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Velocity- and power-load relationships in the half, parallel and full back squat

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Abstract

This study aimed to compare the load-velocity and load-power relationships of three common variations of the squat exercise. 52 strength-trained males performed a progressive loading test up to the one-repetition maximum (1RM) in the full (F-SQ), parallel (P-SQ) and half (H-SQ) squat, conducted in random order on separate days. Bar velocity and vertical force were measured by means of a linear velocity transducer time-synchronized with a force platform. The relative load that maximized power output (Pmax) was analyzed using three outcome measures: mean concentric (MP), mean propulsive (MPP) and peak power (PP), while also including or excluding body mass in force calculations. 1RM was significantly different between exercises. Load-velocity and load-power relationships were significantly different between the F-SQ, P-SQ and H-SQ variations. Close relationships (R² = 0.92–0.96) between load (%1RM) and bar velocity were found and they were specific for each squat variation, with faster velocities the greater the squat depth. Unlike the F-SQ and P-SQ, no sticking region was observed for the H-SQ when lifting high loads. The Pmax corresponded to a broad load range and was greatly influenced by how force output is calculated (including or excluding body mass) as well as the exact outcome variable used (MP, MPP, PP).

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... Furthermore, it is essential to understand the differences between mechanical power variables when modeling the P max-load for training prescription purposes. For example, regarding this matter, previous research with young trained adults observed that the P max-load is exercise-specific and differs according to the mechanical power variable measured Sánchez-Medina et al., 2014;Soriano et al., 2015Soriano et al., , 2017Martínez-Cava et al., 2019). These differences indicate that it is essential to define beforehand what mechanical power variable will be measured and monitored during the training program (considering the features of the linear encoder) to avoid erroneous decisions regarding training prescription. ...
... We hypothesized that the P max-load in the leg press and chest press would be similar between older women and men (Strand et al., 2019). In addition, we hypothesized that the MP max-load and PP max-load would differ within and between resistance exercises Sánchez-Medina et al., 2014;Martínez-Cava et al., 2019). Finally, we hypothesized that the MP max and PP max in the chest press would explain the MBT performance variance, while the MP max and PP max in the leg press would explain the performance variability in functional field tests for the lower limbs, including standing up from a chair and short-distance walking. ...
... Compared to PP max-load, the MP max-load in the leg press and chest press increased to around 66% and 62% 1RM, respectively. Despite its novelty in older populations, these data also indicate that the P max-load differs between mechanical power variables in older adults, as observed in young adults Sánchez-Medina et al., 2014;Martínez-Cava et al., 2019). Although most studies with older adults analyzed the P max-load using the peak power variable (de Vos et al., 2005;Potiaumpai et al., 2016;Ni and Signorile, 2017;Strand et al., 2019), several authors observed higher reliability using mean values than peak values when conducting a progressive loading test in the leg press with this population (Alcazar et al., 2017). ...
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Identifying the relative loads (%1RM) that maximize power output (P max-load ) in resistance exercises can help design interventions to optimize muscle power in older adults. Moreover, examining the maximal mean power (MP max ) and peak power (PP max ) values (Watts) would allow an understanding of their differences and associations with functionality markers in older adults. Therefore, this research aimed to 1) analyze the load-mean and peak power relationships in the leg press and chest press in older adults, 2) examine the differences between mean P max-load (MP max-load ) and peak P max-load (PP max-load ) within resistance exercises, 3) identify the differences between resistance exercises in MP max-load and PP max-load , and 4) explore the associations between MP max and PP max in the leg press and chest press with functional capacity indicators. Thirty-two older adults (79.3 ± 7.3 years) performed the following tests: medicine ball throw (MBT), five-repetition sit-to-stand (STS), 10-m walking (10 W), and a progressive loading test in the leg press and chest press. Quadratic regressions analyzed 1) the load-mean and peak power relationships and identified the MP max-load , MP max , PP max-load , and PP max in both exercises, 2) the associations between MP max and PP max in the chest press with MBT, and 3) the associations between MP max and PP max in the leg press with STS power and 10W velocity . In the leg press, the MP max-load was ∼66% 1RM, and the PP max-load was ∼62% 1RM, both for women and men ( p > 0.05). In the chest press, the MP max-load was ∼62% 1RM, and the PP max-load was ∼56% 1RM, both for women and men ( p > 0.05). There were differences between MP max-load and PP max-load within exercises ( p < 0.01) and differences between exercises in MP max-load and PP max-load ( p < 0.01). The MP max and PP max in the chest press explained ∼48% and ∼52% of the MBT-1 kg and MBT-3 kg variance, respectively. In the leg press, the MP max and PP max explained ∼59% of STS power variance; however, both variables could not explain the 10W velocity performance ( r 2 ∼ 0.02). This study shows that the P max-load is similar between sexes, is resistance exercise-specific, and varies within exercises depending on the mechanical power variable used in older adults. Furthermore, this research demonstrates the influence of the MBT as an upper-limb power marker in older adults.
... Therefore, bearing in mind the above-mentioned aspects and according to Wilk et al. 4,5 , time under tension might be the most reliable indicator to assess exercise volume in resistance exercise regardless of the number of performed REPs and desired ROM. The effects of the ROM on training outcomes have been widely analyzed [7][8][9][10][11][12][13] . A study by Martínez-Cava et al. 11,12 indicated that the mean velocity achieved against a wide range of loads was significantly higher, with a greater ROM during resistance exercises. ...
... The effects of the ROM on training outcomes have been widely analyzed [7][8][9][10][11][12][13] . A study by Martínez-Cava et al. 11,12 indicated that the mean velocity achieved against a wide range of loads was significantly higher, with a greater ROM during resistance exercises. In regards to the long-term adaptations, Pallarés et al. 13 found that 10 weeks of full ROM back squat exercise produced greater improvements in jump height, as compared to partial ROM in that exercise. ...
... These findings should be taken into account especially when designing research procedures comparing the effectiveness of different ROM in a given exercise on the training outcomes. The results of this type of studies rather indicated a superior effect of the full ROM compared to the partial one on muscle development [10][11][12][13]29 , with some exceptions 8,9 . However, only one of these studies equalized the training volume to the time under tension 8 or load-displacement 10 while the vast majority did so based on the number of Table 3. Differences in performance variables during a standard and cambered barbell bench press. ...
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Abstract The resistance training volume along with the exercise range of motion has a significant impact on the training outcomes. Therefore, this study aimed to examine differences in training volume assessed by a number of performed repetitions, time under tension, and load–displacement as well as peak barbell velocity between the cambered and standard barbell bench press training session. The participants performed 3 sets to muscular failure of bench press exercise with the cambered or standard barbell at 50% of one-repetition maximum (1RM). Eighteen healthy men volunteered for the study (age = 25 ± 2 years; body mass = 92.1 ± 9.9 kg; experience in resistance training 7.3 ± 2.1 years; standard and cambered barbell bench press 1RM > 120% body mass). The t-test indicated a significantly higher mean range of motion for the cambered barbell in comparison to the standard (p
... No entanto, métodos indiretos também possuem limitações relevantes [3]. A medição da velocidade de movimento durante os exercícios resistidos ganhou popularidade no campo da força e condicionamento para evitar as limitações desses métodos, visto que relações quase perfeitas foram encontradas entre a magnitude da carga e a velocidade da barra em muitos exercícios resistidos [7][8][9][10][11]. Neste sentido, equações de regressão generalizadas foram propostas para determinar a carga relativa (% 1RM) e a carga de 1RM [8,12]. ...
... A postura era afastada aproximadamente na largura dos ombros, pés paralelos apoiados no chão ou rodados externamente a um máximo de 15°. A partir dessa posição, os participantes desceram em movimento controlado até que a prega inguinal atingisse (ponto B) o mesmo plano horizontal da borda superior da patela [10,22]. Após uma pausa momentânea (~1,5 s), eles subiram de volta à posição ereta, mantendo uma postura de tronco ereta [23]. ...
... O teste t de uma amostra mostrou medidas antropométricas, força absoluta e relativa bastante semelhantes (p > 0,05) entre nossa amostra e os homens treinados do estudo de Martínez-Cava et al. [10] (Tabela II). Quando comparados com os atletas de beisebol da Divisão I da NCAA do estudo de Spitz et al. [30], houve diferença estatística entre os homens destreinados do nosso estudo e os atletas do estudo mencionado (Tabela II). ...
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Objetivos: Os objetivos deste estudo foram: 1) comparar a relação carga-velocidade estimada pelo método de dois pontos entre homens e mulheres destreinados durante o exercício agachamento paralelo (BS) e 2) comparar o perfil carga-velocidade encontrado em nosso estudo com os perfis de carga-velocidade relatados na literatura científica para indivíduos treinados. Além disso, comparar a velocidade de 1RM medida com a velocidade de 1RM predita pelo método de dois pontos no exercício BS em indivíduos destreinados. Métodos: Setenta e seis indivíduos destreinados (38 homens (22,7 ± 4,4 anos; 174,9 ± 6,8 cm; 76,1 ± 14,9 kg) e 38 mulheres (24,7 ± 4,3 anos; 159,1 ± 6,0 cm; 64,7 ± 13,3 kg) realizaram um teste de uma repetição máxima e um teste progressivo de duas cargas com 20% e 70% 1RM para estimar suas relações carga-velocidade. Resultados: Os principais resultados revelaram que 1) a velocidade média propulsiva e a velocidade média atingida em cada carga relativa foram diferentes entre homens e mulheres (p < 0,05). No entanto, a velocidade de 1RM medida não foi significativamente diferente entre eles. Homens destreinados forneceram uma relação carga-velocidade mais acentuada do que as mulheres. Descobrimos que 2) os indivíduos destreinados de nosso estudo apresentaram um perfil carga-velocidade diferente dos indivíduos treinados dos estudos da literatura científica. Além disso, 3) a velocidade de 1RM medida foi menor do que a velocidade de 1RM predita (p < 0,05). Conclusão: Esses resultados sugerem que a relação carga-velocidade é dependente do sexo e treinamento, e que o método de dois pontos usando 20% e 70% 1RM não seria confiável para estimar a relação carga-velocidade no exercício agachamento paralelo em homens e mulheres destreinados. Palavras-chave: exercício; mensuração da velocidade; força muscular.
... One practical application provided by the VBT is the determination of players' individual L-V relationship, based on the close association between the barbell velocity and the %1RM (21,29,33,49). The L-V relationship ensures that the player trains at the programmed % 1RM in each training set, thus avoiding the meaningful mismatches that might occur when programming is based on the kg-%1RM method and the negative effects related to the traditional nRM approach (12,35,39,44). ...
... Therefore, after familiarization with the correct execution of the exercise, soccer players would benefit from performing the concentric phase as fast as they can. On the other hand, factors like the range of motion (ROM) used (higher MPV as the ROM increases) (29) or the strategy used to transition from the concentric to the eccentric phase (i.e., with or without pause, higher MPV during nonpaused executions) (34) significantly influence the resulted MPV. Hence, if the evaluators do not control these factors, they could not be confident that changes in barbell velocity are because of actual strength changes and not to variations in the technical execution. ...
... For Velocity-Based Resistance Training in Soccer VOLUME 00 | NUMBER 00 | FEBRUARY 2022 a Imposing a momentary pause for 2 seconds between the eccentric and concentric phases (31,34). Bench press and prone bench pull (49); full squat (paused) (29); full squat (nonpaused) (50); deadlift (33); shoulder press (21); pull-ups (51). ...
... Another important application of measuring bar velocity is to determine the range of loads able to maximize power output through the load-power relationship [10,17], defined as the "optimum power zone" [22]. There is evidence supporting the effectiveness of training in the "optimum power zone" to enhance strength performance [22,23]. ...
... However, loads in the range 40-80% (BSQ) and 50-70% 1RM (HBD) did not differ statistically concerning P max (Figure 3). These data strongly support previous studies showing that mechanical power output is quite similar across a range of light-moderate loads in other resistance exercises such as the bench press (20-60% 1RM) [37], bench pull (20-70% 1RM) (37), traditional deadlift (40-80% 1RM) [17], and half-BSQ (25-85% 1RM) [10]. These findings raise some questions about how much attention has been given to determining a single "optimal load" [24,37,38]. ...
... The strong load-velocity relationship in the BSQ performed on the Smith machine [6,10,15] and the traditional deadlift [8,16,17,31] has already been described, and the current study has extended that understanding to their variants (i.e., free-mode BSQ and HBD). Performing the BSQ using the Smith machine equipment limits the horizontal displacement of the bar in lifting, which might enhance the model prediction [13]. ...
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The aim of this study was to analyse the load-velocity and load-power relationships in the free-weight back-squat (BSQ) and hexagonal bar deadlift (HBD) exercises. Twenty-five (n = 25) resistance-trained men (age = 23.7 ± 2.8 years) performed a progressive load test at maximal intended velocity to determine their BSQ and HBD one-repetition maximum (1RM). Mean propulsive velocity (MPV) during the concentric phase of the lift was recorded through a linear encoder. Load-velocity and load-power relationships were analysed by fitting linear regression and the second-order polynomial, respectively, to the data. Maximum strength (1RM), MPV (30–80% 1RM), and power output (30–90% 1RM) were higher for HBD compared to BSQ exercise (p < 0.05). A very strong relationship between MPV and relative intensity was found for both BSQ (R2 = 0.963) and HBD (R2 = 0.967) exercises. The load that maximizes power output (Pmax) was 64.6 ± 2.9% (BSQ) and 59.6 ± 1.1% (HBD) 1RM. There was a range of loads at which power output was not different than Pmax (BSQ: 40–80% 1RM; HBD: 50–70% 1RM). In conclusion, the load-velocity and load-power relationships might assist strength and conditioning coaches to monitor and prescribe exercise intensity in the BSQ and HBD exercises using the velocity-based training approach.
... 18,19 In addition, training effects can be modulated by the range of motion (ROM), defined as the degree of movement that occurs at a specific joint during the execution of an exercise. 20 In daily practice, the ROM can be modified by altering the body posture 21 or grip width, 22,23 using external materials like security bars or wood boards 24,25 or by voluntarily reducing the degree of movement at the beginning or end of the execution. 26,27 Thus, resistance training with no restrictions in the degree of movement is commonly defined as "full ROM," while training using any displacement reduction is considered as "partial ROM." 28 On this matter, the specific ROM influences different biomechanical aspects that affect, among others, the development of force, motor units activation, and dynamic joint stability. ...
... 26,27 Thus, resistance training with no restrictions in the degree of movement is commonly defined as "full ROM," while training using any displacement reduction is considered as "partial ROM." 28 On this matter, the specific ROM influences different biomechanical aspects that affect, among others, the development of force, motor units activation, and dynamic joint stability. 25,29 More specifically, the ROM used in each repetition determines the zone of the force-length relationship on which the stimulus is applied. 30 Thus, providing this stimulus at a longer or shorter muscle length, as well as avoiding specific zones within this force-length relationship (eg, zone of maximal active or passive force), 31 could modulate the neuromuscular and functional adaptations. ...
... Moreover, partial ROM resistance training has been believed to produce greater strength adaptations, since it allows us to lift a higher absolute weight, as a result of evading the critical region of the movement (ie, the sticking region). 25,71 However, this was not supported by the current meta-analysis, with most of the studies reporting greater neuromuscular adaptations after a full ROM training, both in the upper 59,60,62,65 and lower limbs, 56,63,64,67 even using lower absolute loads (ie, kg) (Table 1, Figure 3). The sticking region would be caused by an interaction between the muscle force-length relationship and the external torque. ...
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Background Nowadays, there is a lack of consensus and high controversy about the most effective range of motion (ROM) to minimize the risk of injury and maximize the resistance training adaptations. Objective To conduct a systematic review and meta-analysis of the scientific evidence examining the effects of full and partial ROM resistance training interventions on neuromuscular, functional, and structural adaptations. Methods The original protocol (CRD42020160976) was prospectively registered in the PROSPERO database. Medline, Scopus, and Web of Science databases were searched to identify relevant articles from the earliest record up to and including August 2020. The RoB 2 and GRADE tools were used to judge the level of bias and quality of evidence. Meta-analyses were performed using robust variance estimation with small-sample corrections. Results Sixteen studies were finally included in the systematic review and meta-analyses. Full ROM training produced significantly greater adaptations than partial ROM on muscle strength (ES=0.56, P=0.004) and lower-limb hypertrophy (ES=0.88, P=0.027). Furthermore, although not statistically significant, changes in functional performance were maximized by the full ROM training (ES=0.44, P=0.186). Finally, no significant superiority of either ROM was found to produce changes in muscle thickness, pennation angle, and fascicle length (ES=0.28, P=0.226). Conclusion Full ROM resistance training is more effective than partial ROM to maximize muscle strength and lower-limb muscle hypertrophy. Likewise, functional performance appears to be favored by the use of full ROM exercises. On the other hand, there are no large differences between the full and partial ROM interventions to generate changes in muscle architecture.
... In the past years, the velocity-based training (VBT) approach (i.e., monitoring the barbell velocity) has been shown as a highly effective and reliable methodology for training prescription and load monitoring during resistance training programs (3,15,20,26). Among other advantages, VBT allows to accurately determinate the relative load (%1RM) the lifter is using by measuring the first repetition of a set (6,10,17,18,29) and the objective assessment of the neuromuscular fatigue that is being incurred during the set, by monitoring the velocity loss (8,28). Thus, VBT allows coaches to accurately determine the strength level of the lifter and precisely program the training stimulus daily. ...
... Among the diverse causes, the individual differences in the strength level have been postulated as a possible cause of this large variability (5,8). Nevertheless, these studies used common velocities (provided by a general load-velocity relationship) associated with each %1RM to examine this intersubject variability (8,27 (10), and prone bench pull [PBP] (29), respectively) have been found in these general relationships, the velocity attained to each % 1RM may present relevant variations between individuals up to ;0.15 m·s 21 (10,11,17,18,29). This fact could have generated slight but meaningful differences (;10-12%) in the %1RM used by the individuals of these studies, thus increasing the nRM inconsistency in a biased way (8,27). ...
... This fact could have generated slight but meaningful differences (;10-12%) in the %1RM used by the individuals of these studies, thus increasing the nRM inconsistency in a biased way (8,27). Therefore, it would be necessary to examine the intersubject variability in the nRM by using the actual %1RM (i.e., individual's load-velocity relationship) (17,18), as well as to clarify if the strength level could influence this variability. ...
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Hernández-Belmonte, A, Courel-Ibáñez, J, Conesa-Ros, E, Martínez-Cava, A, and Pallarés, JG. Level of effort: A reliable and practical alternative to the velocity-based approach for monitoring resistance training. J Strength Cond Res XX(X): 000-000, 2021-This study analyzed the potential of the level of effort methodology as an accurate indicator of the programmed relative load (percentage of one-repetition maximum [%1RM]) and intraset volume of the set during resistance training in the bench press, full squat, shoulder press, and prone bench pull exercises, through 3 specific objectives: (a) to examine the intersubject and intrasubject variability in the number of repetitions to failure (nRM) against the actual %1RM lifted (adjusted by the individual velocity), (b) to investigate the relationship between the number of repetitions completed and velocity loss reached, and (c) to study the influence of the subject's strength level on the aforementioned parameters. After determining their individual load-velocity relationships, 30 subjects with low (n = 10), medium (n = 10), and high (n = 10) relative strength levels completed 2 rounds of nRM tests against their 65, 75, 85, and 95% 1RM in the 4 exercises. The velocity of all repetitions was monitored using a linear transducer. Intersubject and intrasubject variability analyses included the 95% confidence intervals (CIs) and the the standard error of measurement (SEM), respectively. Coefficient of determination (R2) was used as the indicator of relationship. nRM showed a limited intersubject (CI ≤ 4 repetitions) and a very low intrasubject (SEM ≤1.9 repetitions) variability for all the strength levels, %1RM, and exercises analyzed. A very close relationship (R2 ≥ 0.97) between the number of repetitions completed and the percentage of velocity loss reached (from 10 to 60%) was found. These findings strengthen the level of effort as a reliable, precise, and practical strategy for programming resistance training.
... 6 Recently, some studies have proposed a slight variation of the traditional SQ technique, by including a momentary pause (∼2 s) between eccentric and concentric phases. 2,7,8 Despite the fact that this pause would increase the measure's reliability (lower within-subject variation), 9 different investigations have found that a large stop between the lengthening (eccentric) and shortening (concentric) phases decreases substantially the subsequent concentric performance. [9][10][11] This fact could be explained by the dissipation of the elastic energy stored in the muscle series' elastic components and the reduction of the reflexively induced neural input and potentiation of the contractile machinery. ...
... 2,3,15 In addition the VBT would allow researchers/coaches to: (1) assess the athlete's maximum strength (1-repetition maximum [1RM]) in the SQ exercise, 2,3 without the need to perform a maximal test or a repetitions to failure test and (2) determine the % 1RM the athlete is using in this exercise by measuring the first repetition of the set. 6,7 Thus, the VBT would ensure that each of the SQ repetitions performed throughout the intervention is executed at the programmed %1RM, therefore avoiding the mismatches that might occur when programming is solely based on the fixed intensity value (in kilograms) measured at the preintervention test. 16,17 Therefore, the present study aimed to analyze the effects of imposing a pause between eccentric and concentric phases in the SQ exercise on neuromuscular and functional adaptations after a longitudinal resistance training intervention. ...
... Interset recoveries ranged from 3 (light loads) to 5 minutes (heavy loads). 2 The heaviest load that each participant could properly lift using a full range of motion, and without external help was considered his 1RM. 7 In addition, T1 and T2 were conducted at the same time of day (09:00-11:00 h) to control the circadian rhythms effects on neuromuscular performance 18 and under similar environmental conditions (21°C-22°C and 53%-62% humidity). A very high test-retest reliability of this testing protocol (intraclass correlation coefficients [ICCs] = .99; ...
Article
Purpose: A variation of the traditional squat (SQ) rebound technique (REBOUND) including a momentary pause ∼2 seconds (PAUSE) between eccentric and concentric phases has been proposed. Although there is a consensus about the lower acute effects on performance of this PAUSE variant compared with traditional REBOUND technique, no information exists about the differences in longitudinal adaptations of these SQ executions. Methods: A total of 26 men were randomly assigned into the PAUSE (n = 13) or REBOUND (n = 13) groups and completed a 10-week velocity-based training using the SQ exercise, only differing in the technique. Neuromuscular adaptations were assessed by the changes in the 1-repetition maximum strength and mean propulsive velocity achieved against the absolute loads (in kilograms) common to pretest and posttest. Functional performance was evaluated by the following tests: countermovement jump, Wingate, and sprint time at 0 to 10, 10 to 20, and 0 to 20 m. Results: Whereas both groups showed significant increases in most of the neuromuscular tests (P < .05), the PAUSE (effect size [ES] = 0.76-1.12) presented greater enhancements than REBOUND (ES = 0.45-0.92). Although not significant, improvements in Wingate and sprint time at 0 to 10 and 0 to 20 m were higher for PAUSE (ES = 0.31-0.46) compared with REBOUND (ES = 0.10-0.29). Conversely, changes on countermovement jump and sprint time at 10 to 20 m were superior for REBOUND (ES = 0.17-0.88) than for PAUSE (ES = 0.09-0.75). Conclusion: Imposing a pause between eccentric and concentric phases in the SQ exercise could be an interesting strategy to increase neuromuscular and functional adaptations in sport actions that mainly depend on concentric contractions. Moreover, sport abilities highly dependent on the stretch-shortening cycle could benefit from the REBOUND or a combination of the 2 techniques.
... The squat is one of the closed kinetic chain exercises [1][2][3]. The squat process involves more than 200 muscles and demands multi-joint coordination [2,4]. ...
... The squat is one of the closed kinetic chain exercises [1][2][3]. The squat process involves more than 200 muscles and demands multi-joint coordination [2,4]. The squat is widely conducted during resistance training, which could increase lower limb strength, prevent sports injuries, and improve sports performance [5][6][7][8][9]. ...
... Practice of squats in a correct manner will not cause injuries [2], but the incorrect squatting technique and overload will increase the risk of injuries [4,12]. Bodyweight and barbell squats are common methods used during squatting practice [5,7]. ...
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Background: Females with different practice experience may show different body postures and movement patterns while squatting in different depths, which may lead to changes of biomechanical loadings and increase the risks of injuries. Methods: Sixteen novice female participants without squat training experience participated in this study. A 3D motion capture system was used to collect the marker trajectory and ground reaction force data during bodyweight squatting in different depths. The participants' kinematic data and joint moment were calculated using OpenSim's inverse kinematics and inverse dynamics algorithm. In this study, authors adapted a model especially developed for squatting and customized the knee joint with extra Degree-of-Freedom (DoF) in the coronal and horizontal plane with adduction/abduction and internal/external rotation. A paired-sample t-test was used to analyze the difference of joint range of motions (ROM) and peak moments between full-squat (F-SQ) and half-squat (H-SQ). One-Dimensional Statistical Parametric Mapping (SPM1D) is used to analyze the difference of joint angle and moment between the process of squatting F-SQ and H-SQ. Results: (1) Compared with H-SQ, F-SQ showed larger ROM in sagittal, coronal, and transverse planes (p < 0.05). (2) SPM1D found that the difference in joint angles and joint moments between F-SQ and H-SQ was mainly concentrated in the mid-stance during squatting, which suggested the difference is greatly pronounced during deeper squat. (3) Peak hip extension moment, knee extension moment, hip adduction moment, and plantar flexion moment of F-SQ were significantly higher than H-SQ (p < 0.05). (4) Difference of hip and knee extension moments and rotation moments between the F-SQ and H-SQ were exhibited during descending and ascending. Conclusions: The study found that novice women had larger range of joint motion during the F-SQ than H-SQ group, and knee valgus was observed during squatting to the deepest point. Greater joint moment was found during F-SQ and reached a peak during ascending after squatting to the deepest point. Novice women may have better movement control during H-SQ. The findings may provide implications for the selection of lower limb strength training programs, assist the scientific development of training movements, and provide reference for squat movement correction, thus reducing the risk of injury for novice women in squatting practice.
... To be effectively implemented, VBT requires the athlete to lift the load at maximal intended velocity in order to describe the load-velocity relationship (i.e., the velocity attained along a spectrum of loads) for a given exercise [2,3]. Then, practitioners can determine the load-velocity relationship for a given exercise by regression analysis equations (i.e., load-velocity curve) and precisely estimate the relative intensity (%1RM) associated with the resulting velocity [4][5][6][7]. This information has relevant practical implications, mainly individualizing training prescription and load monitoring on a day-to-day basis using velocity monitoring systems [5,8,9]. ...
... Because the load-velocity relationship varies among exercises, the knowledge of particular equations is indispensable to effectively implement the VBT method. Whereas the load-velocity relationship of exercises such as the bench press [5,[10][11][12], squat [4,6,12] A comprehensive analysis of the velocity-based method in the shoulder press exercise: stability of the load-velocity relationship and sticking region parameters Subjects Forty-eight men (age 22.1 ± 3.5 years, body mass 76.3 ± 8.8 kg, height 175.8 ± 5.9 cm) volunteered to take part in this study. Inclusion criteria were: i) having a relative strength ratio (RSR = 1RM weight lifted/body mass) higher than 0.60 in the SP exercise and ii) no health problems, physical limitations or musculoskeletal injuries that could affect the technical executions. ...
... At that point, the athlete experiences a disproportionately large increase in the difficulty to continue the lift, which may lead to muscle failure and eventually cause an injury [19]. The sticking region can be identified from the velocity-time curve [4,11] by three key parameters: the first peak velocity attained during the lift (V max1 ), the minimum velocity that occurs due to the sticking (V min ) and the second peak barbell velocity indicating that the athletes overcome the critical zone (V max2 ). The identification of the position of these three parameters within the concentric phase of the lift would provide great practical implications for athletes and coaches, for instance, to incorporate strategies such as technical execution modifications (e.g., reduction in the range of motion) or the use of external objects (e.g., elastic bands) to more easily solve this region [19,20]. ...
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The purpose of this study was threefold: i) to analyse the load-velocity relationship of the shoulder press (SP) exercise, ii) to investigate the stability (intra-individual variability) of this load-velocity relationship for athletes with different relative strength levels, and after a 10-week velocity-based resistance training (VBT), and iii) to describe the velocity-time pattern of the SP: first peak velocity [Vmax1], minimum velocity [Vmin], and second peak velocity [Vmax2]. This study involves a cross-sectional (T1, n = 48 subjects with low, medium and high strength levels) and longitudinal (T2, n = 24 subjects randomly selected from T1 sample) design. In T1, subjects completed a progressive loading test up to the 1RM in the SP exercise. The barbell mean, peak and mean propulsive velocities (MV, PV and MPV) were monitored. In T2, subjects repeated the loading test after 10 weeks of VBT. There were very close relationships between the %1RM and velocity attained in the three velocity outcomes (T1, R2 : MV = 0.970; MPV = 0.969; PV = 0.954), being even stronger at the individual level (T1, R2 = 0.973–0.997). The MPV attained at the 1RM (~0.19 m·s-1) was consistent among different strength levels. Despite the fact that 1RM increased ~17.5% after the VBT programme, average MPV along the load-velocity relationship remained unaltered between T1 and T2 (0.69 ± 0.06 vs. 0.70 ± 0.06 m·s-1). Lastly, the three key parameters of the velocity-time curve were detected from loads > 74.9% 1RM at 14.3% (Vmax1), 46.1% (Vmin), and 88.7% (Vmax2) of the concentric phase. These results may serve as a practical guideline to effectively implement the velocity-based method in the SP exercise.
... For this reason, displaying 0.1 as the lowest value while performing a squat exercise could lead to an underestimation of the velocity at both submaximal and maximal loads. In addition, in the squat load-velocity profile, a variation of 0.1 m•s −1 corresponds to a load variation of approximately 10% of 1RM or more [21]. Therefore, displaying a scale with only 0.1 m•s −1 intervals can be misleading in the correct velocity estimation. ...
... The scale ( Figure 1) has a range of numerical values from 0.30 to 1.4 m•s −1 that are consistent with what reported in the literature as the minimum and maximal velocity threshold for the squat exercise [21,22]. Interval values are close to the second decimal point. ...
... First of all because the values shown by the devices are always approximated to the second decimal. Secondly, a variation of the mean velocity of 0.10 m•s −1 corresponds, in the squat, to a variation of load of about 10% 1RM [21,22]. Therefore, a scale with intervals of 0.1 (0.1, 0.2, 0.3, etc.) could actually be misleading in the correct perception of the load to be utilized. ...
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Background: the aim of the study was to develop and validate a specific perception velocity scale for the Back Squat exercise to discriminate the velocity of each repetition during a set. Methods: 31 resistance trained participants completed 3 evaluation sessions, consisting of 3 blinded loads (light, medium, heavy). For each repetition, barbell mean velocity (Vr) was measured with a linear position transducer while perceived velocity (Vp) was reported using the Squat Perception of Velocity (PV) Scale. Results: Pearson correlation coefficients (r) showed very high values for each intensity in the 3 different days (range r = 0.73-0.83) and practically perfect correlation for all loads (range r = 0.97-0.98). The simple linear regression analysis between Vp and Vr revealed values ranging from R2 = 0.53 to R2 = 0.69 in the 3 intensities and values ranging from R2 = 0.95 to R2 = 0.97 considering all loads. The reliability (ICC2.1, SEM) of Vp was tested for light (0.85, 0.03), medium Please do not modify the format of the manuscript (type and size of font, margin size, paragraph spacing, etc.), only what is indicated with comments or highlighted, as it follows the standard style of MDPI. We would appreciate if you could mark all the modifications with the Track Changes tool and thoroughly address all the comments.(0.90, 0.03) and heavy loads (0.86, 0.03) and for all loads (0.99, 0.11). The delta score (ds = Vp - Vr) showed higher accuracy of the PV at heavy loads. Conclusions: these results show that the PV Squat Scale is a valid and reliable tool that can be used to accurately quantify exercise intensity.
... Indeed, this close relationship enables coaches to accurately estimate the individual's current 1-RM performance, and therefore to prescribe, in real time, the training loads during resistance training programs [7,8]. This issue has been studied in men using exercises such as the prone bench pull [12], pull-up [13,14], leg-press [15], hipthrust [16], and a number of variations of the squat (SQ) exercise [9,17,18]. Therefore, in these exercises, intensity can be prescribed on a daily basis by adjusting the absolute load (kg) to match the repetition velocity associated with the %1-RM that is intended for the training session. ...
... These studies were conducted on upper-body exercises (BP, inclined BP, and military press) and showed that the load-velocity relationship was strong and linear (individual R 2 range: 0.987-0.993) in both sexes but the velocity associated with each %1-RM was higher in men compared to women [19][20][21]. Therefore, the general equations previously published for the main exercises, such as BP and SQ [8,9,17,18], may not be suitable for women. As a result, if the training load is prescribed with the same velocity value for both men and women, the training stimulus for men and women would be different. ...
... As another drawback to understanding this topic, previous literature attempting to validate the use of movement velocity to estimate relative load [7][8][9][12][13][14][15][16][17][18][19][20][21] has used methods based on correlation, and these methods cannot, on their own, assess systematic bias [24]. In order to assess the level of agreement between the observed and the predicted data, a comprehensive set of statistics should be used [24,25]. ...
Article
This study aimed to examine the validity of using bar velocity to estimate relative load in squat and bench-press exercises for both young men and women. Twenty-five men and 25 women performed a progressive loading test up to 1-RM in the squat and bench-press exercises, which were repeated after 2-weeks. Relationships between mean propulsive velocity and%1-RM were analysed. A second-order polynomial equation for predicting the corresponding velocity of each percentage of 1-RM was developed for men (validation). This equation was then applied in women (cross-validation). Moreover, a specific equation for women was developed (validation) and was also applied in a sub-sample of women (cross-validation). Close relationships (R2: 0.91–0.95) between bar velocity and relative load were observed in both sexes for squat and bench press. Men’s equation applied to women showed a high level of agreement, although lower bias and higher level of agreement was observed when a sex-specific equation was applied in women, both validation and cross-validation samples. In conclusion, lifting velocity can be used to accurately prescribe the relative load regardless of sex in both upper-body and lower-body exercises, although when estimating load from velocity measures it will be necessary to use the sex-specific equation for each exercise.
... Assuming that each percentage of 1RM ( %1RM) is always associated with a given velocity [10,11], different general load-velocity (LV) equations have been previously developed to estimate the %1RM from the recorded velocity with a sub-maximal load [10,12,13]. However, there are some limitations with this approach as: i) an important inter-subject variability in the LV relationship has been previously reported [14][15][16][17][18], ii) low reliability has been observed for the velocity associated to 1RM (V 1RM ) [16,19,20], and iii) the force-velocity relationship analysis has detected a high inter-subject variability for the intercept of the velocity axis and therefore, for the estimated velocity without external load [21,22]. ...
... This result is coincident with previous studies that found high linearity in the LV when individual regressions were analyzed [14,20,23,24]. It must be pointed out that secondorder polynomial generalized LV equations have been previously reported [10,12,13], although the extremely low values of the quadratic coefficient suggest a quasi-linear profile. Therefore, our data reinforce the observation of linearity in individual LV relationships [14,20,23,24], showing that this profile is preserved after different training programs. ...
Article
This study explored the changes in load-velocity relationship of bench press and parallel squat exercises following two programs differing in the set configuration. A randomized controlled trial was carried out in a sample of 39 physically active individuals. Participants were assigned to rest redistribution set configuration, traditional set configuration, or control groups. Over 5 weeks, the experimental groups completed 10 sessions with the 10 repetitions maximum load of both exercises. Rest redistribution sets consisted in 16 sets of 2 repetitions with 60 s of rest between sets, and 5 min between exercises, whereas traditional sets entailed 4 sets of 8 repetitions with 5 min of rest between sets and exercises. The load-velocity relationships of both exercises were obtained before and after the training period. For bench press, an increase of the velocity axis intercept, and a decrease of the slope at post-test were observed in both rest redistribution (p < 0.001, G = 1.264; p < 0.001; G = 0.997) and traditional set (p = 0.01, G = 0.654; p = 0.001; G = 0.593) groups. For squat, the slope decreased (p < 0.001; G = 0.588) and the velocity axis intercept increased (p < 0.001; G = 0.727) only in the rest redistribution group. These results show that rest redistribution sets were particularly efficient for inducing changes in the load-velocity relationship
... The findings mentioned above are based on the load-velocity relationship observed for exercises such as BP and squat. [15][16][17][18][19][20] The load-velocity relationship describes a mean velocity value associated with a certain %1RM, which is very similar for every individual, regardless of strength levels or changes in performance. 15 This velocity value can be obtained from both linear [21][22][23][24] and polynomial regression models. ...
... 15 This velocity value can be obtained from both linear [21][22][23][24] and polynomial regression models. [15][16][17][18][19][20] As a potential drawback, these general equations assume that the velocity associated with each %1RM is the same for all individuals; however, recent studies have shown a significant interindividual variability in the load-velocity relationship for BP and squat exercises. 25 has subsequently been shown that individual load-velocity relationships may provide more accurate predictions of %1RM than general equations. ...
Article
Purpose: This study aimed (1) to analyze the interindividual variability in the maximal number of repetitions (MNR) performed against a given relative load (percentage of 1-repetition maximum [%1RM]) and (2) to examine the relationship between the velocity loss (VL) magnitude and the percentage of completed repetitions with regard to the MNR (%Rep), when the %1RM is based on individual load-velocity relationships. Methods: Following an assessment of 1RM strength and individual load-velocity relationships, 14 resistance-trained men completed 5 MNR tests against loads of 50%, 60%, 70%, 80%, and 90% 1RM in the Smith machine bench-press exercise. The relative loads were determined from the individual load-velocity relationship. Results: Individual relationships between load and velocity displayed coefficients of determination (R2) ranging from .986 to .998. The MNR showed an interindividual coefficient of variation ranging from 8.6% to 33.1%, increasing as the %1RM increased. The relationship between %Rep and the magnitude of VL showed a general R2 of .92 to .94 between 50% and 80% 1RM, which decreased to .80 for 90% 1RM. The mean individual R2 values were between .97 and .99 for all loading conditions. The %Rep when a given percentage of VL was reached showed interindividual coefficient of variation values ranging from 5% to 20%, decreasing as the %Rep increased in each load condition. Conclusions: Setting a number of repetitions had acceptable interindividual variability, with moderate relative loads being adjusted based on the individual load-velocity relationship. However, to provide a more homogeneous level of effort between athletes, the VL approach should be considered, mainly when using individual VL-%Rep relationships.
... Therefore, if bar velocity can be used to predict the intensity employed in the DL exercise is still unclear. Notably, previous literature analyzing load-velocity relationship in DL (Lake et al., 2017;Ruf et al., 2018) examined a small sample size (n = 11-12) compared to those examined in other exercises (sample size of approximately 50 subjects) (González-Badillo and Sánchez-Medina, 2010;Loturco et al., 2017;Martínez-Cava et al., 2018;Sánchez-Medina et al., 2014;Sánchez-Moreno et al., 2017). It therefore seemed pertinent to undertake a detailed analysis of the load-velocity relationship of the DL exercise in a larger sample of strength-trained men in order to confirm the possibility of using bar velocity to estimate loading magnitude (%1RM), as well as to provide normative data for this population. ...
... Moreover, the velocity of 1RM for DL was 0.33 ± 0.06 mꞏs-1, which was similar to the velocities previously reported for 1RM (⁓0.30 mꞏs -1 ) in other lower limb exercises such as full, parallel and half squat (Martínez-Cava et al., 2018). However, these values were faster than the previously reported (⁓0.14 mꞏs -1 ) by Helms et al. (2017). ...
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The aim of this study was to analyze the relationship between movement velocity and relative load (%1RM) in the deadlift exercise. Fifty men (age = 23.8 ± 3.6 years, body mass = 78.2 ± 8.3 kg, height = 1.78 ± 0.06 m) performed a first evaluation (T1) consisting of a one-repetition maximum (1RM) test. Forty-two subjects performed a second evaluation (T2) after 6 weeks. Mean (MV), mean propulsive (MPV) and peak (PV) velocity measures of the concentric phase were analyzed. Load-velocity relationships were studied by fitting first order equations to the data using loads from 30-100% of 1RM. A comprehensive set of statistics for assessing bias and level of agreement to estimate the 1RM value from the different models was used. Stability of these relationships was assessed using the coefficient of variation (CV) and the intraclass correlation coefficient (ICC). General load-velocity equations provided good adjustments (R2 ~; 0.91-0.93), however individual load-velocity regressions provided better adjustments (R2 ~; 0.97). Individual estimations also showed higher agreement and more regular variation than general equations. Moreover, MPV showed smaller bias than the other velocity parameters (MV and PV). The stability analysis of the load-velocity relationships resulted in ICC values higher than 0.82 and CV lower than 3.0%. Monitoring repetition velocity allows estimation of the %1RM in the deadlift exercise. More accurate predictions of relative load can be obtained when using individualized regression equations instead of general equations.
... Linear position and velocity transducers (LPTs and LVTs) are frequently used to collect mechanical outputs in different types of resistance training exercises [1][2][3][4]. In general, these devices are connected to the barbell to assess bar velocity and bar power [2][3][4][5][6]. ...
... Linear position and velocity transducers (LPTs and LVTs) are frequently used to collect mechanical outputs in different types of resistance training exercises [1][2][3][4]. In general, these devices are connected to the barbell to assess bar velocity and bar power [2][3][4][5][6]. ...
Article
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The aims of this study were to compare the outcomes and provide reference data for a set of barbell mechanical parameters collected via a linear velocity transducer in 126 male sprinters (n=62), rugby (n=32), and soccer players (n=32). Bar-velocity, bar-force, and bar-power outputs were assessed in the jump-squat exercise with jump-squat height determined from bar-peak velocity. The test started at a load of 40% of the athletes’ body mass (BM) and a load of 10% of BM was gradually added until a clear decrement in the bar-power was observed. Comparisons of bar-variables among the three sports were performed using a one-way analysis of variance. Relative measures of bar-velocity, -force, and -power, and jump-squat height were significantly higher in sprinters than in rugby (difference ranging between 5 and 35%) and soccer (difference ranging between 5 and 60%) players across all loads (40-110% of BM). Rugby players exhibited higher absolute bar-power (mean difference = 22%) and bar-force (mean difference = 16%) values than soccer players, but these differences no longer existed when the data were adjusted for BM (mean difference = 2.5%). Sprinters optimized their bar-power production at significantly greater relative loads (% BM) than rugby (mean difference = 22%) and soccer players (mean difference = 25%); nonetheless, all groups generated their maximum bar-power outputs at similar bar-velocities. For the first time, we provided reference values for the jump-squat exercise for three different bar-velocity measures (i.e., mean, mean propulsive-, and peak-velocity) for sprinters, rugby, and soccer players, over a wide range of relative loads. Practitioners can use these reference values to monitor their athletes and compare them with top-level sprinters and team-sport players.
... The spotters and strength coaches were present throughout the procedure of 1-RM testing. The athletes started from an upright position, with the knees and hips fully extended, the stance approximately shoulder-width apart with both feet positioned flat on the floor in parallel or externally rotated to a maximum of 15 • [42]. The bar rested across the back at the level of the acromion. ...
... Stance width and feet position were individually adjusted and carefully replicated on every lift. The bar was required to remain in contact with the back and shoulders at all times [42]. From this position, they were required to descend until making contact with the bench and then perform the concentric phase of the movement in an explosive manner [43,44]. ...
Article
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The aim of the present study was to evaluate the effects of external compression with blood flow restriction on power output and bar velocity changes during the back-squat exercise (SQ). The study included 10 judo athletes (age = 28.4 ± 5.8 years; body mass = 81.3 ± 13.1 kg; SQ one-repetition maximum (1-RM) 152 ± 34 kg; training experience 10.7 ± 2.3 years). Methods: The experiment was performed following a randomized crossover design, where each participant performed three different exercise protocols: (1) control, without external compression (CONT); (2) intermittent external compression with pressure of 100% arterial occlusion pressure (AOP) (EC-100); and (3) intermittent external compression with pressure of 150% AOP (EC-150). To assess the differences between conditions, the participants performed 3 sets of 3 repetitions of the SQ at 70% 1-RM. The differences in peak power output (PP), mean power output (MP), peak bar velocity (PV), and mean bar velocity (MV) between the three conditions were examined using repeated measures two-way ANOVA. Results: The post hoc analysis for the main effect of conditions showed a significant increase in PP (p = 0.03), PV (p = 0.02), MP (p = 0.04), and MV (p = 0.03), for the EC-150, compared to the CONT. Furthermore, a statistically significant increase in PP (p = 0.04), PV (p = 0.03), MP (p = 0.02), and MV (p = 0.01) were observed for the EC-150 compared to EC-100. There were no significant changes in PP, PV, MP, and MV, between EC-100 and CONT conditions. Conclusion: The results indicate that the use of extremely high-pressure external compression (150% AOP) during high-loaded (70% 1-RM) lower limb resistance exercise elicits an acute increase in power output and bar velocity.
... Data from absolute loads common to both Pre and Post tests are shown. Velocity data obtained from a linear velocity transducer sampling bar velocity at 1000 Hz find that the obtained 1RMs are reached at a faster mean velocity than that of each exercise's own 1RM velocity (V 1RM ) [42], which is comprised within a small velocity range: V 1RM ≤ 0.20 m s −1 for bench press [42,54], V 1RM ≤ 0.35 m s −1 for squat [52,55], V 1RM ≤ 0.50 m s −1 for prone bench pull [54,56], V 1RM ≤ 0.90 m s −1 for the power clean [57], etc. This lack of accuracy in the determination of 1RM results in a 1RM reference value which is lower than the real or true value. ...
... To the best of our knowledge, the best way that currently exists to solve these problems resides in the use and monitoring of movement velocity during RT for determining both the relative load used and the degree of effort undertaken [5,9,42,65]. In this regard, very close relationships between movement velocity and relative load (%1RM) have been found for exercises such as the bench press [42,[70][71][72][73][74][75], prone bench pull [54,76], squat [52,55,72], deadlift [58,77], pull-up [78,79], leg press [43] and hip thrust [80], which makes it possible to determine with considerable precision the %1RM that is being used as soon as the first repetition of a set is performed with maximal intended velocity [42]. This is based on the finding that each percentage of the 1RM has its own corresponding mean velocity, and the velocity values associated with each percentage of 1RM have been found to be very stable and reliable, regardless of the subjects' performance level or the change in strength performance after a training period [42,52,54,58,78]. ...
Article
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For more than a century, many concepts and several theories and principles pertaining to the goals, organization, methodology and evaluation of the effects of resistance training (RT) have been developed and discussed between coaches and scientists. This cumulative body of knowledge and practices has contributed substantially to the evolution of RT methodology. However, a detailed and rigorous examination of the existing literature reveals many inconsistencies that, unless resolved, could seriously hinder further progress in our field. The purpose of this review is to constructively expose, analyze and discuss a set of anomalies present in the current RT methodology, including: (a) the often inappropriate and misleading terminology used, (b) the need to clarify the aims of RT, (c) the very concept of maximal strength, (d) the control and monitoring of the resistance exercise dose, (e) the existing programming models and (f) the evaluation of training effects. A thorough and unbiased examination of these deficiencies could well lead to the adoption of a revised paradigm for RT. This new paradigm must guarantee a precise knowledge of the loads being applied, the effort they involve and their effects. To the best of our knowledge, currently this can only be achieved by monitoring repetition velocity during training. The main contribution of a velocity-based RT approach is that it provides the necessary information to know the actual training loads that induce a specific effect in each athlete. The correct adoption of this revised paradigm will provide coaches and strength and conditioning professionals with accurate and objective information concerning the applied load (relative load, level of effort and training effect). This knowledge is essential to make rational and informed decisions and to improve the training methodology itself.
... Velocity-based training (VBT) is a novel and practical RT method proposed to rapidly monitor and prescribe relative loads (11,36). It has been demonstrated that the velocity attained during the concentric phase can be used to precisely determine the RT intensity because of the close relationships observed between %1RM and mean propulsive velocity (MPV) in multiple exercises (e.g., bench press, full squat [SQ], parallel squat, and half squat exercises; R 2 $ 0.92 in all exercises) (11,22,37). Therefore, by monitoring repetition velocity, it is possible to determine in real time and with great accuracy the %1RM being used and adjust the load according to the individual changes in strength that usually occur during a RT program. ...
... Changes in selected performance variables from pre-training to post-training for each velocity-based training group.* † using a relative value (i.e., % 1RM) obtained at pre-training or mid-training measurements(3,12,22,27,(33)(34)(35)38,39). However, it is important to highlight that the 1RM value usually fluctuates on a daily basis, especially during strength training interventions ...
Article
Riscart-López, J, Rendeiro-Pinho, G, Mil-Homens, P, Costa, RS-d, Loturco, I, Pareja-Blanco, F, and León-Prados, JA. Effects of Four different velocity-based training programming models on strength gains and physical performance. J Strength Cond Res XX(X): 000-000, 2020-The aim of this study was to compare the effects of 4 velocity-based training (VBT) programming models (linear programming [LP], undulating programming [UP], reverse programming [RP], and constant programming [CP]) on the physical performance of moderately strength-trained men. Forty-three young (age: 22.9 ± 4.8 years; body mass [BM]: 71.7 ± 7.6; full squat [SQ] relative strength 1.32 ± 0.29) subjects were randomly assigned to LP (gradually increase training intensity and decrease volume), UP (volume and intensity increase or decrease repeatedly), RP (gradually increases volume and decrease intensity), and CP (maintains constant volume and intensity) groups and followed an 8-week VBT intervention using the SQ exercise and monitoring movement velocity for every repetition. All groups trained with similar relative average intensity (67.5% 1 repetition maximum [1RM]), magnitude of velocity loss within the set (20%), number of sets (3), and interset recoveries (4 minutes) throughout the training program. Pre-training and post-training measurements included predicted SQ (1RM), average velocity attained for all loads common to pre-tests and post-tests (AV), average velocity for those loads that were moved faster (AV > 1) and slower (AV < 1) than 1 m·s-1 at pre-tests, countermovement jump height (CMJ), and 20-m sprint time (T20). No significant group × time interactions were observed for any of the variables analyzed. All groups obtained similar increases (shown in effect size values) in 1RM strength (LP: 0.88; UP: 0.54; RP: 0.62; CP: 0.51), velocity-load-related variables (LP: 0.74-4.15; UP: 0.46-5.04; RP: 0.36-3.71; CP: 0.74-3.23), CMJ height (LP: 0.35; UP: 0.53; RP: 0.49; CP: 0.34), and sprint performance (LP: 0.34; UP: 0.35; RP: 0.32; CP: 0.30). These results suggest that different VBT programming models induced similar physical performance gains in moderately strength-trained subjects.
... To be effectively implemented, VBT requires the athlete to lift the load at maximal intended velocity and the use of reliable equipment to measure the bar velocity (Courel-Ibáñez et al., 2019). Because of the very high relationship between load and velocity during resistance training exercises along a wide load spectrum Sánchez-Medina et al., 2014;Martinez-Cava et al., 2019) and its low variability on a day-to-day basis (Banyard et al., 2018), one can determine the load-velocity relationship for a given exercise by regression analysis equations (i.e., load-velocity curve) and precisely estimate the load magnitude (%1RM) associated with the resulting velocity. In addition to the velocity, the mechanical power output has been conventionally used as a monitoring measurement in resistance training (Baker et al., 2005). ...
... Because the load-velocity relationship varies among each exercise, the knowledge of describing each particular equation along the entire load spectrum is indispensable to successfully implement the VBT Martinez-Cava et al., 2019;Sánchez-Medina et al., 2014). In this sense, the information on the load-velocity relationship for the deadlift exercise is limited. ...
Article
Velocity-based training (VBT) is gaining popularity in strength and conditioning due to multiple practical advantages for auto-regulating and individualizing training volume and load on a day-to-day basis. Because the load-velocity relationship varies among exercises, the knowledge of particular equations is indispensable to effectively implement the VBT. The aim of this study was to determine the complete load- and power-velocity profile of the deadlift exercise to provide practical equations and normative values for resistance training coaches and practitioners. Twenty strength-trained men performed a progressive loading test at maximal intended velocity to determine their one-repetition maximum (1RM). Mean (MV), mean propulsive (MPV) and peak velocity (PV) were measured during the concentric phase. Both MV and MPV showed a very close relationship to %1RM (R² = 0.971 and R² = 0.963) with a low error of estimation (SEE = 0.08 and 0.09 m·s⁻¹), which was maintained throughout the wide breadth of velocities. PV showed the poorest results (R² = 0.958, SEE = 0.15 m·s⁻¹). MV attained with the 1RM was 0.24±0.03 m·s⁻¹ and consistent between participants with different relative strengths. The load that maximized the power output was identified at ∼60% 1RM. In contrast to what was observed in velocity, power outcomes showed poor predictive capacity to estimate %1RM. Hence, the use of velocity-based equations is advisable to monitor athletes’ performance and adjust the training load in the deadlift exercise. This finding provides an alternative to the demanding, time-consuming and interfering 1RM tests, and allows the use of the deadlift exercise following the VBT principles.
... In fact, since strong correlation has been shown between execution velocity and 1RM (García-Ramos, Pestaña-Melero et al., 2018;Muñoz-López et al., 2017;Pérez-Castilla et al., 2020), the VBT monitoring allows the creation of individualised velocity profile (Alcazar et al., 2017;Banyard et al., 2018), as well as the degree of fatigue (García-Ramos, Torrejón et al., 2018;Haff & Nimphius, 2012;Sánchez-Medina & González-Badillo, 2011). Hence, VBT facilitates the prescription of personalised velocity training zones and the knowledge of the athlete's physiological state (Conceição et al., 2016;González-Badillo et al., 2015;González-Badillo & Sánchez-Medina, 2010) in a robust, non-invasive, and highly sensitive way (González-Badillo & Sánchez-Medina, 2010;Martínez-Cava et al., 2019;Morán-Navarro et al., 2019;Sánchez-Medina & González-Badillo, 2011;Sánchez-Medina et al., 2017). ...
... In the field of VBT, TEM and SEM values of the maximum concentric velocity of 0.07-0.10 m/s can affect the 1RM values by 5% (González-Badillo & Sánchez-Medina, 2010;Martínez-Cava et al., 2019;Sánchez-Medina & González-Badillo, 2011;Sánchez-Medina et al., 2017). All of these values can help standardise the analysis of the results. ...
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This systematic review aimed to summarise and analyse the evidence on the reliability and validity of linear tranducers (LTs) in exercises of different nature and different modes of execution. This systematic review was carried out under PRISMA guidelines, and was carried out using three databases (PubMed, Web of Sciences, and Scopus). Of the 351 initially found, 21 were included in the qualitative synthesis. The results reflected that linear position transducers (LPTs) were valid and reliable in monitoring movement velocity in non-plyometric exercises. However, precision and reliability were lower in execution protocols without isometric phase and in the execution of exercises in multiple planes of movement, with greater measurement errors at higher sampling frequencies. On the other hand, linear velocity transducers (LVTs) proved to be valid and reliable in measuring velocity during plyometric and non-plyometric exercises performed on the Smith machine, with less variation in measurement in the latter. Finally, the use of peak values is recommended, since they are less dependent on the technological errors of LTs. Therefore, the performance of non-plyometric exercises, carried out in the Smith machine and with an isometric phase in the execution of the movement, will help to minimise the technological error of the LTs.
... An incremental loading test was carried out, in which the initial load was established at 30 kg and was gradually increased in 10 kg steps until mean barbell velocity was below 0.50 m/s (i.e., around 80% of 1RM). Afterward, the load was increased from 5 kg and at the end of the test, with speeds close to 0.30 m/s, increments of 1 kg were made to reach 1RM in the most precise way [42,43]. The value of 1RM was considered the load interpolated in the force-velocity profile with the average acceleration velocity value for the halfsquat exercise of 0.30 m/s [44]. ...
... An incremental loading test was carried out, in which the initial load was established at 30 kg and was gradually increased in 10 kg steps until mean barbell velocity was below 0.50 m/s (i.e., around 80% of 1RM). Afterward, the load was increased from 5 kg and at the end of the test, with speeds close to 0.30 m/s, increments of 1 kg were made to reach 1RM in the most precise way [42,43]. The value of 1RM was considered the load interpolated in the force-velocity profile with the average acceleration velocity value for the half-squat exercise of 0.30 m/s [44]. ...
Article
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The purpose of this study was to verify if a conditioning activity was effective to elicit postactivation performance enhancement (PAPE) and to increase the performance in vertical jump (VJ) in elite female volleyball players. Eleven national Superliga-2 volleyball players (22.6 ± 3.5 years) were randomly assigned to an experimental and control group. Countermovement jumps (CMJ) were performed on eight occasions: before (Pre-PAPE) and after activation (Post-PAPE), after the match (Pre-Match), and after each of the five-match sets (Set 1 to 5). ANOVA showed significantly increased jump performance for the experiment between baseline (Pre-PAPE) and all the following tests: +1.3 cm (Post-PAPE), +3.0 cm (Pre-Match), +4.8 cm (Set 1), +7.3 cm (Set 2), +5.1 cm (Set 3), +3.6 cm (Set 4), and +4.0 cm (Set 5), all showing medium to large effect size (0.7 < ES < 2.4). The performance of the control group did not show significant increases until Set 3 (+3.2 cm) and Set 5 (+2.9 cm), although jump heights were always lower for the control group than the experimental. The use of conditioning activity generates increased VJ performance in Post-PAPE tests and elicited larger PAPE effects that remain until the second set of a volleyball match.
... The participants were instructed to perform each repetition with an eccentric phase of 2 s duration and a maximal velocity in the concentric phase of the movement [26,27]. The participants started from an upright position, with the knees and hips fully extended, their stance approximately shoulder-width apart, with both feet positioned flat on the floor in parallel or externally rotated to a maximum of 15 • [28]. The stance width and foot position were individually adjusted and carefully replicated on every lift. ...
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Although velocity control in resistance training is widely studied, its utilization in eliciting post-activation performance enhancement (PAPE) responses receives little attention. Therefore, this study aimed to evaluate the effectiveness of heavy-loaded barbell squats (BS) with velocity loss control conditioning activity (CA) on PAPE in subsequent countermovement jump (CMJ) performance. Sixteen resistance-trained female volleyball players participated in this study (age: 24 ± 5 yrs.; body mass: 63.5 ± 5.2 kg; height: 170 ± 6 cm; relative BS one-repetition maximum (1RM): 1.45 ± 0.19 kg/body mass). Each participant performed two different conditions: a set of the BS at 80% 1 RM with repetitions performed until a mean velocity loss of 10% as the CA or a control condition without CA (CNTRL). To assess changes in jump height (JH) and relative mean power output (MP), the CMJ was performed 5 min before and throughout the 10 min after the CA. The two-way analysis of variance with repeated measures showed a significant main effect of condition (p = 0.008; η2 = 0.387) and time (p < 0.0001; η2 = 0.257) for JH. The post hoc test showed a significant decrease in the 10th min in comparison to the value from baseline (p < 0.006) for the CNTRL condition. For the MP, a significant interaction (p = 0.045; η2 = 0.138) was found. The post hoc test showed a significant decrease in the 10th min in comparison to the values from baseline (p < 0.006) for the CNTRL condition. No significant differences were found between all of the time points and the baseline value for the CA condition. The CA used in the current study fails to enhance subsequent countermovement jump performance in female volleyball players. However, the individual analysis showed that 9 out of the 16 participants (56%) responded positively to the applied CA, suggesting that the PAPE effect may be individually dependent and should be carefully verified before implementation in a training program.
... Associations between maximal and explosive strength capacities are best displayed by individual load-velocity profiles [13]. A plethora of studies analyzed load-velocity profiles using a linear velocity transducer in various settings, concluding that velocitybased monitoring of strength performance is a precise method to assess the effort and the estimated relative load of athletes [14][15][16][17]. In addition, the force-power relationship has recently received more attention in helping to maximize power performances in ballistic and multi-joint exercises [18][19][20]. ...
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This study assessed the effects of a 7-day creatine (CRE) supplementation on the load–velocity profile and repeated sub-maximal bouts in the deep squat using mean propulsive velocity (MPV) and mean propulsive power (MPP). Eleven strength-trained men (31.4 ± 5.4 years) supplemented 0.3 g·kg−1·d−1 CRE or a placebo (PLA, maltodextrin) for seven days in a randomized order, sepa-rated by a 30-day washout period. Prior to and after the supplementation, the subjects performed an incremental maximal strength (1RM) test, as well as 3 × 10 repetitions and a repeti-tions-to-failure test (RFT), all at 70% 1RM. Maximal strength remained statistically unaltered in CRE (p = 0.107) and PLA (p = 0.568). No statistical main effect for time (p = 0.780) or interaction (p = 0.737) was observed for the load–velocity profile. The number of repetitions during RFT remained statistically unaltered in both conditions (CRE: +16.8 ± 32.8%, p = 0.112; PLA: +8.2 ± 47.2%, p = 0.370), but the effect size was larger in creatine compared to placebo (g = 0.51 vs. g = 0.01). The total work during RFT increased following creatine supplementation (+23.1 ± 35.9%, p = 0.043, g = 0.70) but remained statistically unaltered in the placebo condition (+15.0 ± 60.8%, p = 0.801, g = 0.08; between conditions: p = 0.410, g = 0.25). We showed that CRE loading over seven days did not affect load–velocity characteristics but may have increased total work and power output during submaximal deep squat protocols, as was indicated by moderate effect sizes.
... In this way, one cannot determine the true technical error of a given device (i.e., to discern it from the biological variation). Since very minor changes in velocity could imply significant changes in daily readiness to train (14,24,36), examining the reproducibility of a given device is necessary before it can be used in practical settings. ...
Article
Jovanovic, M and Jukic, I. Within-unit reliability and between-units agreement of the commercially available linear position transducer and barbell-mounted inertial sensor to measure movement velocity. J Strength Cond Res XX(X): 000-000, 2020-The purpose of this study was to investigate the within-unit reliability of GymAware linear position transducer (GYM) and PUSH2 inertial sensor to measure mean velocity (MV) and peak velocity (PV) during hexagonal barbell deadlift (HBD) and to examine the agreement between GYM and PUSH2 devices. Twelve strength-trained men performed 2 HBD one-repetition maximum (1RM) sessions followed by 2 repetitions to failure assessments with 80 and 90% of daily 1RM. Barbell MV and PV were simultaneously monitored with 2 GYM and PUSH2 devices during all assessments. An ordinary least products regression was used to assess within-units agreement and whether PUSH2 can accurately predict GYM velocity. In addition, residual standard error (RSE) and smallest detectable change in load (SDC%1RM) were also calculated. GYM devices have been shown to be highly reproducible devices (RSE 5 0.019-0.021 m·s 21 ; SDC%1RM 5 1.795-2.679%). However, PUSH2 devices displayed a substantial amount of error (RSE 5 0.133-0.220 m·s 21) and lack of sensitivity (SCD%1RM 5 14.113-14.558%) to detect smallest change in load, which makes them untrustworthy for a regular use for monitoring athletes. Although very high correlations (r 5 0.915-0.948) have been observed between PUSH2 and GYM velocity recordings, PUSH2 overestimated both MV and PV as indicated by high fixed and proportional bias. The findings of the present study suggest that sport professionals should not use PUSH2 devices when the aim is to accurately monitor velocity variables during HBD exercise because low within-unit agreement and high fixed and proportional bias and RSE compared with GYM devices may compromise the utility of the collected data.
... All training variables including relative intensity (60-80% 1RM), number of sets (4-5 sets), number of repetitions (8-4 repetitions), between-set recovery (4 min), and between-session recovery (72 h) were identical for all participants of the TRAIN group. In this group, relative loads were determined from the load-velocity relationship of the full squat exercise [23]. Thus, a target mean propulsive velocity to be attained in the first (usually the fastest) repetition of each training session was used as an accurate estimation of load magnitude [24]. ...
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This study aimed to analyze the validity and sensitivity of two time-shortened Wingate anaerobic tests (WAnTs), by means of three phases. In Phase A, 40 participants performed a traditional 30 s WAnT, whereas the first 15 s (WAnT15) and 20 s (WAnT20) were used to elaborate two predictive models. In Phase B, another 30 s WAnT was performed by 15 different volunteers to examine the error of these models (cross-validation). Finally, in Phase C, a 30 s WAnT was registered before and after a 10-week velocity-based training conducted by 22 different participants (training group, TRAIN = 11; control group that fully refrained from any type of training, CONTROL = 11). Power changes (in Watts, W) after this training intervention were used to interpret the sensitivity of the time-shortened WAnT. Adjusted coefficient of determination (R2) was reported for each regression model, whereas the cross-validation analysis included the smallest detectable change (SDC) and bias. Close relationships were found between the traditional 30 s WAnT and both the WAnT15 (R2 = 0.98) and WAnT20 (R2 = 0.99). Cross-validation analysis showed a lower error and bias for WAnT20 (SDC = 9.3 W, bias = −0.1 W) compared to WAnT15 (SDC = 22.2 W, bias = 1.8 W). Lastly, sensitivity to identify individual changes was higher for WAnT20 (TRAIN = 11/11 subjects, CONTROL = 9/11 subjects) than for WAnT15 (TRAIN = 4/11 subjects, CONTROL = 2/11 subjects). These findings suggest that the WAnT20 could become a valid and sensitive protocol to replace the traditional 30 s WAnT.
... It was found that MV is the best way to determine resistance exercise intensity [3,4,[27][28][29][30][31]. These studies showed a strong, almost perfect relationship between relative load (%1RM) and MV in many resistance exercises [11,[32][33][34]. Thus, when measuring MV it is possible to estimate precisely what %1RM a specific load (kg) represents from the first repetition performed at the maximum possible velocity during a resistance exercise. ...
Article
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Introduction: Aiming a more effective intensity control in resistance training (RT), the measurement of movement velocity (MV) has gained attention from the scientific community and strength and conditioning professionals. Objectives: First, to analyze from a critical point of view the indicators that serve as a reference for the expression and control of intensity in the RT. These indicators created from the world of bodybuilding have been used for decades, without any relevant modification, to improve the physical performance of athletes from different sports. The second objective was to describe a rational and precise proposal for the best determination and control of intensity in the RT. Methods: Systematic review articles with and without meta-analysis and clinical trials on the measurement of MV in RT were selected. Conclusion: Monitoring MV allows more precise control of the RT intensity.Keywords: exercise, velocity measurement, muscle strength.
... Hence, this may be a possible reason why we did not observe a relative strength effect in current study at 6 hours. However, half squat presents a lower velocity associated to 1RM which allow to increase the total external load (and modify velocity-and power-load relationships) lifted in comparison to parallel squat [30]. ...
Article
This study aimed to identify the effects of same day resistance priming exercise on countermovement jump parameters and subjective readiness, and to identify whether baseline strength level influenced these outcomes. Fourteen participants performed two separate conditions (Priming [2 sets high-load parallel squats with a 20% velocity loss cut-off] and Control) in a randomized, counterbalanced crossover design. Countermovement jump was assessed at pre, post and 6h while readiness was assessed at pre and at 6h only. All countermovement jump force-time metrics were similar between conditions (p>0.05), but different individual responses were noted 6h after priming. Jump height was increased for 4/14, decreased for another 4/14 and maintained for 6/14 participants at 6h. Higher perceived physical performance capability (p<0.001) and activation balance (p=0.005) were observed after priming only. Positive relationships were observed between strength and the percentage change in jump height (r=0.47-0.50; p=0.033-0.042), concentric peak velocity (r=0.48-0.51; p=0.030-0.041) and impulse (r=0.47; p=0.030-0.045) at post and 6h after priming exercise. These findings suggest that velocity-based high-load low-volume priming exercise has potential to positively impact jump performance and subjective readiness later that day in certain individuals. Participant absolute strength level may influence this response but should be confirmed in subsequent studies.
... This cross-sectional study was designed to test the load-velocity (R² ≥ 0.90, CV ≤ 5%, and ICC ≥ 0.90) [11,18]. Furthermore, the inclusion of very-light relative intensities (i.e., ~20% JS-1RM) in the linear regressions allows coaches to precisely determine and prescribe lighter and faster JS loads, which seem to be essential to improve the athlete's ability to apply force at higher movement velocities [4, 6, 23,24]. ...
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The purpose of this study was to test the load-velocity relationship in the jump squat (JS) exercise using three different velocity parameters (mean velocity [MV], mean propulsive velocity [MPV], and peak velocity [PV]). Twenty-six male rugby union players (24.3 ± 3.9 years; 1.81 ± 0.09 m; 101.3 ± 15.4 kg) performed a progressive loading test in the JS with loads corresponding to 20, 40, 60, and 80% of the half-squat 1RM (equivalent to 24, 46, 70, and 94% of the estimated JS-1RM). MV, MPV, and PV were continuously recorded during all attempts using a linear velocity transducer. Linear regression models were used to determine the relationships between JS loads and MV, MPV, and PV. Bar-velocity outputs demonstrated high levels of consistency and reliability (coefficient of variation ≤ 5% and intraclass correlation coefficient ≥ 0.90). The predictive power of MV, MPV, and PV were ≥ 91%, for all tested variables (P < 0.0001). The equations and bar-velocity values provided in this study can be used by coaches to precisely determine and prescribe JS training loads, from very-light to heavy loading conditions (i.e., ~20-100% JS 1RM).
... The strength coaches were present throughout the procedure of 1RM testing. The athletes started from an upright position, with the knees and hips fully extended, the stance approximately shoulder-width apart with both feet positioned flat on the floor in parallel or externally rotated to a maximum of 15° [20], hands were placed on the hand grips, and this setting was carefully replicated on every lift. From this position, they were required to descend until contact with the bench (without losing muscle tension) and then perform the concentric phase of the movement in an explosive manner. ...
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The aim of this study was to investigate the relationship between linear sprint, power output obtained during a squat and change of direction (COD) performance. Fifteen elite soccer players participated in this study (age = 21.7 ± 0.72 years, body mass = 74.9 ± 9.11 kg, body height = 180.4 ± 7 cm, training experience = 9 ± 1.5 years). To examine these correlations a following battery of tests were carried out: 20-m linear sprint, one-repetition maximum (1RM) squat strength, peak power output obtained during a squat at 50% 1RM and time obtained in two 20-m COD tests with different angles of direction change (90° and 135°). In addition, COD deficits (90°-CODDEF and 135°-CODDEF) for both COD tests were calculated. The Spearman's rank order correlation showed a nearly perfect statistical relationship between the 90°-COD and the 90°-CODDEF (r = 0.9; p < 0.001). In the case of 90°-CODDEF, there was a large statistical relationship with 135°-CODDEF (r = 0.59; p = 0.021). Moreover, there was a nearly perfect statistical relationship between 135°-COD and 135°-CODDEF (r = 0.91; p < 0.001). The statistically insignificant (p > 0.05) relationship between 20-m linear sprint time, power output obtained during a squat at 50% 1RM, 1RM squat strength level and both COD test, as well as both COD deficits were found. Results of the present study showed that 20-m linear sprinting speed, 1RM squat strength, power output obtained during squat at 50% 1RM and COD ability at 90° and 135° angles, are separate physical qualities. Moreover, it seems that COD deficit provides a more isolated measure of COD ability than the COD tests alone and does not must be limited to a specific angle, but provides knowledge about the COD ability in a range of other angles, at least concerning 90° and 135° COD angles.
... Mean bar velocity (MV) was obtained as the mean of the two repetitions, while peak bar velocity (PV) was obtained from the best repetition in each set. During the squat exercise, technical criteria were applied in accordance with Martínez-Cava et al. (2019) and according to the rules of the International Powerlifting Federation (Wilk et al., 2020c). ...
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The main goal of the present study was to evaluate the effects of different blood flow restriction (BFR) protocols (continuous and intermittent) on peak bar velocity (PV) and mean bar velocity (MV) during the squat exercise at progressive loads, from 40 to 90 %1RM. Eleven healthy men (age = 23.4 ± 3.1 years; body mass = 88.5 ± 12.1 kg; squat 1RM = 183.2 ± 30.7 kg; resistance training experience 5.7 ± 3.6 years), performed experimental sessions once a week for 3 weeks in random and counterbalanced order: without BFR (NO-BFR); with intermittent BFR (I-BFR) and with continuous BFR (C-BFR). During the experimental session, the participants performed six sets of the barbell squat exercise with loads from 40 to 90% 1RM. In each set they performed two repetitions. During the C-BFR session the cuffs were maintained throughout the training session. During the I-BFR, the cuffs were used only during the exercise and released for each rest interval. The BFR pressure was set to ~80% AOP Analyses of variance showed a statistically significant interaction for MV (p < 0.02; η2 = 0.18). However, the post hoc analysis did not show significant differences between particular conditions for particular loads. There was no significant condition × load interaction for PV (p = 0.16; η2 = 0.13). Further there were no main effects for conditions in MV (p = 0.38; η2 = 0.09), as well as in PV (p = 0.94; η2 = 0.01). The results indicate that the different BFR protocols used during lower body resistance exercises did not reduce peak bar velocity and mean bar velocity during the squat exercise performed with various loads.
... the reliable and valid assessment of back squat mechanics provides useful information for S&c coaches and physical therapists regarding an individual's functional capacities or risk of injury. For instance, variation in squat depth is known to influence the development of kinetic and kinematic outcomes (martinez-Cava, moran-navarro, Sanchez-medina, gonzalez-Badillo, Pallares, 2019;rhea et al., 2016). While abnormal lower extremity kinematics during a deep squat may infer movement limitations stemming from mobility issues (Kim, Kwon, Park, jeon, Weon, 2015;List, gulay, Stoop, Lorenzetti, 2013;Macrum, Bell, Boling, Lewek, Padua, 2012). ...
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This study examined the test re-test, intrarater and interrater reliability of joint kinematics from the coach's Eye smartphone application. Twenty-two males completed a 1-repetition maximum (1-rM) assessment followed by 2 identical sessions using 5 incremental loads (20, 40, 60, 80, 90% 1-rM). Peak flexion angles at the hip, knee, and ankle joints were assessed using 1 experienced practitioner and 1 inexperienced practitioner. the acceptable reliability thresholds were defined as intraclass correlation coefficient (Icc) r > 0.70 and coefficient of variation cv ≤ 10%. the test re-test reliability of peak hip and knee flexion were reliable across 20-90% 1-rM (r > 0.64; cv < 4.2%), whereas peak ankle flexion was not reliable at any loaded condition (r > 0.70; cv < 20.4%). no significant differences were detected between trials (p > 0.11). the intrarater reliability was near perfect (r > 0.90) except for peak ankle flexion (r > 0.85). the interrater reliability was nearly perfect (r > 0.91) except for hip flexion at 80% 1-rM and ankle flexion at 20% (r > 0.77). concludingly, the coach's Eye application can produce repeatable assessments of joint kinematics using either a single examiner or 2 examiners, regardless of experience level. the coach's Eye can accurately monitor squat depth.
... The range of motion of the FS was defined as the beginning of the movement in an upright posture, with hips and knees fully extended, barbell resting on the shoulders and feet flat on the floor, spaced approximately shoulder-width apart, parallel or externally rotated to a maximum of 15° (point A). Participants descended in controlled motion from this position until the back of the thigh touched the calf (point B; Hartmann et al., 2013;Martínez-Cava et al., 2019). After that phase (with a brief pause during the incremental testing), they returned to point A (Pallarés et al., 2014). ...
Article
This study analyzed the acute mechanical response to three workouts of the day (WOD) protocols in as many repetitions as possible (AMRAP), every minute on the minute (EMOM), and for time (FT) models by quantifying the degree of mechanical fatigue induced by popular resistance exercises in the Cross modalities, front squat (FS), and shoulder press (SP). Besides, we analyzed whether the exercises’ fastest velocity (Vfastest) could be an objective indicator of relative intensity (%1RM). Nine trained men performed three FS and SP exercises protocols. The degree of fatigue was quantified by the velocity loss (VL) achieved in both exercises and the velocity loss achieved in the WOD (VLWOD). The VLWOD in the AMRAP, EMOM, and FT protocols was 73.2 ± 10.9%, 61.6 ± 15.1%, and 76.1 ± 8.8%, respectively. In the AMRAP and FT protocol, the Vfastest showed very strong relationships with the %1RM for FS and SP (r = -0.83, -0.75, respectively, p<0.01); while in the EMOM protocol, there was a strong relationship between these variables, only for the SP (r = -0.61, p<0.05). In the FT protocol, we observed an extremely strong relationship for FS (r = -0.91, p<0.001) and very strong (r = -0.71, p<0.05) for SP between these variables. Therefore, the AMRAP and FT training models induce the highest degrees of mechanical fatigue in the FS and SP exercises, and the Vfastest is a reliable tool for estimating relative intensity in resistance exercises of Cross modalities.
... In order to assess SPC, exercises should be selected that provide a transfer to the sport in skill movement and strength. Thus, the squat (SQ) and the bench press (BP) are two of the most used and effective exercises in resistance training for strengthening the lower and the upper body for improving athletic performance [29,30]. ...
Article
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Rugby players need muscular strength and power to meet the demands of the sport; therefore , a proper assessment of the performance in rugby players should include both variables. The purpose of this study was to examine the strength and power characteristics (SPC) during the squat (SQ) and bench press (BP) in national amateur rugby players and to analyze gender-and position-related differences. A total of 47 players (30 males and 17 females; age: 25.56 ± 1.14 and 23.16 ± 1.38 years, respectively) participated in the study. The one repetition-maximum (1-RM) and SPC in SQ and BP were obtained using a Smith Machine. Then, subjects performed one set of five repetitions on the SQ and BP against six relative loads (30-40-50-60-70-80% 1-RM) using a linear transducer. Differences between genders were found in 1-RM for maximal power, kilograms lifted at maximal power, maximal power, maximal strength and maximal speed in BP (p < 0.00) and 1-RM, kilograms lifted at maximal power, maximal power, maximal strength and maximal speed in SQ (p < 0.00). Comparisons between variables in SQ and BP present a significant relationship (p < 0.01) in SQ and BP 1-RM with kilograms lifted at maximal power (r = 0.86 and r = 0.84), maximal strength (r = 0.53 and r = 0.92) and maximal power (r = 0.76 and r = 0.93). This study confirms the importance of the SPC assessment for training prescription in rugby amateur players.
... 7,8 Firstly, strong relationships (R 2 = .94-.98) between %1RM and movement velocity have been reported for exercises conducted on Smith machine such as bench press (BP), 8 prone bench pull, 9 pull-up, 10 and different squat variants. 11,12 Notably, it has also been reported that these relationships are not affected by individual strength levels or training background. 13,14 These strong relationships open up the possibility of prescribing exercise intensity on a daily basis by adjusting the absolute load (kg) to match the movement velocity associated with the %1RM that is scheduled for the training session. ...
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Objective This study aimed to compare the effects of four velocity‐based training (VBT) programs in bench‐press (BP) between a wide range of velocity loss (VL) thresholds – 0% (VL0), 15% (VL15), 25% (VL25) and 50% (VL50) – on strength gains, neuromuscular adaptations and muscle hypertrophy. Methods Sixty‐four resistance‐trained young men were randomly assigned into four groups (VL0, VL15, VL25, and VL50) that differed in the VL allowed in each set. Subjects followed a VBT program for 8‐weeks using the BP exercise. Before and after the VBT program the following tests were performed: 1) cross‐sectional area (CSA) measurements of pectoralis major (PM) muscle; 2) maximal isometric test; 3) progressive loading test; and 4) fatigue test. Results Significant group x time interactions were observed for CSA (P<0.01) and peak root mean square in PM (peak RMS‐PM, P<0.05). VL50 showed significantly greater gains in CSA than VL0 (P<0.05). Only the VL15 group showed significant increases in peak RMS‐PM (P<0.01). Moreover, only VL0 showed significant gains in the early rate of force development (RFD, P=0.05), while VL25 and VL50 improved in the late RFD (P≤0.01–0.05). No significant group × time interactions were found for any of the dynamic strength variables analyzed, although all groups showed significant improvements in all these parameters. Conclusion Higher VL thresholds allowed for a greater volume load which maximized muscle hypertrophy, whereas lower VL thresholds evoked positive neuromuscular‐related adaptations. No significant differences were found between groups for strength gains, despite the wide differences in the total volume accumulated by each group.
... Apart from 3D motion capturing, which are considered "gold standard," linear position-velocity transducers generally seem to obtain valid and reliable movement velocities (21). Especially, the T-Force system has been used in various research settings (18,22,24) and has been validated in numerous studies, showing an excellent validity and reliability when compared with camera-based motion capturing and linear velocity-position transducer (4). Compared with other systems, IMUs do not depend on a cable-extension or a multi-camera system and are easily attached to the body or the barbell (2). ...
Article
We aimed at assessing the validity and test-retest reliability of the inertial measurement unit-based Vmaxpro sensor compared with a Vicon 3D motion capture system and the T-Force sensor during an incremental 1-repetition maximum (1RM) test and at submaximal loads. Nineteen subjects reported to the laboratory for the 1RM test sessions, whereas 15 subjects carried out another 3 sessions consisting of 3 repetitions with 4 different intensities (30, 50, 70, and 90% of 1RM) to determine the intra- and interday reliability. The Vmaxpro sensor showed high validity (Vicon: R2 = 0.935; T-Force: R2 = 0.968) but an overestimation of the mean velocities (MVs) of 0.06 ± 0.08 m·s−1 and 0.06 ± 0.06 m·s−1 compared with Vicon and T-Force, respectively. Regression analysis indicated a systematic bias that is increasing with higher MVs. The intraclass correlation coefficients (ICCs) for Vmaxpro were moderate to high for intraday (ICC: 0.662–0.938; p ≤ 0.05) and for interday (ICC: 0.568–0.837; p ≤ 0.05) reliability, respectively. The Vmaxpro is a valid and reliable measurement device that can be used to monitor movement velocities within a training session. However, practitioners should be cautious when assessing movement velocities on separate days because of the moderate interday reliability.
... The bar was required to remain in contact with the back and shoulders at all times. From this position, they were required to descend until making contact the upper leg was horizontal [30,31]. ...
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Background: Resistance training is a significant part of ice-hockey players’ conditioning, where optimal loading should ensure strength development and proper recovery. Therefore, this study aimed to compare the acute physiological responses to fast and medium movement tempo resistance exercises in ice-hockey players. Methods: Fourteen ice-hockey players (26.2 � 4.2 years; 86.4 � 10.2 kg; squat one repetition maximum (1RM) = 130.5 � 18.5) performed five sets of the barbell squat and barbell bench press at 80% 1RM until failure in a crossover design one week apart using either 2/0/2/0 or 6/0/2/0 (eccentric/isometric/concentric/isometric) tempo of movement. The blood samples to evaluate the concentration of cortisol, testosterone, insulin-like growth factor 1 (IGF-1), and growth hormone (hGH) were taken before exercise, 3 min after the last set of the squat exercise, 3 min after the last set of the bench press exercise, and after 30 min of recovery. Results: The 2/0/2/0 tempo resulted in a higher number of repetitions (p < 0.001) and lower time under tension (p < 0.001) in the squat and bench press exercises compared to the 6/0/2/0 movement tempo. The endocrine responses to exercise were significantly higher during the 2/0/2/0 compared to the 6/0/2/0 movement tempo protocol for IGF-1, hGH, and cortisol (p < 0.01). There were no differences in testosterone responses between exercises performed with fast and medium movement tempos. Conclusion: Fast eccentric tempo induced higher cortisol, IGF-1, and hGH responses compared to the medium tempo. Therefore, fast eccentric movement tempo seems to be more useful in eliciting training stimulus than medium eccentric tempo during resistance training in ice-hockey players. However, future studies are needed to confirm our findings.
... The very strong relationship between submaximal loads and bar velocity (R 2 > .94; standard error of the estimation = 5.43% 1RM) found here suggests that bar velocity can accurately estimate the 1RM in the HBD exercise, which is consistent with previous studies including other resistance exercises such as bench press (González-Badillo & Sánchez-Medina, 2010; Loturco et al., 2017), back squat (Conceição et al., 2016;Martínez-Cava et al., 2019), prone row Loturco et al., 2021), and conventional deadlift (Benavides-Ubric et al., 2020;Morán-Navarro et al., 2021). Nevertheless, the individual load-velocity relationship provided an even better adjustment than the general equation (R 2 > .97). ...
Article
In this study, we examined the load-velocity relationship in the hexagonal bar deadlift exercise in women. Twenty-seven resistance-trained women were recruited. Participants performed a progressive load test up to the one-repetition maximum (1RM) load for determining the individual load-velocity relationship in the hexagonal bar deadlift exercise. Bar velocity was measured in every repetition through a linear encoder. A very strong and negative relationship was found between the %1RM and bar velocity for the linear (R 2 = .94; standard error of the estimation = 5.43% 1RM) and second-order polynomial (R 2 = .95) regression models. The individual load-velocity relationship provided even better adjustments (R 2 = .98; coefficient of variation = 1.77%) than the general equation. High agreement level and low bias were found between actual and predicted 1RM for the general load-velocity relationship (intraclass correlation coefficient = .97 and 95% confidence interval [0.90, 0.99]; bias = −2.59 kg). In conclusion, bar velocity can be used to predict 1RM with high accuracy during hexagonal bar deadlift exercise in resistance-trained women.
... m·s 21 . This means that the players started this period using a HS load corresponding to ;85% 1RM (0.4 m·s 21 ) and continued to use heavy loads ($75% 1RM, ;0.5 m·s 21 ) for a substantial period of time (33). Indeed, the adverse effects and "reduced levels of transference" of strength training with heavy loads to maximum sprint speed have been extensively reported in the literature, and these effects may be even more pronounced in soccer players (9,22,25,34). ...
Article
Maximizing the neuromuscular capacities of players is a critical challenge during short soccer preseasons. This study compared the effects of two strength-power training regimes, on the strength, speed, and power performance of elite young soccer players during a 4-week preseason. Twenty-five under-20 players from the same club were pair-matched in two training groups as follows: traditional training group (TTG) (n=13), athletes performed half-squat (HS) and jump-squat (JS) exercises as traditionally prescribed; and EB group (EBG) (n=12), athletes performed HS and JS with EB attached to the barbell. Vertical jump height, 20-m sprint velocity, change-of-direction (COD) speed, HS and JS power, and one-repetition maximum (1RM) in the HS were assessed pre, post 2-week, and post 4-week of training. An ANOVA two-way with repeated measures was used to assess the effects of both training protocols over the experimental period. Both strategies were effective for significantly improving HS and JS power (effect sizes [ES] 1.00 - 1.77), HS 1RM (ES = 1.68 and 1.51 for TTG and EBG, respectively), vertical jumping ability (ES 0.37 - 0.65), and COD speed (ES = 0.81 and 0.39 for TTG and EBG, respectively), when comparing pre- and post-measures. In contrast, both TTG and EBG failed to increase 20-m sprint velocity (ES ranging between -0.54 and 0.23). In conclusion, both training schemes were able to improve the strength and power performance, but not the sprint capacity of young soccer players. To accelerate strength gains over very-short time periods (i.e., 2-week), variable resistance training may be advantageous. Conversely, to optimize power adaptations in ballistic exercises across a similar time period, traditional FW training may be preferred.
Article
The aims of this study were to investigate the impact of high-intensity, low-volume (HRT) vs. moderate-intensity, high-volume resistance training (MRT) vs. soccer training only (CON) on changes in strength, power, and speed, and to compare delayed onset muscle soreness (DOMS) between groups in male academy soccer players (ASP). Twenty-two ASP (age: 18±1 years) were assigned to either HRT (n=8), MRT (n=7) or CON (n=7). HRT completed 2 sets of 4 repetitions parallel back squat (PBS) repetitions at 90% 1RM, while MRT performed 3 sets of 8 repetitions PBS repetitions at 80% 1RM, both once a week for six-weeks in-season, alongside regular soccer training. All groups completed the following pre- and post-training assessments: 3RM PBS; bilateral vertical and horizontal countermovement jumps (CMJ); squat jump (SJ); 30m sprint. DOMS was assessed via visual analogue scale throughout training. HRT and MRT experienced similar increases compared to CON in absolute PBS 3RM (p<0.001), SJ height (p=0.001), CMJ height (p=0.008) following training. There was a greater increase in PBS 3RM relative to body mass following HRT than MRT and CON (p=0.001) and horizontal CMJ distance improved in HRT but not in MRT or CON (p=0.011). There was no change in 10m, 20m or 30m sprint performance in any group. HRT volume was 58±15% lower than that of MRT (p<0.001) and DOMS measured throughout training did not differ between groups (p=0.487). These findings suggest that one HRT session a week may be an efficient method for improving strength and power in ASP in-season with minimal DOMS.
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Objective: Acute effects of variable resistance training (VRT) and constant resistance training (CRT) on neuromuscular performance are still equivocal. We aimed to determine the differences between VRT and CRT in terms of force, velocity, and power outcomes. Methods: We searched PubMed, Web of Science, and SPORTDiscus electronic databases for articles until June 2021. Crossover design studies comparing force, velocity, and power outcomes while performing VRT and CRT were included. Two reviewers independently applied the modified version of the Cochrane Collaboration's tool to assess the risk of bias. A three-level random effects meta-analyses and meta-regressions were used to compute standardized mean differences (SMDs) and 95% confidence intervals. Results: We included 16 studies with 207 participants in the quantitative synthesis. Based on the pooled results, VRT generated greater mean velocity (SMD = 0.675; moderate Grading of Recommendations Assessment, Development and Evaluation (GRADE) quality evidence) and mean power (SMD = 1.022; low) than CRT. Subgroup analyses revealed that VRT considerably increased the mean velocity (SMD = 0.903; moderate) and mean power (SMD = 1.456; moderate) in the equated loading scheme and the mean velocity (SMD = 0.712; low) in the CRT higher loading scheme. However, VRT marginally significantly reduced peak velocity (SMD = -0.481; low) in the VRT higher loading scheme. Based on the meta-regression analysis, it was found that mean power (p = 0.014-0.043) was positively moderated by the contribution of variable resistance and peak velocity (p = 0.018) and peak power (p = 0.001-0.004) and RFD (p = 0.003) were positively moderated by variable resistance equipment, favoring elastic bands. Conclusions: VRT provides practitioners with the means of emphasizing specific force, velocity, and power outcomes. Different strategies should be considered in context of an individual's needs. Systematic review registration: PROSPERO CRD42021259205.
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Bu çalışmanın amacı, farklı yüklerde modifiye edilmiş unilateral squat performansında çömelme derinliği ile bar hızı arasındaki ilişkinin incelenmesidir. Çalışmanın örneklem grubunu, Haliç Üniversitesi Beden Eğitimi ve Spor Yüksekokulu’nda okuyan, en az üç yıl boyunca aktif egzersiz yapan, unilateral (tek taraflı) ve bilateral (iki taraflı) egzersiz modellerine hâkim; yaş 22,90±1,28yıl; boy 175,90±5,36cm ve vücut ağırlığı 75,38±7,78kg olan 10 gönüllü erkek sporcu oluşturmuştur. Verilerin toplanmasında, bar hızının tespit edilmesi için doğrusal hız ölçer olarak PUSH Band™ Pro v2.0 ve squat performansı esnasında çömelme derinliği için üç boyutlu hareket analizi sistemi olan Qualisys Track Manager (QTM) 2020.3 Versiyon (AB, İsveç) kullanılmıştır. Sporcular; modifiye tek bacak squat egzersizi uygulamışlardır. Egzersizi arkadan tutuşta her iki ekstremitede önce ağırlıksız bar da (20kg), ardından random olarak; 1TM’nin %40, %60, %80 yüklerde 5 tekrar yapacak şekilde gerçekleştirmişlerdir. Ölçümlerde, bar üzerine yerleştirilen Push Band aracılığıyla bar hızı hesaplanmış; 3D hareket analiz sistemiyle de farklı yüklerdeki çömelme derinlikleri hesaplanmıştır. Verilerin istatistiksel analizi, IBM SPSS Versiyon 25 programı kullanılarak; tekrarlı ölçümlerde varyans analizi ve ikili karşılaştırmalarda T-testi uygulanarak yapılmıştır. Farklı relatif yüklerde bar hızlarının hemen hepsinde anlamlı farklılıklar elde edilmiştir (p<0,05). Yapılan korelasyon analizi sonucunda bar hızı ve çömelme derinliği arasında anlamlı bir ilişki olmadığı tespit edilmiştir (p>0,05). Sonuç olarak, farklı yüklerdeki bar hızı değişkenlerinin her iki ekstremite de yüklerin artmasıyla anlamlı değişikliklere sebep olmuştur. Yük miktarı, barı hızını azaltacak yönde etkileyen bir parametre olarak değerlendirilebilir.
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The main goal of this study was to assess the impact of the cambered bar (CB) during the bench press exercise on power output and bar velocity when compared to a standard bar (SB). Ten healthy strength-trained men (age = 27.9 ± 3.7 years; body mass = 90.1 ± 12.5 kg; resistance training experience = 6.5 ± 2.7 years; bench press one-repetition maximum (1RM) = 118.5 ± 21 kg) performed a single set of 3 repetitions of the bench press exercise with an SB and a CB at 50%1RM to assess differences in peak power output (PP), mean power output (MP), peak bar velocity (PV), and mean bar velocity (MV), range of motion (ROM), and positive work time under load (TUL) between conditions. The t-test indicated significantly higher mean ROM for the cambered bar in comparison to the standard bar (52.7 vs. 44.9 cm; P < 0.01; ES = 1.40). Further, there was a significantly higher PP (907 vs. 817 W; P < 0.01; ES = 0.35), MP (556 vs. 496 W; P < 0.01; ES = 0.46), PV (1.24 vs. 1.14 m/s; P < 0.01; ES = 0.35) and MV (0.89 vs. 0.82 m/s; P < 0.01; ES = 0.34) for the CB condition when compared to the SB. A significantly longer TUL for the CB was observed, when compared to the SB (1.89 vs. 1.51 s; P < 0.01; ES = 1.38). The results of this study showed that the CB significantly increased power output and bar velocity in the bench press exercise at 50%1RM compared to the SB. Therefore, the additional ROM, made possible through the use of the CB, allows for the acceleration of the bar through a significantly longer displacement, which has a positive impact on power output. However, a simultaneous increase in TUL may cause higher fatigue when the bench press is performed with the CB compared to the SB.
Chapter
Currently, velocity-based training (VBT) is one of the hot topics in sport science and among strength and conditioning coaches. However, its wide use has spread some misunderstandings of the fundamental concepts of this methodology. It should be highlighted that this is not a new training method, but rather, a new approach that enables more accurate, frequent, and objective control of resistance training intensity and volume. The VBT approach is no other thing than recording lifting velocity every repetition during resistance training. The quantification of actual repetition velocities achieved during resistance training sessions provides a more consistent and precise understanding of training effects, opening up the possibility to establish causal relationships between stimuli and response, which is one of the main and most important targets of research and practice in sport science. As such, VBT can be defined as a resistance training method that uses movement velocity to improve training process and enhance training effects, via a deeper understanding of the input signal (actual training load) and the output signal (changes in performance). Through this chapter we will see how VBT contributes to improve the resistance training methodology, as well as discuss its potential benefits, limitations, and practical implications.
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Introduction: In modern gymnastics, there are high demands for the physical quality of Chinese athletes. Objectives: This paper mainly studies whether the workload of Chinese gymnasts can support the corresponding high-intensity training in the training process. Methods: Experimental scientific research methods and statistical analysis are used to conduct a long-term study on dozens of gymnasts in Chinese schools and draw the workload curves of these gymnasts during gymnastic exercises. We try to determine the effective correlation between the athlete's body load and physical training and body shape. Results: During the training of gymnasts, heart rates can briefly exceed 190 beats per minute. Conclusion: In the training process of different gymnasts, the gymnasts’ heart rates show obvious differences. Therefore, the use of scientific and reasonable training strategies can effectively improve the ability of athletes’ hearts to withstand high-intensity exercise loads and help improve the gymnast's performance. Level of evidence II; Therapeutic studies - investigation of treatment results.
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This study analyzed the predictive ability of movement velocity to estimate the relative load (i.e., % of one-repetition maximum [1RM]) during the horizontal leg-press exercise in older women and men. Twenty-four women and fourteen men living in community-dwelling centers volunteered to participate in this study. All participants performed a progressive loading test up to 1RM in the horizontal leg-press. The fastest peak velocity (PV) and mean velocity (MV) attained with each weight were collected for analysis. Linear regression equations were modeled for women and men. We observed very strong linear relationships between both velocity variables and the relative load in the horizontal leg-press in women (PV: r² = 0.93 and standard error of the estimate (SEE) = 5.96% 1RM; MV: r² = 0.94 and SEE = 5.59% 1RM) and men (PV: r² = 0.93 and SEE = 5.96% 1RM; MV: r² = 0.94 and SEE = 5.97% 1RM). The actual 1RM and the estimated 1RM using both the PV and MV presented trivial differences and very strong relationships (r = 0.98–0.99) in both sexes. Men presented significantly higher (p < 0.001–0.05) estimated PV and MV against all relative loads compared to women (average PV = 0.81 vs. 0.69 m·s⁻¹ and average MV = 0.44 vs. 0.38 m·s⁻¹). Our data suggest that movement velocity accurately estimates the relative load during the horizontal leg-press in older women and men. Coaches and researchers can use the proposed sex-specific regression equations in the horizontal leg-press to implement velocity-monitored resistance training with older adults.
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This study aimed to evaluate the reliability and the level of agreement of the ADR encoder to measure the mean propulsive velocity (MPV) of the bar in the bench press (BP) exercise on the Smith machine. Eleven males (21.6 ± 1.5 years; body mass 76.05 ± 9.73 kg) performed the protocol with isometric phase prior to concentric muscle action (PP) and the protocol in the absence of isometric phase (N-PP) for BP exercise on Smith machine. ADR encoder reported reliability values with almost perfect correlations in all training zones and protocols (PP: ICC = 0.940–0.999, r = 0.899–0.997, CV = 1.56%–4.05%, SEM = 0.0022–0.0153,and MDC = 0.006–0.031 m/s; N-PP: ICC = 0.963–0.999, r = 0.946–0.998, CV = 0.70%–3.01%, SEM = 0.0012–0.0099, and MDC = 0.003–0.027 m/s). Although the levels of agreement were high in both protocols (PP: SEM = 0.0024–0.0204 m/s, MDC = 0.007–0.057 m/s; N-PP: SEM = 0.0034–0.0288 m/s, MDC = 0.009–0.080 m/s), ADR encoder considerably underestimated the MPV values in both protocols (PP: t = −2.239 to −9.486, p < 0.001–0.01; N-PP: t = −6.901 to −17.871, p < 0.001) with respect to the gold standard (T-Force). In conclusion, ADR encoder offers high reliability for the measurement of MPV in bench press exercise performed on Smith machine regardless of their execution mode, in the entire range of intensities. However, this device is not interchangeable with T-Force since it considerably underestimates the MPV values, especially at low loads (0%–40%). Furthermore, the use of too wide load ranges suggests that the data be interpreted with caution, pending further research to corroborate the findings presented.
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El propósito de esta investigación fue determinar el nivel de asociación entre el salto de sentadilla profunda (DSJ) y la repetición máxima en sentadilla posterior (RM), con el fin de introducir el DSJ como una herramienta de prueba de fuerza en el monitoreo y control del entrenamiento de fuerza en el Crossfit®. La muestra fue de 9 deportistas varones (edad 31.5±4.64 años; talla 171.4±3.283 cm; masa corporal 79.29±7.14 kg; IMC 26.96±2.03 kg/m2) quienes realizaron ambas pruebas. Se realizó un análisis no paramétrico para determinar la correlación entre DSJ y RM sentadilla trasera. La correlación de DSJ y RM sentadilla se calculó usando la ecuación de Spearman R (r=0.417) determinó una asociación moderada entre DSJ y el RM sentadilla trasera, con una relación no significativa (p=0.2696). Abstract The aim of this study was to determine the correlation between the deep squat jump (DSJ) and the maximum repetition in the back squat (MR), to introduce DSJ as a tool for strength testing, training monitoring and control of strength in Crossfit®. The sample was of 9 male athletes (age 31.5±4.64 y/o; high 171,4±3,283 cm; body mass 79,29±7.14 kg; BMI 26,96±2.03 kg/m2) who performed both tests (DSJ and MR back squat test). A linear regression analysis was performed to determine the correlation and, subsequently, the relationship between DSJ and RM. The correlation of DSJ and RM squat was calculated using the Spearman R equation r=0,4167 showed a moderate relationship. The results showed a non-significant relationship with values for a p=0,2696.
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The aims of this study were: i) to analyze the load-velocity relationship in the bilateral leg-press exercise in female breast cancer survivors, ii) to assess whether mean velocity (MV) or peak velocity (PV) show stronger relationship with the relative load, and iii) to examine whether linear (LA) or polynomic (PA) adjustment predict the velocities associated with each %1RM with greater precision. Twenty-two female breast cancer survivors (age: 50.2±10.8 years, weight: 69.6±15.2 kg, height: 160.51±5.25 cm) completed an incremental load test until 1RM in the bilateral leg-press exercise. The MV and the PV of the concentric phase were measured in each repetition using a linear velocity transducer, and were analyzed by regression models using LA and PA. A very close relationship of MV (R²=0.924; p<0.0001; SEE=0.08m.s⁻¹ by LA, and R²=0.952; p<0.0001; SEE=0.063 m.s⁻¹ by PA) and PV (R²=0.928; p<0.0001; SEE=0.119 m.s⁻¹ by LA and R²=0.941; p<0.0001; SEE=0.108 m.s⁻¹ by PA) with %1RM were observed. The MV of 1RM was 0.24±0.03 m·s⁻¹, whereas the PV at 1RM was 0.60±0.10 m.s⁻¹. A comprehensive analysis of the bilateral leg-press load-velocity relationship in breast cancer survivors is presented. The results suggest that MV is the most recommendable velocity variable to prescribe the relative load during resistance training, and that the PA presents better accuracy to predict velocities associated with each %1RM, although LA is sufficiently valid to use this model as an alternative to the quadratic model. The implications for resistance training in breast cancer are discussed.
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Background/objective: The aim of this study was to examine differences in bar velocity between the cambered and standard barbell bench press exercise. Methods: Ten healthy men volunteered for the study (age = 27.9 ± 3.7 years; body mass = 89.6 ± 11.7 kg; experience in resistance training 5.7 ± 2.1 years; bench press one-repetition maximum > 120% body mass). The first session aiming at the determination of the one-repetition maximum was followed by two experimental sessions consisted of performing 3 sets of 3 repetitions of the bench press exercise with the cambered or standard barbell at 50% of one-repetition maximum (of the standard barbell) in randomized order. Results: The two-way repeated measures ANOVA indicated a significant main effect of bar type on mean velocity (p=0.001; η 2 =0.739) and peak velocity (p=0.002; η 2 =0.661). The post-hoc analysis showed a significantly higher mean velocity for the cambered barbell compared to the standard barbell bench press in Set 1 (p=0.002) and Set 2 (p=0.012), but not in Set 3 (p=0.062). Moreover, there was a significantly higher mean velocity in Set 2, than in Set 1 (p=0.017) during the standard barbell bench press, with no other differences. Furthermore, a significantly higher peak velocity for the cambered barbell in comparison to the standard barbell was observed in all sets of the BP exercise (p<0.001; p=0.014; p=0.048; respectively). Conclusions: The outcomes of this investigation indicated that the cambered barbell used during the bench press training session significantly increases bar velocity compared to the standard barbell with the same external load across the workout.
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Purpose: To describe the acute and delayed time course of recovery following resistance training (RT) protocols differing in the number of repetitions (R) performed in each set (S) out of the maximum possible number (P). Methods: Ten resistance-trained men undertook three RT protocols [S × R(P)]: (1) 3 × 5(10), (2) 6 × 5(10), and (3) 3 × 10(10) in the bench press (BP) and full squat (SQ) exercises. Selected mechanical and biochemical variables were assessed at seven time points (from - 12 h to + 72 h post-exercise). Countermovement jump height (CMJ) and movement velocity against the load that elicited a 1 m s(-1) mean propulsive velocity (V1) and 75% 1RM in the BP and SQ were used as mechanical indicators of neuromuscular performance. Results: Training to muscle failure in each set [3 × 10(10)], even when compared to completing the same total exercise volume [6 × 5(10)], resulted in a significantly higher acute decline of CMJ and velocity against the V1 and 75% 1RM loads in both BP and SQ. In contrast, recovery from the 3 × 5(10) and 6 × 5(10) protocols was significantly faster between 24 and 48 h post-exercise compared to 3 × 10(10). Markers of acute (ammonia, growth hormone) and delayed (creatine kinase) fatigue showed a markedly different course of recovery between protocols, suggesting that training to failure slows down recovery up to 24-48 h post-exercise. Conclusions: RT leading to failure considerably increases the time needed for the recovery of neuromuscular function and metabolic and hormonal homeostasis. Avoiding failure would allow athletes to be in a better neuromuscular condition to undertake a new training session or competition in a shorter period of time.
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Purpose: to analyze the relationship between movement velocity and relative load (%1RM) in the pull-up exercise (PU), and to determine the pattern of repetition velocity loss during a single set to failure in pulling one's own body mass. Methods: Fifty-two men (age = 26.5 ± 3.9 years, body mass = 74.3 ± 7.2 kg) performed a first evaluation (T1) consisting of an one-repetition maximum test (1RM), and a test of maximum number of repetitions to failure pulling one's own body mass (MNR) in the PU exercise. Thirty-nine subjects performed both tests on a second occasion (T2) following 12 weeks' training. Results: We observed a strong relationship between mean propulsive velocity (MPV) and %1RM (r = -.96). Mean velocity attained with 1RM load (V1RM) was 0.20 ± 0.05 m·s(-1) and it influenced the MPV attained with each %1RM. Although 1RM increased by 3.4% from T1 to T2, the relationship between MPV and %1RM, and V1RM remained stable. We also confirmed stability in the V1RM regardless of individual relative strength. We found a strong relationship between percentage of velocity loss and percentage of performed repetitions (R(2) = .88), which remained stable despite a 15% increase in MNR. Conclusions: Monitoring repetition velocity allows estimation of the %1RM used as soon as the first repetition with a given load is performed, and the number of repetitions remaining in reserve when a given percentage of velocity loss is achieved during a PU exercise set.
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Purpose. The purpose of this study was to examine the influence of training at different ranges of motion during the squat exercise on joint-angle specific strength adaptations. Methods. Twenty eight men were randomly assigned to one of three training groups, differing only in the depth of squats (quarter squat, half squat, and full squat) performed in 16-week training intervention. Strength measures were conducted in the back squat pre-, mid-, and post-training at all three depths. Vertical jump and 40-yard sprint time were also measured. Results. Individuals in the quarter and full squat training groups improved significantly more at the specific depth at which they trained when compared to the other two groups (p < 0.05). Jump height and sprint speed improved in all groups (p < 0.05); however, the quarter squat had the greatest transfer to both outcomes. Conclusions. Consistently including quarter squats in workouts aimed at maximizing speed and jumping power can result in greater improvements.
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For the development of speed strength in professional sports, “specific” strength training in the half or the quarter squat have been recommended. Due to the better lever ratios, higher loads have to be used to induce the necessary training stimuli compared to the deep squat. Therefore, intradiscal pressure and compressive forces on vertebral bodies increase. Calculated compressive forces for the L3/L4 vertebral segment were revealed to be 6–10-fold bodyweight when the half or the quarter squat was performed with 0.8–1.6-fold bodyweight. After 10 weeks of training, physical education students have even been able to lift 3.89-fold bodyweight in the one repetition maximum (1-RM) of the quarter squat. The presented dependence of squatting depth, load and their influence on the spinal column have not been discussed before. A search for relevant scientific literature was conducted using PubMed. Concerns about increased risk of injuries in the deep squat have been disproven by plenty of cross-sectional studies with professional athletes. On the contrary, the comparably supramaximal weight loads in the half and the quarter squat should be regarded as increasing injury risks caused by the higher shear and compressive forces in the vertebral column. Therefore, we come to the conclusion that the half and the quarter squat should not further be recommended.
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Strength training-induced increases in speed-strength seem indisputable. For trainers and athletes the most efficient exercise selection in the phase of preparation is of interest. Therefore, this study determined how the selection of training exercise influences the development of speed-strength and maximal strength during an 8-week training intervention. 78 students participated in this study (39 in the training group and 39 as controls). Both groups were divided into two subgroups. The first training group (squat training group [SQ]) completed an 8-week strength training protocol using the parallel squat. The 2nd training group (leg-press training group [LP]) used the same training protocol using the leg-press (45[degrees]-leg-press). The control group was divided in two subgroups as controls for the SQ or the LP. A two-factorial analyses of variance was performed using a repeated measures model for all group comparisons and comparisons between pre- and post-test results. The SQ exhibited a statistically significant (p<0.05) increase in jump performance in Squat jump (SJ, 12.4%) and Countermovement jump (CMJ, 12.0%). Whereas, the changes in the LP did not reach statistical significance and amounted to improvements in SJ of 3.5% and CMJ 0.5%. The differences between groups were statistically significant (p<0.05). There are also indications that the squat exercise is more effective to increase Drop Jump performance. Therefore, the squat exercise increased the performance in SJ, CMJ and RSI more effectively compared to the leg-press in a short-term intervention. Consequently, if the strength training aims at improving jump performance the squat should be preferred because of the better transfer effects.
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In the context of resistance training the so-called "sticking point" is commonly understood as the position in a lift in which a disproportionately large increase in the difficulty to continue the lift is experienced. If the lift is taken to the point of momentary muscular failure, the sticking point is usually where the failure occurs. Hence the sticking point is associated with an increased chance of exercise form deterioration or breakdown. Understanding the mechanisms that lead to the occurrence of sticking points as well as different training strategies that can be used to overcome them is important to strength practitioners (trainees and coaches alike) and instrumental for the avoidance of injury and continued progress. In this article we survey and consolidate the body of existing research on the topic: we discuss different definitions of the sticking point adopted in the literature and propose a more precise definition, describe different muscular and biomechanical aspects that give rise to sticking points, and review the effectiveness of different training modalities used to address them.
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The aim of this study was to investigate the existence of the sticking region in two legged free weight squats. Fifteen resistance‐training males (age 24 ± 4 years, body mass 82 ± 11 kg, body height 179 ± 6 cm) with 6 ± 3 years of resistance‐training experience performed 6‐RM in free weight squats. The last repetition was analyzed for the existence of a sticking region. Only in 10 out of 15 participants a sticking region was observed. The observed sticking region was much shorter than in the bench press. Furthermore, rectus femoris decreased the EMG activity in contrast to increased EMG activity in biceps femoris around the sticking and surrounding region. No significant change in EMG activity was found for the lateral and medial vastus muscles. It is suggested that a combination of these muscle activity changes could be one of the causes of the existence of the sticking region in free weight squats.
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Background: Although lower-body strength is correlated with sprint performance, whether increases in lower-body strength transfer positively to sprint performance remain unclear. Objectives: This meta-analysis determined whether increases in lower-body strength (measured with the free-weight back squat exercise) transfer positively to sprint performance, and identified the effects of various subject characteristics and resistance-training variables on the magnitude of sprint improvement. Methods: A computerized search was conducted in ADONIS, ERIC, SPORTDiscus, EBSCOhost, Google Scholar, MEDLINE and PubMed databases, and references of original studies and reviews were searched for further relevant studies. The analysis comprised 510 subjects and 85 effect sizes (ESs), nested with 26 experimental and 11 control groups and 15 studies. Results: There is a transfer between increases in lower-body strength and sprint performance as indicated by a very large significant correlation (r = -0.77; p = 0.0001) between squat strength ES and sprint ES. Additionally, the magnitude of sprint improvement is affected by the level of practice (p = 0.03) and body mass (r = 0.35; p = 0.011) of the subject, the frequency of resistance-training sessions per week (r = 0.50; p = 0.001) and the rest interval between sets of resistance-training exercises (r = -0.47; p ≤ 0.001). Conversely, the magnitude of sprint improvement is not affected by the athlete's age (p = 0.86) and height (p = 0.08), the resistance-training methods used through the training intervention, (p = 0.06), average load intensity [% of 1 repetition maximum (RM)] used during the resistance-training sessions (p = 0.34), training program duration (p = 0.16), number of exercises per session (p = 0.16), number of sets per exercise (p = 0.06) and number of repetitions per set (p = 0.48). Conclusions: Increases in lower-body strength transfer positively to sprint performance. The magnitude of sprint improvement is affected by numerous subject characteristics and resistance-training variables, but the large difference in number of ESs available should be taken into consideration. Overall, the reported improvement in sprint performance (sprint ES = -0.87, mean sprint improvement = 3.11 %) resulting from resistance training is of practical relevance for coaches and athletes in sport activities requiring high levels of speed.
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The purpose was to investigate the effect of 25 weeks heavy strength training in young elite cyclists. Nine cyclists performed endurance training and heavy strength training (ES) while seven cyclists performed endurance training only (E). ES, but not E, resulted in increases in isometric half squat performance, lean lower body mass, peak power output during Wingate test, peak aerobic power output (Wmax), power output at 4 mmol L−1 [la−], mean power output during 40-min all-out trial, and earlier occurrence of peak torque during the pedal stroke (P < 0.05). ES achieved superior improvements in Wmax and mean power output during 40-min all-out trial compared with E (P < 0.05). The improvement in 40-min all-out performance was associated with the change toward achieving peak torque earlier in the pedal stroke (r = 0.66, P < 0.01). Neither of the groups displayed alterations in VO2max or cycling economy. In conclusion, heavy strength training leads to improved cycling performance in elite cyclists as evidenced by a superior effect size of ES training vs E training on relative improvements in power output at 4 mmol L−1 [la−], peak power output during 30-s Wingate test, Wmax, and mean power output during 40-min all-out trial.
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