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

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.

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Age-Group Differences in Reactive Strength and Measures of Intra-day Reliability in Female International Footballers

International Journal of Strength and Conditioning ◽

10.47206/ijsc.v1i1.44 ◽

2021 ◽

Vol 1 (1) ◽

Author(s):

Brian Doyle ◽

Declan Browne ◽

Dan Horan

Keyword(s):

Soccer Player ◽

Intraclass Correlation ◽

Age Groups ◽

Soccer Players ◽

Group Differences ◽

Age Group ◽

Strength Index ◽

Warm Up ◽

Jump Test ◽

Female Soccer Player

The aim of this present study was to compare the reactive strength index (RSI) characteristics and trial to trial reliability of U17, U19 and Senior female international soccer players. Fifty – seven elite female soccer player participated in the study, (age: 18.1 + 3.1 years; height: 167.5 + 6.3 cm; weight: 61.84 + 7.7 kg). Participants performed 3 maximal repetitions of the 10/5 repeated jump test (10/5RJT) following a specific warm-up and familiarisation protocol. Senior players possessed higher levels of RSI with large effect size present when compared with the U17 (P= 0.043, ES = .97) and U19 (ES = 0.85) age groups. Trivial differences (ES = 0.17) in RSI existed between the U17 and U19 age categories. Trial-to-trial analyses demonstrated 10/5 RJT RSI to possess adequate levels of reliability with a range of mean coefficients of variance (CV) of 3.1 – 7.3 % and intraclass correlation (ICC) between 0.95 – 0.98 present across all three age groups. However, large variations in the between – athlete CV for RSI were revealed ranging from 1 – 27 %, 0.4 – 10.3%, and 1 – 7 % for U17, U19 and senior age groups respectively. These results suggest that age group can distinguish reactive strength capabilities. In addition, female international footballers with higher levels of RSI appear to produce more reliable measures of RSI via the 10/5 RJT.

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Genetic variation in the quantitative levels of an NADP (H)-binding protein (FX) in human erythrocytes

Blood ◽

10.1182/blood.v57.2.209.209 ◽

1981 ◽

Vol 57 (2) ◽

pp. 209-217 ◽

Cited By ~ 4

Author(s):

L Lenzerini ◽

U Benatti ◽

A Morelli ◽

S Pontremoli ◽

A De Flora ◽

...

Keyword(s):

Genetic Variation ◽

Preliminary Data ◽

Binding Protein ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Red Cell ◽

Genetic Origin ◽

Intraclass Correlation Coefficients ◽

The Individual

Abstract FX is a red cell NADP(H)-binding protein that has been well defined biochemically and immunologically but whose function is still unknown. Preliminary data indicated that the levels of this protein are significantly increased in hemizygotes, heterozygotes, and homozygotes for the G6PD Mediterranean mutant, thus raising the question of whether or not the individual variation in FX levels is more or less directly influenced by X-linked genes. The present study, based on a large series of population and family data collected in Sardinia, confirms unequivocally the above mentioned interaction, but shows at the same time that the variances in FX levels “between sibships” are 2–3 times larger than those “within sibships,” when the analysis is done separately for the G6PD-normal or the G6PD-deficient sibs. From the comparison of the interclass and intraclass correlation coefficients, it appears that about 60% of the total variation of FX is of genetic origin. Moreover, the FX levels of children, analyzed in a pairwise manner, were found to be more positively correlated with those of their fathers (r = 0.39) than with those of their maternal grandfathers (0.20). This latter finding obviously favors the conclusion that “autosomal”; rather than “X-linked” genes are involved in the determination of the FX levels.

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Determination of Facial Symmetry in Unilateral Cleft Lip and Palate Patients from Three-Dimensional Data: Technical Report and Assessment of Measurement Errors

The Cleft Palate-Craniofacial Journal ◽

10.1597/04-138.1 ◽

2006 ◽

Vol 43 (2) ◽

pp. 129-137 ◽

Cited By ~ 35

Author(s):

Emeka Nkenke ◽

Bernhard Lehner ◽

Manuel Kramer ◽

Gerd Haeusler ◽

Stefanie Benz ◽

...

Keyword(s):

Measurement Errors ◽

Cleft Lip ◽

Cleft Lip And Palate ◽

Intraclass Correlation ◽

Three Dimensional ◽

Correlation Coefficients ◽

Intraclass Correlation Coefficients ◽

Surface Areas ◽

Technical Report

Objective To assess measurement errors of a novel technique for the three-dimensional determination of the degree of facial symmetry in patients suffering from unilateral cleft lip and palate malformations. Design Technical report, reliability study. Setting Cleft Lip and Palate Center of the University of Erlangen-Nuremberg, Erlangen, Germany. Patients The three-dimensional facial surface data of five 10-year-old unilateral cleft lip and palate patients were subjected to the analysis. Distances, angles, surface areas, and volumes were assessed twice. Main Outcome Measures Calculations were made for method error, intraclass correlation coefficient, and repeatability of the measurements of distances, angles, surface areas, and volumes. Results The method errors were less than 1 mm for distances and less than 1.5° for angles. The intraclass correlation coefficients showed values greater than .90 for all parameters. The repeatability values were comparable for cleft and noncleft sides. Conclusion The small method errors, high intraclass correlation coefficients, and comparable repeatability values for cleft and noncleft sides reveal that the new technique is appropriate for clinical use.

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The 10/5 Repeated Jumps Test: Are 10 Repetitions and Three Trials Necessary?

Biomechanics ◽

10.3390/biomechanics1010001 ◽

2020 ◽

Vol 1 (1) ◽

pp. 1-14

Author(s):

Callum Stratford ◽

Thomas Dos’Santos ◽

John J. McMahon

Keyword(s):

Repeated Measures ◽

Intraclass Correlation ◽

Force Plate ◽

Correlation Coefficients ◽

Pairwise Comparisons ◽

Strength Index ◽

Intraclass Correlation Coefficients ◽

Coefficients Of Variation ◽

Repeated Measures Analysis ◽

Ground Contact Time

The purpose of this study was to identify whether ten repetitions and three trials were necessary to achieve stability in peak reactive strength index (RSI) during the 10/5 repeated jumps test (RJT). Twenty-five males, from multiple sports, performed three trials of the RJT on an in-ground force plate, with 90 seconds’ rest between trials. Intraclass correlation coefficients (ICC = 0.916–0.986) and coefficients of variation (CV ≤ 14.5%) were considered acceptable for all variables. Repeated-measures analysis of variance and Freidman’s tests revealed large and significant differences (p ≤ 0.006, η2 = 0.159–0.434, power ≥ 0.859) in ground contact time (GCT), jump height (JH), and subsequently RSI both between trials and repetitions. Pairwise comparisons revealed that repetitions 1–3 produced longer GCTs (p ≤ 0.05, d = 0.41–1.40), lower JHs (p ≤ 0.05, d = 0.31–0.56), and lower RSI values (p ≤ 0.05, d = 0.35–1.24). The shortest GCTs, greatest JHs and greater RSIs occurred between repetitions 7 and 10, with approximately 60% of peak RSIs occurring during these ranges. The sequential estimate technique revealed that seven repetitions were needed to attain stability in mean peak RSI. Non-significant (p = 0.554) and negligible differences (d ≤ 0.09) in the five best RSIs between trials were noted. One trial of the 10/5 RJT is sufficient to evaluate peak RSI in athletes and should reduce data collection time and fatigue.

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

Sensors ◽

10.3390/s21237954 ◽

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.

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

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2018-0684 ◽

2019 ◽

Vol 14 (4) ◽

pp. 540-543 ◽

Cited By ~ 12

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.

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Genetic variation in the quantitative levels of an NADP (H)-binding protein (FX) in human erythrocytes

Blood ◽

10.1182/blood.v57.2.209.bloodjournal572209 ◽

1981 ◽

Vol 57 (2) ◽

pp. 209-217

Author(s):

L Lenzerini ◽

U Benatti ◽

A Morelli ◽

S Pontremoli ◽

A De Flora ◽

...

Keyword(s):

Genetic Variation ◽

Preliminary Data ◽

Binding Protein ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Red Cell ◽

Genetic Origin ◽

Intraclass Correlation Coefficients ◽

The Individual

FX is a red cell NADP(H)-binding protein that has been well defined biochemically and immunologically but whose function is still unknown. Preliminary data indicated that the levels of this protein are significantly increased in hemizygotes, heterozygotes, and homozygotes for the G6PD Mediterranean mutant, thus raising the question of whether or not the individual variation in FX levels is more or less directly influenced by X-linked genes. The present study, based on a large series of population and family data collected in Sardinia, confirms unequivocally the above mentioned interaction, but shows at the same time that the variances in FX levels “between sibships” are 2–3 times larger than those “within sibships,” when the analysis is done separately for the G6PD-normal or the G6PD-deficient sibs. From the comparison of the interclass and intraclass correlation coefficients, it appears that about 60% of the total variation of FX is of genetic origin. Moreover, the FX levels of children, analyzed in a pairwise manner, were found to be more positively correlated with those of their fathers (r = 0.39) than with those of their maternal grandfathers (0.20). This latter finding obviously favors the conclusion that “autosomal”; rather than “X-linked” genes are involved in the determination of the FX levels.

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Reliability of Navigated Lower Limb Alignment in High Tibial Osteotomies

The American Journal of Sports Medicine ◽

10.1177/0363546508319314 ◽

2008 ◽

Vol 36 (11) ◽

pp. 2179-2186 ◽

Cited By ~ 29

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.

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

Journal of Speech Language and Hearing Research ◽

10.1044/jshr.3405.989 ◽

1991 ◽

Vol 34 (5) ◽

pp. 989-999 ◽

Cited By ~ 6

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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Comparative Responses to Squats Completed with Free Weights and an Exoskeleton

Gravitational and Space Research ◽

10.2478/gsr-2016-0005 ◽

2020 ◽

Vol 4 (1) ◽

pp. 51-63

Author(s):

Peter Neuhaus ◽

Chris Jumonville ◽

Rachel A. Perry ◽

Roman Edwards ◽

Jake L. Martin ◽

...

Keyword(s):

Data Collection ◽

Female Athletes ◽

Pearson Correlation ◽

Correlation Coefficients ◽

Actual Data ◽

Limited Data ◽

Comparative Similarity ◽

Insufficient Amount ◽

Force Data ◽

Familiarization Session

AbstractTo assess the comparative similarity of squat data collected as they wore a robotic exoskeleton, female athletes (n=14) did two exercise bouts spaced 14 days apart. Data from their exoskeleton workout was compared to a session they did with free weights. Each squat workout entailed a four-set, four-repetition paradigm with 60-second rest periods. Sets for each workout involved progressively heavier (22.5, 34, 45.5, 57 kg) loads. The same physiological, perceptual, and exercise performance dependent variables were measured and collected from both workouts. Per dependent variable, Pearson correlation coefficients, t-tests, and Cohen's d effect size compared the degree of similarity between values obtained from the exoskeleton and free weight workouts. Results show peak O2, heart rate, and peak force data produced the least variability. In contrast, far more inter-workout variability was noted for peak velocity, peak power, and electromyography (EMG) values. Overall, an insufficient amount of comparative similarity exists for data collected from both workouts. Due to the limited data similarity, the exoskeleton does not exhibit an acceptable degree of validity. Likely the cause for the limited similarity was due to the brief amount of familiarization subjects had to the exoskeleton prior to actual data collection. A familiarization session that accustomed subjects to squats done with the exoskeleton prior to actual data collection may have considerably improved the validity of data obtained from that device.

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