Validity and Reliability of an Alternative Method for Measuring Power Output During Six-Second All-out Cycling

In a laboratory setting where both a mechanically-braked cycling ergometer and a motion analysis (MA) system are available, flywheel angular displacement can be estimated by using MA. The purpose of this investigation was to assess the validity and reliability of a MA method for measuring maximal power output (Pmax) in comparison with a force transducer (FT) method. Eight males and eight females undertook three identical sessions, separated by 4 to 6 days; the first being a familiarization session. Individuals performed three 6-second sprints against 50% of the maximal resistance to complete two pedal revolutions with a 3-minute rest between trials. Power was determined independently using both MA and FT analyses. Validity: MA recorded significantly higher Pmaxthan FT (P< .05). Bland–Altman plots showed that there was a systematic bias in the difference between the measures of the two systems. This difference increased as power increased. Repeatability: Intraclass correlation coefficients were on average 0.90 ± 0.05 in males and 0.85 ± 0.08 in females. Measuring Pmaxby MA, therefore, is as appropriate for use in exercise physiology research as Pmaxmeasured by FT, provided that a bias between these measurements methods is allowed for.

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Valid and Reliable Barbell Velocity Estimation Using an Inertial Measurement Unit

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18179170 ◽

2021 ◽

Vol 18 (17) ◽

pp. 9170

Author(s):

Steffen Held ◽

Ludwig Rappelt ◽

Jan-Philip Deutsch ◽

Lars Donath

Keyword(s):

Inertial Measurement Unit ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Velocity Estimation ◽

Measurement Unit ◽

Systematic Bias ◽

Validity And Reliability ◽

Inertial Measurement ◽

Intraclass Correlation Coefficients ◽

Reliability Indicators

The accurate assessment of the mean concentric barbell velocity (MCV) and its displacement are crucial aspects of resistance training. Therefore, the validity and reliability indicators of an easy-to-use inertial measurement unit (VmaxPro®) were examined. Nineteen trained males (23.1 ± 3.2 years, 1.78 ± 0.08 m, 75.8 ± 9.8 kg; Squat 1-Repetition maximum (1RM): 114.8 ± 24.5 kg) performed squats and hip thrusts (3–5 sets, 30 repetitions total, 75% 1RM) on two separate days. The MCV and displacement were simultaneously measured using VmaxPro® and a linear position transducer (Speed4Lift®). Good to excellent intraclass correlation coefficients (0.91 < ICC < 0.96) with a small systematic bias (p < 0.001; ηp2 < 0.50) for squats (0.01 ± 0.04 m·s−1) and hip thrusts (0.01 ± 0.05 m·s−1) and a low limit of agreement (LoA < 0.12 m·s−1) indicated an acceptable validity. The within- and between-day reliability of the MCV revealed good ICCs (0.55 < ICC < 0.91) and a low LoA (<0.16 m·s−1). Although the displacement revealed a systematic bias during squats (p < 0.001; ηp2 < 0.10; 3.4 ± 3.4 cm), no bias was detectable during hip thrusts (p = 0.784; ηp2 < 0.001; 0.3 ± 3.3 cm). The displacement showed moderate to good ICCs (0.43 to 0.95) but a high LoA (7.8 to 10.7 cm) for the validity and (within- and between-day) reliability of squats and hip thrusts. The VmaxPro® is considered to be a valid and reliable tool for the MCV assessment.

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Relative validity and reliability of a novel diet quality assessment tool for athletes: the Athlete Diet Index

British Journal Of Nutrition ◽

10.1017/s000711452000416x ◽

2020 ◽

pp. 1-13

Author(s):

Louise Capling ◽

Janelle A. Gifford ◽

Kathryn L. Beck ◽

Victoria M. Flood ◽

Fiona Halar ◽

...

Keyword(s):

Diet Quality ◽

Assessment Tool ◽

Intraclass Correlation ◽

Rank Correlation ◽

Correlation Coefficients ◽

Systematic Bias ◽

Validity And Reliability ◽

Food Record ◽

Good Reliability ◽

Relative Validity

Abstract Diet quality indices are a practical, cost-effective method to evaluate dietary patterns, yet few have investigated diet quality in athletes. This study describes the relative validity and reliability of the recently developed Athlete Diet Index (ADI). Participants completed the electronic ADI on two occasions, 2 weeks apart, followed by a 4-d estimated food record (4-dFR). Relative validity was evaluated by directly comparing mean scores of the two administrations (mAdm) against scores derived from 4-dFR using Spearman’s rank correlation coefficient and Bland–Altman (B–A) plots. Construct validity was investigated by comparing mAdm scores and 4-dFR-derived nutrient intakes using Spearman’s coefficient and independent t test. Test–retest reliability was assessed using paired t test, intraclass correlation coefficients (ICC) and B–A plots. Sixty-eight elite athletes (18·8 (sd 4·2) years) from an Australian sporting institute completed the ADI on both occasions. Mean score was 84·1 (sd 15·2; range 42·5–114·0). The ADI had good reliability (ICC = 0·80, 95 % CI 0·69, 0·87; P < 0·001), and B–A plots (mean 1·9; level of agreement −17·8, 21·7) showed no indication of systematic bias (y = 4·57–0·03 × x) (95 % CI −0·2, 0·1; P = 0·70). Relative validity was evaluated in fifty athletes who completed all study phases. Comparison of mAdm scores with 4-dFR-derived scores was moderate (rs 0·69; P < 0·001) with no systematic bias between methods of measurement (y = 6·90–0·04 × x) (95 % CI −0·3, 0·2; P = 0·73). Higher scores were associated with higher absolute nutrient intake consistent with a healthy dietary pattern. The ADI is a reliable tool with moderate validity, demonstrating its potential for application to investigate the diet quality of athletes.

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Validity and Reliability of the Cycleops Hammer Cycle Ergometer

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2017-0403 ◽

2018 ◽

Vol 13 (7) ◽

pp. 853-859 ◽

Cited By ~ 2

Author(s):

José R. Lillo-Bevia ◽

Jesús G. Pallarés

Keyword(s):

Power Output ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Cycle Ergometer ◽

Validity And Reliability ◽

Exercise Tests ◽

Intraclass Correlation Coefficients ◽

Graded Exercise ◽

Marginal Values ◽

Srm System

Purpose: To validate the new drive indoor trainer Hammer designed by Cycleops®. Methods: A total of 11 cyclists performed 44 randomized and counterbalanced graded exercise tests (100–500 W) at 70-, 85-, and 100-rpm cadences in seated and standing positions on 3 different Hammer units, while a scientific SRM system continuously recorded cadence and power output data. Results: No significant differences were detected between the 3 Hammer devices and the SRM for any workload, cadence, or pedaling condition (P value between 1.00 and .350), except for some minor differences (P = .03 and .04) found in the Hammer 1 at low workloads and for Hammer 2 and 3 at high workloads, all in seated position. Strong intraclass correlation coefficients were found between the power output values recorded by the Hammers and the SRM (≥.996; P = .001), independently from the cadence condition and seated position. Bland–Altman analysis revealed low bias (−5.5 to 3.8) and low SD of bias (2.5–5.3) for all testing conditions, except marginal values found for the Hammer 1 at high cadences and seated position (9.6 [6.6]). High absolute reliability values were detected for the 3 Hammers (150–500 W; coefficient of variation <1.2%; SEM <2.1). Conclusions: This new Cycleops trainer is a valid and reliable device to drive and measure power output in cyclists, providing an alternative to larger and more expensive laboratory ergometers and allowing cyclists to use their own bicycles.

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Validity and Reliability of a New Device (WIMU®) for Measuring Hamstring Muscle Extensibility

International Journal of Sports Medicine ◽

10.1055/s-0043-108998 ◽

2017 ◽

Vol 38 (09) ◽

pp. 691-695 ◽

Cited By ~ 6

Author(s):

José Muyor

Keyword(s):

Standard Error ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Systematic Bias ◽

Hamstring Muscle ◽

Validity And Reliability ◽

Retest Reliability ◽

New Device ◽

Test Retest Reliability ◽

Straight Leg Raise

AbstractThe aims of the current study were 1) to evaluate the validity of the WIMU® system for measuring hamstring muscle extensibility in the passive straight leg raise (PSLR) test using an inclinometer for the criterion and 2) to determine the test-retest reliability of the WIMU® system to measure hamstring muscle extensibility during the PSLR test. 55 subjects were evaluated on 2 separate occasions. Data from a Unilever inclinometer and WIMU® system were collected simultaneously. Intraclass correlation coefficients (ICCs) for the validity were very high (0.983–1); a very low systematic bias (−0.21°–−0.42°), random error (0.05°–0.04°) and standard error of the estimate (0.43°–0.34°) were observed (left–right leg, respectively) between the 2 devices (inclinometer and the WIMU® system). The R2 between the devices was 0.999 (p<0.001) in both the left and right legs. The test-retest reliability of the WIMU® system was excellent, with ICCs ranging from 0.972–0.995, low coefficients of variation (0.01%), and a low standard error of the estimate (0.19–0.31°). The WIMU® system showed strong concurrent validity and excellent test-retest reliability for the evaluation of hamstring muscle extensibility in the PSLR test.

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Assessment of reliability and validity of the 5-scale grading system of the point-of-care immunoassay for tear matrix metalloproteinase-9

Scientific Reports ◽

10.1038/s41598-021-92020-6 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Minjeong Kim ◽

Ja Young Oh ◽

Seon Ha Bae ◽

Seung Hyeun Lee ◽

Won Jun Lee ◽

...

Keyword(s):

Matrix Metalloproteinase ◽

Calibration Curve ◽

Point Of Care ◽

Interobserver Reliability ◽

Intraclass Correlation ◽

Reliability And Validity ◽

Correlation Coefficients ◽

Grading System ◽

Intraclass Correlation Coefficients ◽

The Difference

AbstractWe evaluated the reliability and validity of the 5-scale grading system to interpret the point-of-care immunoassay for tear matrix metalloproteinase (MMP)-9. Six observers graded red bands of photographs of the readout window in MMP-9 immunoassay kit (InflammaDry) two times with 2-week interval based on the 5-scale grading system (i.e. grade 0–4). Interobserver and intraobserver reliability were evaluated using intraclass correlation coefficients. The interobserver agreements were analyzed according to the severity of tear MMP-9 expression. To validate the system, a concentration calibration curve was made using MMP-9 solutions with reference concentrations, then the distribution of MMP-9 concentrations was analyzed according to the 5-scale grading system. Both intraobserver and interobserver reliability was excellent. The readout grades were significantly correlated with the quantified colorimetric densities. The interobserver variance of readout grades had no correlation with the severity of the measured densities. The band density continued to increase up to a maximal concentration (i.e. 5000 ng/mL) according to the calibration curve. The difference of grades reflected the change of MMP-9 concentrations sensitively, especially between grade 2 and 4. Together, our data indicate that the subjective 5-scale grading system in the point-of-care MMP-9 immunoassay is an easy and reliable method with acceptable accuracy.

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An investigation into the validity and reliability of the Chinese version of Spinal Cord Independence Measure III (SCIM III)

Clinical Rehabilitation ◽

10.1177/0269215520966703 ◽

2020 ◽

pp. 026921552096670

Author(s):

Huayi Xing ◽

Nan Liu ◽

Fin Biering-Sørensen

Keyword(s):

Spinal Cord ◽

Spinal Cord Injury ◽

Barthel Index ◽

Pearson Correlation ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Chinese Version ◽

Validity And Reliability ◽

Post Injury ◽

Cord Injury

Objective: To investigate the validity and reliability of a Chinese version of Spinal Cord Independence Measure III (SCIM III) in individuals with spinal cord injury. Design: Study on psychometric properties. Setting: An inpatient rehabilitation facility in China. Subjects: 102 participants with spinal cord injury. Mean (SD) age was 48.8 (15.6) years; tetraplegia/paraplegia ratio was 50/52; median time post injury was 2 months. Intervention: SCIM III was translated into Chinese. Chinese versions of Barthel Index and SCIM III were filled out for each participant by Rater 1. SCIM III was then administered by Rater 2 after 24 hours ( n = 67) and 7 days ( n = 65). Main Measures: Validity, inter-rater/test-retest reliability, and internal consistency of the Chinese version of SCIM III. Results: The total scores between the two raters were similar (mean ± SD: 33.8 ± 25.8 vs 33.8 ± 25.5, P = 0.95). Total agreement between the raters in each item was >80%, with both Pearson and intraclass correlation coefficients >0.97 ( P < 0.01) for each subscale and total score. The Pearson correlation coefficients of the two independent assessments performed by Rater 2 were also >0.97 ( P < 0.01) for each subscale and the total score. Cronbach α was >0.7 for each subscale and the total score for both raters. High consistency was found between Barthel Index and SCIM III total scores (Pearson correlation coefficient = 0.88, P < 0.01). Conclusion: The Chinese version of SCIM III is valid and reliable for the functional assessment of patients with SCI.

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A constant-load ergometer for measuring peak power output and fatigue

Journal of Applied Physiology ◽

10.1152/jappl.1988.65.5.2343 ◽

1988 ◽

Vol 65 (5) ◽

pp. 2343-2348 ◽

Cited By ~ 18

Author(s):

J. H. Williams ◽

W. S. Barnes ◽

J. F. Signorile

Keyword(s):

Power Output ◽

Peak Power ◽

Intraclass Correlation ◽

Average Power ◽

Load Cycle ◽

Constant Load ◽

Load Cell ◽

Peak Power Output ◽

Maximal Power Output ◽

Power Curves

A constant-load cycle ergometer was constructed that allows maximal power output to be measured for each one-half pedal revolution during brief, high-intensity exercise. To determine frictional force, an electronic load cell was attached to the resistance strap and the ergometer frame. Dead weights were attached to the strap's free end. Flywheel velocity was recorded by means of a magnetic switch and two magnets placed on the pedal sprocket. Pedaling resulted in magnetically activated switch closures, which produced two electronic pulses per pedal revolution. Pulses and load cell output were recorded (512 Hz), digitized, and stored on disk via microcomputer. Power output was later computed for each pair of adjacent pulses, representing average power per one-half pedal revolution. Power curves generated for each subject were analyzed for peak power output (the highest one-half pedal revolution average), time to peak power, power fatigue rate and index, average power, and total work. Thirty-eight males performed two 15-s tests separated by 15 min (n = 16) or 48 h (n = 22). Peak power output ranged from 846.0 to 1,289.1 W. Intraclass correlation analysis revealed high test-retest reliability for all parameters recorded on the same or different days (R = 0.91-0.97). No significant differences (P greater than 0.05) were noted between parameter means of the first and second tests. These results indicate that the ergometer described provides a means for conveniently and reliably assessing short-term power output and fatigue.

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The Reliability and Validity of the Loadsol® under Various Walking and Running Conditions

Sensors ◽

10.3390/s19020265 ◽

2019 ◽

Vol 19 (2) ◽

pp. 265 ◽

Cited By ~ 12

Author(s):

Kristen Renner ◽

DS Williams ◽

Robin Queen

Keyword(s):

Reliable Method ◽

Loading Rate ◽

Reaction Force ◽

Intraclass Correlation ◽

Reliability And Validity ◽

Correlation Coefficients ◽

Validity And Reliability ◽

Intraclass Correlation Coefficients ◽

Single Sensor ◽

Force Data

The assessment of loading during walking and running has historically been limited to data collection in laboratory settings or with devices that require a computer connection. This study aims to determine if the loadsol®—a single sensor wireless insole—is a valid and reliable method of assessing force. Thirty (17 male and 13 female) recreationally active individuals were recruited for a two visit study where they walked (1.3 m/s) and ran (3.0 and 3.5 m/s) at a 0%, 10% incline, and 10% decline, with the visits approximately one week apart. Ground reaction force data was collected on an instrumented treadmill (1440 Hz) and with the loadsol® (100 Hz). Ten individuals completed the day 1 protocol with a newer 200 Hz loadsol®. Intraclass correlation coefficients (ICC3,k) were used to assess validity and reliability and Bland–Altman plots were generated to better understand loadsol® validity. Across conditions, the peak force ICCs ranged from 0.78 to 0.97, which increased to 0.84–0.99 with the 200 Hz insoles. Similarly, the loading rate ICCs improved from 0.61 to 0.97 to 0.80–0.96 and impulse improved from 0.61 to 0.97 to 0.90–0.97. The 200 Hz insoles may be needed for loading rate and impulse in running. For both walking and running, the loadsol® has excellent between-day reliability (>0.76).

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Validity and Reliability of the Huet Questionnaire to Assess Maximal Oxygen Uptake

Canadian Journal of Applied Physiology ◽

10.1139/h04-040 ◽

2004 ◽

Vol 29 (5) ◽

pp. 623-638 ◽

Cited By ~ 14

Author(s):

Damien Trivel ◽

Paul Calmels ◽

Luc Léger ◽

Thierry Busso ◽

Xavier Devillard ◽

...

Keyword(s):

Oxygen Uptake ◽

Maximal Oxygen Uptake ◽

High Reliability ◽

Stress Test ◽

Intraclass Correlation ◽

Correlation Coefficients ◽

Epidemiological Studies ◽

Cycle Ergometer ◽

Sample Population ◽

Validity And Reliability

The usual fitness tests available to assess maximal oxygen uptake [Formula: see text] a key fitness component, are not particularly useful for epidemiological studies. Questionnaires to assess [Formula: see text] however, are simple, easy to use, and inexpensive. In 1986, Huet developed such a French general questionnaire, which now also has an English version. Its simplicity is interesting as it could be used to survey large populations. The purpose of this study was to assess the validity and reliability of this Huet questionnaire in a sample of healthy French volunteers. A total of 108 subjects were included in this study, 88 males and 20 females. The validity of the questionnaire was checked using correlation coefficients and a Bland-Altman plot between questionnaire estimations and measures of [Formula: see text] obtained with a stress test on a cycle ergometer. An intraclass correlation coefficient (ICC) was also calculated to determine the reliability of the questionnaire. Significant correlation was obtained with the Huet questionnaire and measured [Formula: see text] (r2 = 0.77, p = 0.0001, SEE = 5.97 ml•kg−1•min−1, n = 108). The ICC showed very high reliability (ICC = 0.988, n = 21). The Huet questionnaire is an easy, rapidly administered tool that correlated highly with [Formula: see text] in this sample population. Key words: physical activity, epidemiology, evaluation

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Reproducibility and reliability of three-dimensional soft tissue landmark identification using three-dimensional stereophotogrammetry

The Angle Orthodontist ◽

10.2319/120715-833.1 ◽

2016 ◽

Vol 86 (6) ◽

pp. 1004-1009 ◽

Cited By ~ 14

Author(s):

Asli Baysal ◽

Ahmet Oguz Sahan ◽

Mehmet Ali Ozturk ◽

Tancan Uysal

Keyword(s):

Soft Tissue ◽

Statistical Significance ◽

Intraclass Correlation ◽

Three Dimensional ◽

Correlation Coefficients ◽

Intraclass Correlation Coefficients ◽

Paired Samples ◽

Landmark Identification ◽

The Difference ◽

Intraexaminer Reliability

ABSTRACT Objective: To evaluate the intraexaminer repeatability and interexaminer reproducibility of soft tissue landmarks on three-dimensional (3-D) stereophogrammetric images. Materials and Methods: Thirty-four stereophotogrammetric images were taken and 19 soft tissue points were identified. The images were obtained using the 3-DMD Face (3-DMD TM Ltd, Atlanta, Ga) system. Two examiners marked 34 images manually with a mouse-driven cursor 4 weeks apart. Intraexaminer marking differences were calculated and classified as <0.5 mm, 0.5–1 mm, and >1 mm. Intraclass correlation coefficients were calculated for intraexaminer reliability. A paired-samples t-test was used to evaluate the difference between the examiners. Interexaminer reproducibility was evaluated by kappa analysis. Statistical significance was set at P < .05. Results: Only one landmark (labiale superior) had an intraexaminer marking difference less than 0.5 mm. Existing landmarks had an intraexaminer difference less than 1 mm, but higher than 0.5 mm. The intraclass correlation coefficients (ICCs) indicated good intraexaminer repeatability for both observers. The ICC range for examiners 1 and 2 was 0.986–1.000 and 0.990–1.000, respectively. Kappa scores showed good interexaminer agreement, especially on the z-axis. Conclusions: Except labiale superior, the soft tissue landmarks used in this study were shown to have moderate reproducibility, but the difference between the landmarks was less than 1 mm, and they had clinically acceptable reproducibility.

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