angle was 18.9 degrees higher, the axial talocalcaneal angle was 5.5 degrees higher, and the talocalcaneal overlap was 3.7 mm lower when compared with 2D measurements. Conclusion: Semiautomated 3D measurements derived from WBCT scans provide more reliable information on ankle alignment compared with 2D measurements based on weightbearing radiographs. Future studies may show to what extent these parameters could contribute to current diagnostic algorithms and treatment concepts. Level of Evidence: Not applicable.

Reliability of Navigated Lower Limb Alignment in High Tibial Osteotomies

2008 ◽  
Vol 36 (11) ◽  
pp. 2179-2186 ◽  
Author(s):  
Patrick Goleski ◽  
Blaine Warkentine ◽  
Darrick Lo ◽  
Cassie Gyuricza ◽  
Daniel Kendoff ◽  
...  
Keyword(s):  
Computed Tomography ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Tibial Slope ◽  
Tibial Rotation ◽  
Limb Alignment ◽  
3 Dimensional ◽  
Intraclass Correlation Coefficients ◽  
Flexion Extension

Background Navigation allows for determination of the mechanical axis of the lower extremity during high tibial osteotomy (HTO) procedures. The objectives of this study were to (1) evaluate the reliability of noninvasive registration with an image-free navigation system for HTO and (2) determine the accuracy of the navigation system to monitor changes in lower limb alignment as compared with alignment measured with a novel 3-dimensional computed tomography method. Hypothesis Navigated limb alignment demonstrates good reliability and accuracy in all 3 planes. Study Design Descriptive laboratory study. Methods Thirteen cadaver legs were used to examine the intra- and interobserver registration reliability of 3 observers. Initial coronal, sagittal, and axial alignment was measured on 6 legs, 3 times each, at intervals >36 hours. Navigated HTOs were then performed on all 13 legs, pre- and postoperative alignment was recorded, and data were compared with equivalent measures obtained by 3-dimensional computed tomography. Reliability and accuracy data were both analyzed using intraclass correlation coefficients with the following established thresholds: good, >0.75; fair, 0.4 to 0.75; and poor, <0.4. Results Intraclass correlation coefficients for intraobserver reliability were categorized as follows: varus-valgus, good; flexion-extension fair; and femoral-tibial rotation, poor. For interobserver reliability, results were varus-valgus, fair; flexion-extension, fair; and femoral-tibial rotation, poor. Intraclass correlation coefficients for navigation accuracy were varus-valgus, good; tibial slope, good; and tibial torsion, poor. Maximum differences in navigation-computed tomography measurements were Δ varus-valgus angle, 4.5°; Δ tibial slope, 8.8°; and Δ tibial torsion, 16.5°. Conclusion and Clinical Relevance Navigation may be reliable and clinically useful for dynamic monitoring of coronal leg alignment but has limits in determination of sagittal and axial plane alignment.

Interobserver Reliability Using the Phonetic Level Evaluation With Severely and Profoundly Hearing-Impaired Children

1991 ◽  
Vol 34 (5) ◽  
pp. 989-999 ◽  
Author(s):  
Stephanie Shaw ◽  
Truman E. Coggins
Keyword(s):  
Interrater Reliability ◽  
Interobserver Reliability ◽  
Intraclass Correlation ◽  
Correlation Coefficients ◽  
Hearing Impaired ◽  
Intraclass Correlation Coefficients ◽  
Assessment Measure ◽  
Impaired Children ◽  
Speech Assessment ◽  
Hearing Impaired Children

This study examines whether observers reliably categorize selected speech production behaviors in hearing-impaired children. A group of experienced speech-language pathologists was trained to score the elicited imitations of 5 profoundly and 5 severely hearing-impaired subjects using the Phonetic Level Evaluation (Ling, 1976). Interrater reliability was calculated using intraclass correlation coefficients. Overall, the magnitude of the coefficients was found to be considerably below what would be accepted in published behavioral research. Failure to obtain acceptably high levels of reliability suggests that the Phonetic Level Evaluation may not yet be an accurate and objective speech assessment measure for hearing-impaired children.

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