Reliability and concurrent validity of the Velowin optoelectronic system to measure movement velocity during the free-weight back squat

The objective of this study was to explore the reliability and concurrent validity of the Velowin optoelectronic system to measure movement velocity during the free-weight back squat exercise. Thirty-one men (age = 27.5 ± 3.2 years; body height = 1.76 ± 0.15 m; body mass: 78.3 ± 7.6 kg) were evaluated in a single session against five different loads (20, 40, 50, 60 and 70 kg) and three velocity variables (mean velocity, mean propulsive velocity and maximum velocity) were recorded simultaneously by a linear velocity transducer (T-Force; gold-standard) and a camera-based optoelectronic system (Velowin). The main findings revealed that (1) the three velocity variables were determined with a high and comparable reliability by both the T-Force and Velowin systems (median coefficient of variation of the five loads: T-Force: mean velocity = 4.25%, mean propulsive velocity = 4.49% and maximum velocity = 3.45%; Velowin: mean velocity = 4.29%, mean propulsive velocity = 4.60% and maximum velocity = 4.44%), (2) the maximum velocity was the most reliable variable when obtained by the T-force ( p < 0.05), but no significant differences in the reliability of the variables were observed for the Velowin ( p > 0.05) and (3) high correlations were observed for the values of mean velocity ( r = 0.976), mean propulsive velocity ( r = 0.965) and maximum velocity ( r = 0.977) between the T-Force and Velowin systems. Collectively, these results support the Velowin as a reliable and valid system for the measurement of movement velocity during the free-weight back squat exercise.

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The Reliability of Individualized Load–Velocity Profiles

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2017-0610 ◽

2018 ◽

Vol 13 (6) ◽

pp. 763-769 ◽

Cited By ~ 24

Author(s):

Harry G. Banyard ◽

Kazunori Nosaka ◽

Alex D. Vernon ◽

G. Gregory Haff

Keyword(s):

Linear Regression ◽

Peak Velocity ◽

Intraclass Correlation ◽

Velocity Profiles ◽

Mean Velocity ◽

Movement Velocity ◽

Repetition Maximum ◽

Back Squat ◽

Free Weight ◽

Order Polynomial

Purpose: To examine the reliability of peak velocity (PV), mean propulsive velocity (MPV), and mean velocity (MV) in the development of load–velocity profiles (LVP) in the full-depth free-weight back squat performed with maximal concentric effort. Methods: Eighteen resistance-trained men performed a baseline 1-repetition maximum (1-RM) back-squat trial and 3 subsequent 1-RM trials used for reliability analyses, with 48-h intervals between trials. 1-RM trials comprised lifts from 6 relative loads including 20%, 40%, 60%, 80%, 90%, and 100% 1-RM. Individualized LVPs for PV, MPV, or MV were derived from loads that were highly reliable based on the following criteria: intraclass correlation coefficient (ICC) >.70, coefficient of variation (CV) ≤10%, and Cohen d effect size (ES) <0.60. Results: PV was highly reliable at all 6 loads. MPV and MV were highly reliable at 20%, 40%, 60%, 80%, and 90% but not 100% 1-RM (MPV: ICC = .66, CV = 18.0%, ES = 0.10, SEM = 0.04 m·s−1; MV: ICC = .55, CV = 19.4%, ES = 0.08, SEM = 0.04 m·s−1). When considering the reliable ranges, almost perfect correlations were observed for LVPs derived from PV20–100% (r = .91–.93), MPV20–90% (r = .92–.94), and MV20–90% (r = .94–.95). Furthermore, the LVPs were not significantly different (P > .05) between trials or movement velocities or between linear regression versus 2nd-order polynomial fits. Conclusions: PV20–100%, MPV20–90%, and MV20–90% are reliable and can be utilized to develop LVPs using linear regression. Conceptually, LVPs can be used to monitor changes in movement velocity and employed as a method for adjusting sessional training loads according to daily readiness.

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Validity and reliability of the WIMU® system to measure barbell velocity during the half-squat exercise

Proceedings of the Institution of Mechanical Engineers Part P Journal of Sports Engineering and Technology ◽

10.1177/1754337119831890 ◽

2019 ◽

Vol 233 (3) ◽

pp. 408-415 ◽

Cited By ~ 1

Author(s):

Felipe García-Pinillos ◽

Pedro A Latorre-Román ◽

Fernando Valdivieso-Ruano ◽

Carlos Balsalobre-Fernández ◽

Juan A Párraga-Montilla

Keyword(s):

Gold Standard ◽

Concurrent Validity ◽

Pearson Correlation ◽

Maximum Velocity ◽

Systematic Bias ◽

Loading Test ◽

Mean Velocity ◽

Velocity Relationship ◽

Squat Exercise ◽

The Mean

This study aimed at determining the reliability and concurrent validity of the WIMU® system when measuring barbell velocity during the half-squat exercise by comparing data with the gold standard. A total of 19 male competitive powerlifters performed an incremental loading test using the half-squat exercise. The mean velocity, mean propulsive velocity and maximum velocity of all repetitions were recorded through both WIMU and T-Force systems. As a measure of reliability, coefficient of variations ranged from 6%–17% and standard error of means ranged from 0.02–0.11 m/s, showing very close reliability of data from both devices. Validity, in terms of coefficient of correlations and pairwise comparisons, was also tested. Except for some relative loads, the Pearson correlation analysis revealed significant correlations between both devices for mean velocity, mean propulsive velocity and maximum velocity (r > 0.6, p < 0.05). The mean velocity, mean propulsive velocity and maximum velocity were underestimated for the WIMU system compared to T-Force data at some points of the load–velocity relationship. The linear regression models performed revealed a strong load–velocity relationship in the half-squat exercise for each individual using mean velocity, mean propulsive velocity and maximum velocity, regardless of the instrument used (R2 > 0.77 in all cases). Bland–Altman plots revealed low systematic bias (≤0.06 m s−1) and random error (≤0.07 m s−1) for the mean velocity and mean propulsive velocity obtained from the WIMU system as compared to the T-Force, while the maximum velocity resulted in an underestimation by the WIMU system (–0.16 m s−1) as compared to the linear position transducer system. The results indicate that the WIMU system is a reliable tool for tracking barbell velocity in the half squat, but these data also reveal some limitations regarding its concurrent validity as compared to the gold standard, with velocity measures slightly underestimated in the tested conditions.

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Reliability and concurrent validity of the PUSH Band™ 2.0 to measure barbell velocity during the free-weight and Smith machine squat exercises

Proceedings of the Institution of Mechanical Engineers Part P Journal of Sports Engineering and Technology ◽

10.1177/17543371211024018 ◽

2021 ◽

pp. 175433712110240

Author(s):

Alejandro Pérez-Castilla ◽

Amador García-Ramos ◽

Luis Miguel Gijón-Nieto ◽

Aitor Marcos-Blanco ◽

Felipe García-Pinillos

Keyword(s):

Concurrent Validity ◽

Initial Assessment ◽

Mean Velocity ◽

Free Weight ◽

Velocity Transducer ◽

Squat Exercise ◽

Standard Linear ◽

The Mean ◽

Test Retest Reliability ◽

Acceptable Reliability

The aim of this study was to examine the test-retest reliability and concurrent validity of the PUSH Band™ 2.0 to measure barbell’s velocity during unconstrained (free-weights) and constrained (Smith machine) squat exercises. After an initial assessment of the Smith machine squat one-repetition maximum (1RM), 24 resistance-trained males completed one or two testing sessions separated by 7 days. In one session, the squat was performed with free-weights ( n = 22), while in another session, the Smith machine was used ( n = 16). Both testing sessions consisted of two blocks of eight repetitions (three repetitions at 45%1RM, three repetitions at 65%1RM, and two repetitions at 85%1RM). The mean velocity of the lifting phase was simultaneously recorded with the PUSH Band™ 2.0 and a gold-standard linear velocity transducer (T-Force® System). The PUSH Band™ 2.0 generally revealed an acceptable reliability (CVrange = 5.81%–13.14%), but the reliability was always greater for the T-Force® System (CVrange = 2.95%–7.86%). Regardless of the squat exercise, the concurrent validity of the PUSH Band™ 2.0 with respect to the T-Force® System was generally low at 45%1RM (ESrange = 0.18–0.33; rrange = 0.58–0.75; SEErange = 0.04–0.05 ms−1 and 4.2%–6.0%), 65%1RM (ESrange = 0.26–0.44; rrange = 0.63–0.82; SEErange = 0.04–0.06 ms−1 and 6.0%–9.2%), and 85%1RM (ESrange = 0.61–0.64; rrange = 0.66–0.82; SEErange = 0.05–0.07 ms−1 and 11.4%–16.0%). Taken together, these results suggest that the PUSH Band™ 2.0 is a reliable, but not valid, wearable technology to measure the barbell velocity during the free-weight and Smith machine squat exercises.

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Comparison of the two most commonly used gold-standard velocity monitoring devices (GymAware and T-Force) to assess lifting velocity during the free-weight barbell back squat exercise

Proceedings of the Institution of Mechanical Engineers Part P Journal of Sports Engineering and Technology ◽

10.1177/17543371211029614 ◽

2021 ◽

pp. 175433712110296

Author(s):

Danica Janicijevic ◽

Amador García-Ramos ◽

Juan Luis Lamas-Cepero ◽

Felipe García-Pinillos ◽

Aitor Marcos-Blanco ◽

...

Keyword(s):

Systematic Bias ◽

Maximal Velocity ◽

Force Coefficient ◽

Mean Velocity ◽

Back Squat ◽

Free Weight ◽

Squat Exercise ◽

The Right ◽

Monitoring Devices ◽

Overall Reliability

This study aimed to compare the reliability and agreement of mean velocity (MV) and maximal velocity (Vmax) between the two velocity monitoring devices (GymAware vs T-Force) most commonly used in the scientific literature. Twenty resistance-trained males completed two testing sessions. The free-weight barbell back squat one-repetition maximum (1RM) was determined in the first session (125.0 ± 24.2 kg; mean ± standard deviation). The second session consisted of two blocks of 16 repetitions (six repetitions at 45% 1RM and 65% 1RM, and four repetitions at 85% 1RM). Half of the repetitions were performed with the GymAware on the left side of the barbell and the other half of the repetitions were performed on the right side of the barbell (opposite placement for the T-Force). MV and Vmax were recorded simultaneously with the GymAware and T-Force. The overall reliability, which was calculated pooling together the data of three loads, did not differ between the T-Force (coefficient of variation (CV) = 5.28 ± 1.79%) and GymAware (CV = 5.79 ± 2.26%) (CVratio = 1.10), but the reliability was higher for Vmax (CV = 5.08 ± 1.79%) compared to MV (CV = 5.98 ± 2.73%) (CVratio = 1.18). MV was significantly higher for the T-Force ( p < 0.001, Δ = 4.42%), but no significant differences were detected between the devices for Vmax ( p = 0.455, Δ = 0.22%). These results support the use of both the GymAware and T-Force as gold-standards in studies designed to validate other velocity monitoring devices. However, systematic bias, albeit rather constant, exists for the magnitude of MV between the two devices.

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The Reliability and Validity of Current Technologies for Measuring Barbell Velocity in the Free-Weight Back Squat and Power Clean

Sports ◽

10.3390/sports8070094 ◽

2020 ◽

Vol 8 (7) ◽

pp. 94

Author(s):

Steve W. Thompson ◽

David Rogerson ◽

Harry F. Dorrell ◽

Alan Ruddock ◽

Andrew Barnes

Keyword(s):

Peak Velocity ◽

Reliability And Validity ◽

Systematic Bias ◽

Mean Velocity ◽

Validity Data ◽

Back Squat ◽

Free Weight ◽

Device Reliability ◽

Measurement Units ◽

Power Clean

This study investigated the inter-day and intra-device reliability, and criterion validity of six devices for measuring barbell velocity in the free-weight back squat and power clean. In total, 10 competitive weightlifters completed an initial one repetition maximum (1RM) assessment followed by three load-velocity profiles (40–100% 1RM) in both exercises on four separate occasions. Mean and peak velocity was measured simultaneously on each device and compared to 3D motion capture for all repetitions. Reliability was assessed via coefficient of variation (CV) and typical error (TE). Least products regression (LPR) (R2) and limits of agreement (LOA) assessed the validity of the devices. The Gymaware was the most reliable for both exercises (CV < 10%; TE < 0.11 m·s−1, except 100% 1RM (mean velocity) and 90‒100% 1RM (peak velocity)), with MyLift and PUSH following a similar trend. Poorer reliability was observed for Beast Sensor and Bar Sensei (CV = 5.1–119.9%; TE = 0.08–0.48 m·s−1). The Gymaware was the most valid device, with small systematic bias and no proportional or fixed bias evident across both exercises (R2 > 0.42–0.99 LOA = −0.03–0.03 m·s−1). Comparable validity data was observed for MyLift in the back squat. Both PUSH devices produced some fixed and proportional bias, with Beast Sensor and Bar Sensei being the least valid devices across both exercises (R2 > 0.00–0.96, LOA = −0.36–0.46 m·s−1). Linear position transducers and smartphone applications could be used to obtain velocity-based data, with inertial measurement units demonstrating poorer reliability and validity.

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Estimation of Relative Load From Bar Velocity in the Full Back Squat Exercise

Sports Medicine International Open ◽

10.1055/s-0043-102933 ◽

2017 ◽

Vol 01 (02) ◽

pp. E80-E88 ◽

Cited By ~ 49

Author(s):

Luis Sánchez-Medina ◽

Jesús Pallarés ◽

Carlos Pérez ◽

Ricardo Morán-Navarro ◽

Juan González-Badillo

Keyword(s):

Relative Strength ◽

Loading Test ◽

Mean Velocity ◽

Relative Load ◽

Back Squat ◽

Training Approach ◽

Velocity Relationship ◽

Squat Exercise ◽

Close Relationship ◽

Bar Velocity

AbstractThe use of bar velocity to estimate relative load in the back squat exercise was examined. 80 strength-trained men performed a progressive loading test to determine their one-repetition maximum (1RM) and load-velocity relationship. Mean (MV), mean propulsive (MPV) and peak (PV) velocity measures of the concentric phase were analyzed. Both MV and MPV showed a very close relationship to %1RM (R2=0.96), whereas a weaker association (R2=0.79) and larger SEE (0.14 vs. 0.06 m·s−1) were found for PV. Prediction equations to estimate load from velocity were obtained. When dividing the sample into 3 groups of different relative strength (1RM/body mass), no differences were found between groups for the MPV attained against each %1RM. MV attained with the 1RM was 0.32±0.03 m·s−1. The propulsive phase accounted for ~82% of concentric duration at 40% 1RM, and progressively increased until reaching 100% at 1RM. Provided that repetitions are performed at maximal intended velocity, a good estimation of load (%1RM) can be obtained from mean velocity as soon as the first repetition is completed. This finding provides an alternative to the often demanding, time-consuming and interfering 1RM or nRM tests and allows implementing a velocity-based resistance training approach.

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The effects of a high-intensity free-weight back-squat exercise protocol on postural stability in resistance-trained males

Journal of Sports Sciences ◽

10.1080/02640414.2014.934709 ◽

2014 ◽

Vol 33 (2) ◽

pp. 211-218 ◽

Cited By ~ 3

Author(s):

R.M. Thiele ◽

E.C. Conchola ◽

T.B. Palmer ◽

J.M. DeFreitas ◽

B.J. Thompson

Keyword(s):

High Intensity ◽

Postural Stability ◽

Exercise Protocol ◽

Back Squat ◽

Free Weight ◽

Squat Exercise

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Validity and Reliability of the PUSH Wearable Device to Measure Movement Velocity During the Back Squat Exercise

The Journal of Strength and Conditioning Research ◽

10.1519/jsc.0000000000001284 ◽

2016 ◽

Vol 30 (7) ◽

pp. 1968-1974 ◽

Cited By ~ 43

Author(s):

Carlos Balsalobre-Fernández ◽

Matt Kuzdub ◽

Pedro Poveda-Ortiz ◽

Juan del Campo-Vecino

Keyword(s):

Wearable Device ◽

Validity And Reliability ◽

Movement Velocity ◽

Back Squat ◽

Squat Exercise

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Reliability and concurrent validity of a functional electromechanical dynamometer device for the assessment of movement velocity

Proceedings of the Institution of Mechanical Engineers Part P Journal of Sports Engineering and Technology ◽

10.1177/1754337120984883 ◽

2021 ◽

pp. 175433712098488

Author(s):

Ángela Rodriguez-Perea ◽

Daniel Jerez-Mayorga ◽

Amador García-Ramos ◽

Dario Martínez-García ◽

Luis J Chirosa Ríos

Keyword(s):

Concurrent Validity ◽

Reliability And Validity ◽

Random Errors ◽

Range Of Movement ◽

Mean Velocity ◽

Movement Velocity ◽

Paired Samples ◽

Linear Movement ◽

Standard Error Of Measurement ◽

Acceptable Reliability

The aims of the study were (i) to determine the reliability and concurrent validity of a functional electromechanical dynamometer (FEMD) to measure different isokinetic velocities, and (ii) to identify the real range of isokinetic velocity reached by FEMD for different prescribed velocities. Mean velocities were collected simultaneously with FEMD and a linear velocity transducer (LVT) in two sessions that were identical, consisting of 15 trials at five isokinetic velocities (0.40, 0.60, 0.80, 1.00, and 1.20 m·s−1) over a range of movement of 40 cm. The results obtained using each method were compared using Paired samples t-tests, Bland-Altman plots and the Pearson’s product–moment correlation coefficient, while the reliability was determined using the standard error of measurement and coefficient of variation (CV). The results indicate that the mean velocity values collected with FEMD and LVT were practically perfect correlations ( r > 0.99) with low random errors (<0.06 m·s−1), while mean velocity values were systematically higher for FEMD ( p < 0.05). FEMD provided a high or acceptable reliability for mean velocity (CV ≤ 0.24%), time to reach the isokinetic velocity (CV range = 1.68%–9.70%) and time spent at the isokinetic velocity (CV range = 0.53%–8.94%). These results suggest that FEMD offers valid and reliable measurements of mean velocity during a fixed linear movement, as well as a consistent duration of the isokinetic phase. FEMD could be an appropriate device to evaluate movement velocity during linear movements. More studies are needed to confirm the reliability and validity of FEMD to measure different velocity metrics during more complex functional exercises.

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