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Abstract

The choice of the optimal squatting depth for resistance training (RT) has been a matter of debate for decades and is still controversial. In this study, fifty-three resistance-trained men were randomly assigned to one of four training groups: full squat (F-SQ), parallel squat (P-SQ), half squat (H-SQ), and Control (training cessation). Experimental groups completed a 10-week velocity-based RT programme using the same relative load (linear periodization from 60% to 80% 1RM), only differing in the depth of the squat trained. The individual range of motion and spinal curvatures for each squat variation were determined in the familiarization and subsequently replicated in every lift during the training and testing sessions. Neuromuscular adaptations were evaluated by one-repetition maximum strength (1RM) and mean propulsive velocity (MPV) at each squatting depth. Functional performance was assessed by countermovement jump, 20-m sprint and Wingate tests. Physical functional disability included pain and stiffness records. F-SQ was the only group that increased 1RM and MPV in the three squat variations (ES = 0.77–2.36), and achieved the highest functional performance (ES = 0.35–0.85). P-SQ group obtained the second best results (ES = 0.15–0.56). H-SQ produced no increments in neuromuscular and functional performance (ES = −0.11–0.28) and was the only group reporting significant increases in pain, stiffness and physical functional disability (ES = 1.21–0.87). Controls declined on all tests (ES = 0.02–1.32). We recommend using F-SQ or P-SQ exercises to improve strength and functional performance in well-trained athletes. In turn, the use of H-SQ is inadvisable due to the limited performance improvements and the increments in pain and discomfort after continued training.
ORIGINAL ARTICLE
Full squat produces greater neuromuscular and functional adaptations
and lower pain than partial squats after prolonged resistance training
JESÚS G. PALLARÉS
1
, ALEJANDRO M. CAVA
1
, JAVIER COUREL-IBÁÑEZ
1
,
JUAN JOSÉ GONZÁLEZ-BADILLO
2
, & RICARDO MORÁN-NAVARRO
1
1
Faculty of Sport Sciences, Human Performance and Sports Science Laboratory, University of Murcia, Murcia, Spain &
2
Faculty of Sport, Pablo de Olavide University, Seville, Spain
Abstract
The choice of the optimal squatting depth for resistance training (RT) has been a matter of debate for decades and is still
controversial. In this study, fifty-three resistance-trained men were randomly assigned to one of four training groups: full
squat (F-SQ), parallel squat (P-SQ), half squat (H-SQ), and Control (training cessation). Experimental groups completed
a 10-week velocity-based RT programme using the same relative load (linear periodization from 60% to 80% 1RM), only
differing in the depth of the squat trained. The individual range of motion and spinal curvatures for each squat variation
were determined in the familiarization and subsequently replicated in every lift during the training and testing sessions.
Neuromuscular adaptations were evaluated by one-repetition maximum strength (1RM) and mean propulsive velocity
(MPV) at each squatting depth. Functional performance was assessed by countermovement jump, 20-m sprint and
Wingate tests. Physical functional disability included pain and stiffness records. F-SQ was the only group that increased
1RM and MPV in the three squat variations (ES = 0.772.36), and achieved the highest functional performance (ES =
0.350.85). P-SQ group obtained the second best results (ES = 0.150.56). H-SQ produced no increments in
neuromuscular and functional performance (ES = 0.110.28) and was the only group reporting significant increases in
pain, stiffness and physical functional disability (ES = 1.210.87). Controls declined on all tests (ES = 0.021.32). We
recommend using F-SQ or P-SQ exercises to improve strength and functional performance in well-trained athletes. In
turn, the use of H-SQ is inadvisable due to the limited performance improvements and the increments in pain and
discomfort after continued training.
Keywords: Muscle strength,velocity-based resistance training,propulsive phase,lumbar spine
Highlights
.Training at F-SQ produced the greatest improvements in all neuromuscular performance parameters for the three
squatting depths. In contrast, intervention with H-SQ produced the worst results.
.Whereas individuals improved more at the specific depth at which they trained, results from the F-SQ group were still the
best.
.The three groups reported a moderate rise in pain perception scores following the 10-week RT program, but the H-SQ
experienced an acute increase in pain, stiffness and physical functional disability indexes.
.According to these findings, we conclude that F-SQ and P-SQ are the safest and most effective squat exercises to improve
strength and functional performance, while H-SQ is unadvisable given the limited benefits and high discomfort.
Introduction
The back squat (SQ) is one of the most widely used
and effective resistance training (RT) exercises for
strengthening the lower-limb, protecting against inju-
ries and improving athletic performance (Hartmann,
Wirth, & Klusemann, 2013). In the last three
decades, numerous publications have found that
increases in lower-body strength following SQ train-
ing transfer positively to functional athletic perform-
ance in short-duration actions that demand
maximal voluntary contractions, such as sprinting
and vertical jumping (Hartmann et al., 2012; Seitz,
Reyes, Tran, de Villarreal, & Haff, 2014; Suchomel,
Nimphius, & Stone, 2016; Wirth et al., 2016).
© 2019 European College of Sport Science
Correspondence: Jesús García Pallarés, Faculty of Sport Sciences, Human Performance and Sports Science Laboratory, University of
Murcia, C/ Argentina s/n. Santiago de la Ribera, Murcia, Spain. E-mail: jgpallares@um.es
European Journal of Sport Science, 2019
https://doi.org/10.1080/17461391.2019.1612952
... An important factor determining the gain in sprinting performance seems to be squat depth, which we classified in accordance with Hartmann et al., 35 meaning deep squat as 40°-45°, half squat as 80°-100°, and quarter squat as 110°-140°of knee extension. Studies have shown that deep barbell front and back squats yield superior results 35,37 while quarter und half squats simultaneously pose higher risks of injury. 35,[37][38][39] The transfer of high-load strength training to sports-specific motions is achieved through technique and plyometric training. ...
... Studies have shown that deep barbell front and back squats yield superior results 35,37 while quarter und half squats simultaneously pose higher risks of injury. 35,[37][38][39] The transfer of high-load strength training to sports-specific motions is achieved through technique and plyometric training. 17,[40][41][42] Therefore, it is recommended that both junior and senior soccer players make use of deep squats instead of half or quarter squats and combine these with sprint technique and plyometric training to maximize sprinting performance. ...
... players. Based on the findings of Hartmann et al. 35 as well as Pallarés et al., 37 future studies should make use of deep squats instead of half squats. Furthermore, more research on long-term strength training effects would be desirable. ...
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Practical Question: Is high-load squat training beneficial in improving sprinting performance in junior elite-level soccer players? Clinical Bottom Line: There is Level 3 evidence to support the validity of high-load squat training as a measure to improve sprinting performance in junior male elite-level soccer players. All three studies included showed significant increases in soccer-related sprinting performance.
... However, after evaluating the abstracts, full-texts, and analyzing the strict fulfillment of the other inclusion criteria, 236 articles were excluded. A total of 22 studies met the pre-established requirements [22,29,30,[38][39][40][52][53][54][55][56][57][58][59][60][61][62][63][64][65][66][67]. Considering that the present systematic review is reported according to the parameters established in the PRISMA guidelines, a flow chart of the literature search is shown in Figure 1. ...
... Notwithstanding, most of the studies revealed greater improvements in 1-RM after a VBRT program when compared to PBT (Table 1). Regarding to exercise technique, Pallares et al. [63] evaluated three different positions of the squat exercise: full squat, parallel squat, and half squat. This study showed statistically significant effects in full and parallel squat, but not in half squat. ...
... Fifteen studies have investigated the effect of VBRT on running sprinting (10-30 m) with a total of 406 strength-trained subjects [22,29,30,[38][39][40]52,55,57,59,60,63,64,66,67]. However, only eight studies [29,30,39,55,59,60,66,67] concluded that VBRT has positive or superior effects to other strategies, while the other studies did not report improvements with respect to the control group. ...
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Weight resistance training (RT) has been shown to positively influence physical performance. Within the last two decades, a methodology based on monitoring RT through movement velocity (also called velocity-based resistance training, VBRT) has emerged. The aim of this PRISMA-based systematic review was to evaluate the effect of VBRT programs on variables related to muscle strength (one-repetition maximum, 1-RM), and high-speed actions (vertical jump, and sprint performance) in trained subjects. The search for published articles was performed in PubMed/MEDLINE, SPORT Discus/EBSCO, OVID, Web of Science, Scopus, and EMBASE databases using Boolean algorithms independently. A total of 22 studies met the inclusion criteria of this systematic review (a low-to-moderate overall risk of bias of the analyzed studies was detected). VBRT is an effective method to improve 1-RM, vertical jump and sprint. According to the results of the analyzed studies, it is not necessary to reach high muscle failure in order to achieve the best training results. These findings reinforce the fact that it is possible to optimize exercise adaptations with less fatigue. Future studies should corroborate these findings in female population.
... 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. ...
... 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. Similarly, a study by Martínez-Cava et al. 11 showed that 10 weeks of full ROM bench press exercises led to greater improvements in maximum strength compared to the partial ROM bench press. ...
... 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
... After the full-text screening, 16 studies were considered for qualitative analysis and meta-analyses. [53][54][55][56][57][58][59][60][61][62][63][64][65][66][67][68] Two authors provided missing data not published in the original studies. 54,60 ...
... 72,73 Therefore, the fact that partial repetitions systematically avoid this zone of maximal active tension could be the reason behind the lower effectiveness of partial ROM in enhancing strength. 59,63 However, future research is needed to understand the kinematics and physiological mechanisms that underlie these findings. On the contrary, the lack of studies executing the partial ROM training at long muscle lengths limited the current research to examine whether there are differences between full and partial ROMs according to the muscle length trained by the latter. ...
... 56,61,66,67 Conversely, other investigations showed that, although each training group maximized the strength gains at the specific ROM they trained, the full ROM group obtained the greatest neuromuscular improvements even in the partial tests. 59,63 It should be taken into account that the specificity principle could be related to the learning effect of participants, after regular practice. For example, a participant who trained during weeks at a given ROM is expected to obtain greater post-intervention performance in this specific ROM as a consequence of the familiarization with the execution of the exercise. ...
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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.
... 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). Briefly, the L-V relationship involves practitioners establishing a target mean propulsive velocity (MPV, mean velocity from the propulsive phase, defined as that portion of the concentric phase during which barbell acceleration [a] is greater than the acceleration because of gravity [a $ 29.81 m$s 22 ]) (48) to be attained in the fastest repetition (usually the first) of each training session. ...
... In addition to incorporating sportspecific evaluations like sprints or jumps, the limitation of the traditional 1RM test to evaluate performance changes against light-moderate loads can be overcome by measuring pretraining-posttraining changes in barbell velocity. Specifically, considering that the only way to achieve a higher barbell velocity against the same absolute load (in kilograms) is to exert more force (if the execution technique has remained identical) (2), practitioners could add the barbell velocity to their testing routine to evaluate the changes in dynamic strength across the entire spectrum of loads (27,35,39,44,46). Furthermore, practitioners could estimate the "strength deficit" using the L-V relationship. ...
... O exercício de agachamento é amplamente utilizado entre os praticantes de musculação, sendo um dos mais eficientes para a hipertrofia nos membros inferiores (3,4) . Este exercício tradicional é uma combinação de movimentos que ocorrem simultaneamente mediante a extensão de quadril e de joelho, tendo a sobrecarga posicionada na porção superior posterior do dorso (tórax), geralmente sobre o músculo trapézio descendente (4)(5)(6) . ...
... O exercício de agachamento é amplamente utilizado entre os praticantes de musculação, sendo um dos mais eficientes para a hipertrofia nos membros inferiores (3,4) . Este exercício tradicional é uma combinação de movimentos que ocorrem simultaneamente mediante a extensão de quadril e de joelho, tendo a sobrecarga posicionada na porção superior posterior do dorso (tórax), geralmente sobre o músculo trapézio descendente (4)(5)(6) . ...
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... Resistance training (RT) has been proven as an effective strategy to increase athletic performance [1,2] and health status [3,4]. However, adaptations in response to a given RT program mainly depend on the manipulation of different variables such as the relative intensity [5,6], exercises trained [7], training frequency [8,9], volume [10], or range of motion used [11,12]. In addition to these parameters, effects generated by resistance exercises are modulated by the level of fatigue generated within each training set (i.e., intra-set fatigue). ...
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... 9 17-19 In addition to the particularities among training disciplines, new trends in sport sciences appeal to more individualised regimens with a variety of exercises, stimuli and intensities which are controlled by incorporating new technologies and monitoring tools. [20][21][22][23][24][25] When people stop exercising regularly or there is an insufficient training stimulus, they may suffer a partial or complete loss of training-induced adaptations, namely the detraining effect. 26 While older adults commonly suffer from hospitalisation, illness or immobilisation that temporarily disrupt any physical activity, 27 prior studies have demonstrated that benefits of exercise may persist after short-term 28 29 and even long-term 30-32 exercise cessation in community-dwelling. ...
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Introduction There is not a doubt that tailored exercise is an effective non-pharmacological approach for preventing, mitigating and even reversing ageing-related alterations. However, older adults are likely to experience prolonged periods of inactivity and training cessation periods as a consequence of falls or hospitalisation. Although recent evidence supports that exercise could have a protective effect and help in recovering, there is to date a lack of consensus about what kind of physical exercise prescription and training duration would produce better outcomes after training cessation periods. The current study will determine the effects that available exercise prescriptions produced in older adults in preserving physical conditioning following inactivity periods. Methods and analysis A systematic search of the literature will be conducted in three databases, namely PubMed, Scopus and Web of Science, from inception to 1 February 2021. Only randomised controlled trials written in English or Spanish will be eligible. No year of publication restriction will be applied. Eligible studies will contain information on population (older adults over 60 years old), intervention (inactivity period, exercise programme their duration), comparator (treatment as usual or waiting list) and outcomes (strength, functional capacity, metabolic health and skeletal muscle structure). Two independent reviewers will (1) search, screen and select studies, (2) extract data about their main characteristics and (3) evaluate their methodological and reporting quality. When disagreements emerge, the reviewers will discuss to reach a consensus. We plan to conduct meta-analysis to quantitatively synthesise the effects under study. Ethics and dissemination As systematic reviews use publicly available data, no formal ethical review and approval are needed. Findings will be published in a peer-reviewed journal(s) and presented at conferences. PROSPERO registration number CRD42021235092.
... In addition, partial ROM allows lifting higher loads in comparison with full ROM, which results in substantially greater force production (Clark et al., 2008). However, a greater ROM allows for a higher velocity of movement (Drinkwater et al., 2012;, and recently conducted studies have found that full ROMs after resistance training produces greater neuromuscular adaptations than partial movements (Martínez-Cava, Hernández-Belmonte, et al., 2019;Pallarés et al., 2020). Therefore, the optimal ROM is still a matter of debate in the fitness society (Goto et al., 2019). ...
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Chapter
We propose a safe design of squat exergame to maintain lower extremity strength that includes Dynamic Difficulty Adjustment (DDA). This is to optimise the game difficulty according to a Knee Shakiness (KS) parameter. We modulated two parameters to implement DDA namely, movement speed and Pneumatic Gel Muscle (PGM)-based assistance. The movement speed of the user relates to the frequency of squatting, and the PGM-based assistance was provided by pneumatic actuators called PGMs attached on the hip and knee joints of the lower extremity. We provided variable PGM-based assistance during the onset phase of the squat and a fixed PGM-based resistance during the end phase of the squat. We used collectible spherical objects in the exergame to maintain a good squat posture. The squat posture parameters, knee distance and squat depth showed improvement through the proposed design. Introducing DDA could also significantly reduce KS during the squats.
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