Variable, but not free‐weight, resistance back squat exercise potentiates jump performance following a comprehensive task‐specific warm‐up

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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Chain-loaded variable resistance warm-up improves free-weight maximal back squat performance

European Journal of Sport Science ◽

10.1080/17461391.2016.1199740 ◽

2016 ◽

Vol 16 (8) ◽

pp. 932-939 ◽

Cited By ~ 3

Author(s):

Minas A. Mina ◽

Anthony J. Blazevich ◽

Giannis Giakas ◽

Laurent B. Seitz ◽

Anthony D. Kay

Keyword(s):

Warm Up ◽

Variable Resistance ◽

Back Squat ◽

Free Weight

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Acute Effects of Elastic Bands During the Free-weight Barbell Back Squat Exercise on Velocity, Power, and Force Production

The Journal of Strength and Conditioning Research ◽

10.1519/jsc.0b013e3181db25de ◽

2010 ◽

Vol 24 (11) ◽

pp. 2944-2954 ◽

Cited By ~ 24

Author(s):

Mark W Stevenson ◽

Joseph M Warpeha ◽

Cal C Dietz ◽

Russell M Giveans ◽

Arthur G Erdman

Keyword(s):

Force Production ◽

Acute Effects ◽

Back Squat ◽

Free Weight ◽

Squat Exercise ◽

Elastic Bands

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Post-Activation Potentiation on Squat Jump Following Two Different Protocols: Traditional vs. Inertial Flywheel

Journal of Human Kinetics ◽

10.2478/hukin-2019-0017 ◽

2019 ◽

Vol 69 (1) ◽

pp. 271-281 ◽

Cited By ~ 2

Author(s):

Rafael Timon ◽

Silvia Allemano ◽

Marta Camacho-Cardeñosa ◽

Alba Camacho-Cardeñosa ◽

Ismael Martinez-Guardado ◽

...

Keyword(s):

Repeated Measures ◽

Rest Interval ◽

Significant Interaction Effect ◽

Jump Performance ◽

Physically Active ◽

Squat Jump ◽

Warm Up ◽

Squat Exercise ◽

Eccentric Actions ◽

Effect Time

Abstract Post‐activation potentiation (PAP) has been defined as a major enhancement of muscular performance following a preload stimulus. The eccentric actions seem to cause a potentiating effect on subsequent explosive exercises. The aim of this study was to determine whether a protocol of squat exercise using an inertial flywheel could have a potentiating effect on jump performance. Sixteen physically active volunteers participated in the study (age: 21.8 ± 2.7 years; body mass index: 23.6 ± 3). All participants completed two different protocols on separate days: a Traditional Protocol (using a half squat with a guided barbell) and an Inertial Flywheel Protocol (using a half squat with an inertial flywheel). Both protocols were similar and consisted of 3 x 6 reps at the load that maximized power, with a 3‐minute rest interval between sets. The squat jump (SJ) was measured by a contact platform at baseline, and four, eight and twelve minutes after the PAP stimulus. A two‐way ANOVA with repeated measures was performed to analyze significant differences over time. There were significant increases of SJ height (p = 0.004, d = 0.665), velocity (p = 0.003, d = 0.688) and power (p = 0.004, d = 0.682) from baseline after the inertial flywheel protocol. A significant interaction effect (time x protocol) was observed, showing that the inertial flywheel protocol had a potentiating effect on the jump performance compared to the traditional protocol, more specifically at 4 and 8 minutes after the PAP stimulus. In conclusion, the inertial flywheel protocol showed a potentiating effect on the squat jump performance, thus this pre‐ conditioning activity could be useful during the warm‐up before the competition.

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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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Vision Based System for “Free-Weight Back Squat” Angle Assessment

Volume 5 - 2020, Issue 9 - September - International Journal of Innovative Science and Research Technology ◽

10.38124/ijisrt20jul141 ◽

2020 ◽

Vol 5 (7) ◽

pp. 162-165

Author(s):

Tharindu Dananjana Silva ◽

B.G.D.A. Madhusanka ◽

H.D.N.S. Priyankara

Keyword(s):

Image Processing ◽

Mobile Application ◽

Side View ◽

Technical Errors ◽

Back Squat ◽

Free Weight ◽

Key Points ◽

Squat Exercise ◽

Correct Technique ◽

Ultimate Purpose

This project is focused on analyzes squat performing video through image processing by considering key points taken from front and side view. There are conditions to check the performance of squat correct or not. If the Squat is correct, three angles are analyzed reference to five positions. The OpenCV is used to identify the five positions. Also, the Vector function is used to determine the reference angles by using the Cosine rule. These angles are calculated at the knee, waist, and ankle. All these angles are calculated on the free-weight back squat exercise. The ultimate purpose of this project is to minimize injuries that occur due to technical errors because most of the armature players get injured due to the difficulty in posing of correct technique. The mobile application is developed to identify user mistakes and can get instructions.

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The investigation of relationships among sprint and jump performance with velocity parameters during propulsive phase of full back squat exercise

Turkish Journal of Sport and Exercise ◽

10.15314/tjse.201439612 ◽

2014 ◽

Vol 16 (3) ◽

pp. 36-36

Author(s):

Ibrahim CAN ◽

Hamit CIHAN ◽

Erdal ARI

Keyword(s):

Jump Performance ◽

Back Squat ◽

Squat Exercise

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Joint-Level Analyses of the Back Squat With and Without Intraset Rest

International Journal of Sports Physiology and Performance ◽

10.1123/ijspp.2018-0662 ◽

2019 ◽

Vol 14 (5) ◽

pp. 583-589 ◽

Cited By ~ 1

Author(s):

Jason D. Stone ◽

Adam C. King ◽

Shiho Goto ◽

John D. Mata ◽

Joseph Hannon ◽

...

Keyword(s):

Sagittal Plane ◽

Movement Pattern ◽

Joint Angles ◽

Mean Power ◽

Joint Power ◽

Joint Level ◽

Back Squat ◽

Squat Exercise ◽

Limb Kinematics ◽

Plane Joint

Purpose: To provide a joint-level analysis of traditional (TS) and cluster (CS) set structure during the back-squat exercise. Methods: Eight men (24 [3] y, 177.3 [7.9] cm, 82.7 [11.0] kg, 11.9 [3.5] % body fat, and 150.3 [23.0] kg 1-repetition maximum [1RM]) performed the back-squat exercise (80%1RM) using TS (4 × 6, 2-min interset rest) and CS (4 × [2 × 3], 30-s intraset rest, 90-s interset rest), randomly. Lower-limb kinematics were collected by motion capture, as well as kinetic data by bilateral force platforms. Results: CS attenuated the loss in mean power (TS −21.6% [3.9%]; CS −12.4% [7.5%]; P = .042), although no differences in gross movement pattern (sagittal-plane joint angles) within and between conditions were observed (P ≥ .05). However, joint power produced at the hip increased from repetition (REP) 1 through REP 6 during TS, while a decrease was noted at the knee. A similar pattern was observed in the CS condition but was limited to the hip. Joint power produced at the hip increased from REP 1 through REP 3 but returned to REP 1 values before a similar increase through REP 6, resulting in differences between conditions (REP 4, P = .018; REP 5, P = .022). Conclusions: Sagittal-plane joint angles did not change in either condition, although CS elicited greater power. Differing joint power contributions (hip and knee) suggest potential central mechanism that may contribute to enhanced power output during CS and warrant further study. Practitioners should consider incorporating CS into training to promote greater power adaptations and to mitigate fatigue.

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Effects of front and back squat techniques on patellofemoral joint kinetics in males

Journal of Biomedical Engineering and Informatics ◽

10.5430/jbei.v2n1p76 ◽

2015 ◽

Vol 2 (1) ◽

pp. 76 ◽

Cited By ~ 1

Author(s):

J Sinclair ◽

S Atkins ◽

N Kudiersky ◽

PJ Taylor ◽

H Vincent

Keyword(s):

Patellofemoral Joint ◽

Pain Syndrome ◽

Current Investigation ◽

Strength And Conditioning ◽

Joint Kinetics ◽

Associated Injury ◽

Back Squat ◽

Squat Exercise ◽

Experienced Male ◽

Joint Load

Purpose: The barbell squat is fundamental in strength and conditioning, with two principal variants; the back and front squat. Unfortunately, the propensity for injury is high particularly at the knee. The aim of the current investigation was examine the influence of front and back squat variations on patellofemoral joint load. Methods: Patellofemoral loads were obtained from thirty-five experienced male participants, who completed both back and front squats at 70% of 1 RM. Differences between squat conditions were examined using Bonferroni adjusted (P = .008) paired t-tests. Results: The results showed that significant differences (P < .008) in patellofemoral load were identified between both conditions with the highest load being experienced during the back squat exercise. Conclusions: Given the proposed relationship between the magnitude of the load experienced by the patellofemoral joint and associated injury pathology, the back squat appears to place lifters at greater risk from injury. Therefore, it may be prudent therefore for lifters who are predisposed to patellofemoral pain syndrome to utilize the front squat in their training.

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