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Various training factors in combination with high intensity methodologies and techniques have been extensively investigated, with the intention of increasing anabolic, endocrine responses and subsequent structural adaptations. Variable resistance training allows the demands of an exercise to be matched to the muscle’s ability to exert force. The aim of this article is to examine whether variable resistance training produces significant gains in muscle mass compared to conventional resistance training.
Methods
A literature search was performed via PubMed, Web of Science, Cochrane and Scopus with search terms including “variable resistance”, “accommodating resistance”, “flywheel resistance”, “bands resistance”, “eccentric overloading resistance”, “isokinetic resistance”, “elastic resistance”, “variable cam”, “chain loaded resistance training”, “hypertrophy”, “resistance training”, strength training” and “power training” in July 2023. Inclusion criteria were studies that measured direct data related to muscle hypertrophy, compared variable resistance training and conventional resistance training and measured body composition using tape measures, ultrasound, dual-energy X-ray absorptiometry (DXA), magnetic resonance imaging and bioimpedance metres.
Results
Our search identified a total of 528 articles, and 12 studies met the inclusion criteria. The results of the studies analysed show that similar improvements occur, with no significant differences between the two training protocols.
Conclusion
This systematic review revealed that variable resistance training does not produce a greater gain in muscle mass compared to conventional training over a short–medium period of time and with untrained subjects. Therefore, it is necessary to compare these two training methods over longer training periods and with subjects with more experience in resistance training.
Miguel Angel Fuentes-García and Ewa Malchrowicz-Mośko contributed equally to this work.
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Introduction
Muscular strength is a physical capacity directly related to a large number of health parameters [1], such as a lower risk of coronary or cardiovascular disease, as well as to sporting performance in different sports [2]. In some sports, this performance is directly related to the amount of muscle mass, such as bodybuilding [2], or where hypertrophy becomes a differential factor, such as contact sports [3]. The main mechanisms for muscle mass development are mechanical strain, metabolic stress and muscle damage [2], which are achieved by training with loads mediated by the neuroendocrine system [4]. Other training variables influencing muscle mass gain, such as repetition range, volume, intensity, frequency and rest time have been extensively investigated [5]. However, regarding exercise selection, no extensive research has been conducted [5].
It is common to use free weights or machines for this purpose [6] in combination with training methodologies based on high intensity, making use of techniques such as rest-pause, drop sets, supersets or extreme stretching under load, amongst others. However, the mechanics involved in the use of free weights are sometimes problematic to achieve maximal effort throughout the active range of motion (ROM) of the joint [7]. Due to the body's leverage systems, the maximum weight that can be used during an exercise is limited by a phenomenon commonly known as sticking point, which creates a more disadvantageous position in ROM, limiting maximal external resistance [8]. If this sticking point could be minimised with more evenly distributed external resistance, it would allow for greater loading in higher leverage positions and, as a result, greater average muscle tension across the entire range of motion could be achieved and greater muscle mass gains could be made [2]. Variable resistance training (VRT) may, therefore, be useful to achieve this end.
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This method is based on a variation in the magnitude of resistance throughout the ROM of the exercise, altering the moment arm distance to provide greater resistance during certain phases of the ROM [7], giving the possibility of equalising the increases and decreases in muscle force (force curve) throughout the ROM [9]. This adaptation would allow a greater application of maximal force throughout the ROM by the muscles involved, thus being able to generate greater tension in each repetition and making training more efficient. The use of VRT has been shown to produce greater acute neural fatigue, higher total testosterone, growth hormone and cortisol compared to constant resistance training (CRT) [10], probably due to greater muscle activity [11]. Considering that adaptations occur in part due to fatigue of the neuromuscular system [12, 13], it is possible that the VRT has the potential to provide a greater stimulus in a smaller unit of training than a CRT. In this regard, studies have provided contradictory results. As we can see in a study proposed by Staniszewski et al. [14], they found significant differences in muscle mass gains using VRT for the elbow flexor musculature compared to CRT. However, other studies [15, 16] found no significant differences in measurements related to muscle hypertrophy.
Therefore, the aim of this systematic review is to observe whether VRT produces greater gains in muscle mass compared to CRT, as long as the rest of the variables remain stable throughout the programming (volume, intensity and duration of the training period).
Materials and methods
Literature search strategies
This article is a systematic review comparing VRT with CRT in terms of the hypertrophy potential that both provide.
A literature search of four databases was conducted in July 2023. The following databases were included: Pubmed, Cochrane, Web of Science and Scopus until July 2023. This ensured that adequate literature was obtained using high-quality databases, without including any language or year filters. The literature search was carried out using advanced searches with Title and Abstract (and keywords in the case of Cochrane and Scopus), which in combination with the Boolean operators resulted in the following search phrase: (“variable resistance” [Title/Abstract] OR “accommodating resistance” [Title/Abstract] OR “elastic resistance” [Title/Abstract] OR “variable cam” [Title/Abstract] OR “chain loaded resistance training” [Title/Abstract] OR “flywheel resistance” [Title/Abstract] OR “bands resistance” [Title/Abstract] OR “isokinetic resistance” [Title/Abstract] OR “eccentric overloading resistance” [Title/Abstract]) AND “hypertrophy” [Title/Abstract] AND (“resistance training” [Title/Abstract] OR “strength training” [Title/Abstract] OR “power training” [Title/Abstract]). In addition, articles found outside this search phrase and the databases were included by snowball effect. Relevant research was selected by screening the Titles and Abstracts of the databases used, and then reading the full articles to filter out those with potential for inclusion. These steps were done by two of the authors individually, and then discussed with a third.
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Inclusion and exclusion criteria
No filters for gender, race or level of participants were included to cover the maximum available literature due to the scarcity of the subject matter.
Studies were eligible for further analysis if they met the following inclusion criteria: (a) measured direct data related to muscle hypertrophy, (b) compared VRT and CRT interventions, (c) measured body composition using tape measures, ultrasound, dual-energy X-ray absorptiometry (DXA), magnetic resonance imaging and bioimpedance metres.
In terms of exclusion criteria, articles that did not meet the following criteria were rejected: (a) no older adults were involved (≥ 18), (b) no subjects with pathologies or injuries were involved. Figure 1 shows the flow chart of the search strategy.
In the present systematic review, 12 studies met the inclusion criteria, comparing 2 groups of individuals in which 1 group used VRT and the other followed CRT, usually with methodologies aimed at muscle mass gain. The main intention of this systematic review is to compare whether VRT produces greater structural adaptations in the musculoskeletal system.
Results
Mains search
Of the 528 articles found in the various databases with the search phrase, only 12 were included for the systematic review (Fig. 1). Of the 528 articles, 76 were excluded as duplicates. Of the remaining 450 articles, only 91 fulfilled the inclusion and exclusion criteria for the systematic review. Of the 91, 79 were dismissed after looking at the Title or Abstract for including subjects with pathologies (n = 36), older adults (n = 9), not measuring hypertrophy (n = 11), does not compare training methods (n = 23) other reasons (n = 4). Therefore, this systematic review includes 12 studies [6, 14, 16‐25].
The effect of variable resistance on muscle hypertrophy
The characteristics of the participants, the variables measured and the protocols used in the different studies are shown in Table 1.
Table 1
Characteristics of the subjects and instruments used
Table 2 shows the results of the studies included in this review, which included subjects in the following categories: physical education students (n = 2), professional handball players (n = 1), trained athletes (n = 1), people with previous experience in resistance training (n = 1) and people with no sporting experience in the last months (n = 7). The exercises to be compared generally involved a single joint such as the elbow (n = 4) or knee (n = 8). In addition, there were studies in which other exercises were included in the programme involving the muscle groups to be analysed apart from the exercises being compared (n = 4).
Table 2
Summary of studies included in the systematic review
28 healthy young men. Subjects had previous resistance training experience (21 + 3). AEL age 21 ± 2 years TRAD (age 21 ± 2 years, CON (age 24 ± 2 years)
Bilateral leg press and unilateral knee flexion and extension exercises
TRAD performed the exercises with the same load for the concentric and eccentric phases, whilst AEL performed the exercises with 40% more load during the eccentric phase compared to the concentric phase
3 × 6-RM Session 1/3 × 10-RM (session 2) tempo 2:2 s (4 s)
Flywheel knee extension Traditional weight stack knee extension
7 × 4/2′ flywheel
8–12 × 4/2′ weight stack
Measured cross-sectional area of LV, MV and RF, LV. It was evaluated at a proximal and distal site
↔
(8% FW and 9%WS)
Discussion
The intention of this systematic review is to look at the differences in muscle mass gain when using exercises with a resistance profile adapted to the muscle's capacity to exert force compared to conventional resistance training. The results of the studies included in this review indicate that there are no significant differences between the two training protocols. For this reason, with the current evidence, it is not possible to state that the use of variable resistance is superior in generating structural adaptations. However, despite not finding significant improvements in the adaptations produced by variable resistance training, it is interesting to note the possible trend towards improvement recorded in many of the articles used for this systematic review.
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On the one hand, as far as the methodologies used are concerned, the duration of most of the studies may not be sufficient to see the differences in structural adaptations between the two training methods, as it has been shown that during the first weeks, the adaptations to resistance training are mainly neural, whilst morphological changes occur later [26‐28]. These neural adaptations may occur especially in the case of subjects who are not used to strength training [29], that is, the majority of the participants in these studies, so that morphological changes are more complex to obtain. Furthermore, according to findings by Pipes [29], they suggest that, in subjects who are not accustomed to strength training, variable resistance devices may not provide more benefits than those achieved by initiating a systematic strength training programme. Knowing that the response to training is, amongst other factors, dependent on the level of the subject [2, 4], it is possible that in these subjects, it does not provide an extra stimulus by adapting the load distribution.
On the other hand, it is conceivable that as far as muscle activity is concerned, the change in load distribution provided by the variable resistance altered muscle recruitment patterns [3]. This should keep the muscle working closer to its maximal capacity at all ROM by reducing the stagnation point, which could have led to greater recruitment of type IIX fibres [15] and hence greater adaptations of these fibres. During the movement of an exercise, the bar is accelerated up to this stagnation point which, once overcome, the force required to complete the muscle contraction becomes submaximal [8]. Thus, overcoming this stagnation point by means of different variable resistance techniques (specific machines, rubber bands, chains…) would allow a uniform intensity to be applied throughout the ROM, making it possible to squeeze every part of it and achieve a much more efficient stimulus when it comes to producing gains in muscle mass [3].
Furthermore, in the study proposed by Staniszewski et al. [14], a decrease in bicipital and tricipital skinfolds was obtained after only 4 weeks of training, without significant changes in arm circumferences. It is possible to assume that these changes are due to some gain in muscle mass [30]. In other studies, in which no differences were seen between the two types of exercise, it is possible to deduce that similar internal physiological stress may have been produced by different means: on the one hand, in the preacher curl with pulley, training at longer muscle lengths produces more interactions between actin and myosin filaments [31, 32], which would produce greater mechanical tension and, therefore, greater muscle growth. On the other hand, the barbell preacher curl works at shorter muscle lengths, which can lead to greater metabolic stress and also increase mechanical stress [33]. Thus, the balance between lower and higher torque in the different phases of the movement and between mechanical and metabolic stress, which are important factors, amongst others, for muscle growth [2], may explain the similarity of the results between variable resistance and constant resistance.
When looking at the case of the quadriceps muscles analysed by Norrbrand et al. [22], it is possible to see how with constant resistance training, only the size of the rectus femoris increased, whilst with variable resistance training, all muscle bellies improved. Surprisingly, even though these differences were not statistically significant, the growth of the subjects who used variable resistance was more than double that of those who used a plate machine (6.2% vs. 3%). This could indicate a much greater difference if the training sessions were of longer duration. This could imply a greater performance in the different sports modalities and a greater hormonal response.
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In terms of hormonal responses, different responses were found in the two types of training [34]. After 8 weeks, analysis of the different hormonal parameters shows that, with the exception of growth hormone (GH), the adapted endurance group had a greater hormonal change despite not having statistically significant differences: a greater increase in IGF-1 and follistatin and a decrease in myostatin and cortisol. IGF-1 is one of the most studied anabolic hormones along with GH [35], whilst cortisol and myostatin have a mostly catabolic function through protein degradation [35, 36]. Follistatin, on the other hand, is a myostatin inhibitor [36], so it also exerts an anti-catabolic role. Considering these changes and hormonal differences, it is possible to predict an increase in muscle mass and strength [37], possibly to a greater extent in the adapted endurance group in the long term.
Despite the above, little is known about the heterogeneity of hormonal responses to strength training [34]. However, according to Bouchard and Rankinen [38], there is a link between genetic variations and skeletal muscle characteristics such as muscle fibre composition that could affect adaptations to training [39]. Taking into account hormonal changes at rest to a more anabolic state, improvements in muscle mass and strength would be expected [37]. Accordingly, the findings of Arazi et al. [34] indicated that there were significant correlations between FFM with anabolic and catabolic hormones and myokines including IGF-1, cortisol, myostatin, and phylostatin, which would predict an increase in muscle mass and strength, possibly occurring to a greater extent with long-term variable resistance training.
All training groups demonstrated a similar time course of changes in creatine kinase (CK) activity [6, 23]. However, hypertrophy training using variable resistance was a less strenuous stimulus for inducing muscle damage than the use of a machine with a disc plate. It can, therefore, be concluded that in strength training methods that require a higher number of repetitions in sets, it is more effective to train on a machine with variable resistance. Taking into account the findings of the work of Damas et al. [40] in which it was seen that protocols with less muscle damage achieved similar hypertrophy to those that did, it may be that this method is less harmful and more efficient [6] to achieve this objective, although we cannot find a conclusive conclusion.
In all the studies analysed, there are several limitations that do not allow a conclusive conclusion to be drawn, due to the fact that, on the one hand, the level of the participants is, in most of them, that of beginners with no previous experience. This means that it is not possible to extrapolate the results obtained to the rest of the population, since the response to training is, amongst other factors, dependent on the level of the subject [2, 4], so it is possible that, in this type of subject, adapting the endurance profile does not promote extra gains compared to not doing so.
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Conclusion
The use of a conventional resistance causes muscles to work at maximum load over only a portion of the entire range of motion. However, the use of a variable resistance allows the external load to be adjusted to a muscle's ability to exert force throughout the entire range of motion. This allows for greater efficiency, comfort and safety for the athlete. However, although the results have been superior for variable resistance in terms of muscle mass gain in the different studies, they have not been significantly so in the short–medium term (8 weeks) and with untrained subjects. Therefore, research is needed to compare variable and conventional resistance over longer periods of training and with subjects with more experience in resistance training.
Practical applications
Muscle strength training is widely used as a primary or supplemental training method to increase muscle size and strength in most sports disciplines [6]. Therefore, any performance support in this regard should be taken into account when developing a training programme. The use of variable resistance allows the load to be adjusted to the muscle's ability to exert force over the full range of motion [3], allowing for greater efficiency, comfort and safety for the athlete [6]. After having analysed the current evidence of this training methodology, it is worth mentioning that the use of variable resistance training is as effective a training method as conventional resistance training. In addition, it is possible that this method could be interesting to apply it in those sports where muscle mass is a differential factor, such as bodybuilding [2], because in some of the articles observed, it has been seen that variable resistance training, without significant difference, produces a slightly greater hypertrophy compared to conventional training [14, 16, 22, 23].
However, there are some variables that may influence the subject’s response to improve performance in variable resistance training: sex, age, experience in resistance training, inclusion of other exercises (in addition to those we want to investigate), physical fitness, duration of training. Therefore, we believe that it would be convenient to continue investigating the effect of accommodating the resistance profile compared to not doing it, although taking into account these variables.
Declarations
Conflict of interest
Miguel Angel Fuentes-García, Ewa Malchrowicz-Mośko and Arkaitz Castañeda-Babarro have nothing to disclose.
Ethical approval
This project is a systematic review, and thus ethics approval is not applicable.
Consent to participate
Not applicable to this systematic review.
Consent for publishing
Not applicable to this systematic review.
Informed consent
Since this is a systematic review, there is no informed consent.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.
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Silventoinen K, Magnusson PK, Tynelius P, Batty GD, Rasmussen F (2009) Association of body size and muscle strength with incidence of coronary heart disease and cerebrovascular diseases: a population-based cohort study of one million Swedish men. Int J Epidemiol 38(1):110–118. https://doi.org/10.1093/ije/dyn231CrossRefPubMed
Andersen V, Pedersen H, Fimland MS, Shaw MP, Solstad TEJ, Stien N, Cumming KT, Saeterbakken AH (2021) Acute effects of elastic bands as resistance or assistance on EMG, kinetics, and kinematics during deadlift in resistance-trained men. Front Sports Active Living. https://doi.org/10.3389/fspor.2020.598284CrossRef
4.
Kraemer WJ, Ratamess NA, Komi P (2003) Endocrine responses and adaptations to strength and power training. Strength Power Sport 2:361–386CrossRef
Staniszewski M, Mastalerz A, Urbanik C (2020) Effect of a strength or hypertrophy training protocol, each performed using two different modes of resistance, on biomechanical, biochemical and anthropometric parameters. Biol Sport 37(1):85–91. https://doi.org/10.5114/biolsport.2020.92517CrossRefPubMedPubMedCentral
Elliott BC, Wilson GJ, Kerr GK (1989) A biomechanical analysis of the sticking region in the bench press. Med Sci Sports Exerc 21(4):450–462CrossRefPubMed
9.
Fleck SJ, Kraemer W (2014) Designing resistance training programs, 4th edn. Human Kinetics, ChampaignCrossRef
Campos GE, Luecke TJ, Wendeln HK, Toma K, Hagerman FC, Murray TF, Ragg KE, Ratamess NA, Kraemer WJ, Staron RS (2002) Muscular adaptations in response to three different resistance-training regimens: specificity of repetition maximum training zones. Eur J Appl Physiol 88(1–2):50–60. https://doi.org/10.1007/s00421-002-0681-6CrossRefPubMed
13.
Mohr M, Krustrup P, Nielsen JJ, Nybo L, Rasmussen MK, Juel C, Bangsbo J (2007) Effect of two different intense training regimens on skeletal muscle ion transport proteins and fatigue development. Am J Physiol Regul Integr Comp Physiol 292(4):R1594–R1602. https://doi.org/10.1152/ajpregu.00251.2006CrossRefPubMed
14.
Staniszewski M, Urbanik C, Mastalerz A, Lutoslawska G, Iwanska D, Madej A, Karczewska M, Tkaczyk J (2015) Use of a variable-cam for strength training of the elbow flexors. Isokinet Exerc Sci 23(3):161–168CrossRef
Nunes JP, Jacinto JL, Ribeiro AS, Mayhew JL, Nakamura M, Capel DMG, Santos LR, Santos L, Cyrino ES, Aguiar AF (2020) Placing greater torque at shorter or longer muscle lenghts? Effects of cable vs barbell preacher curl training on muscular strength and hypertrophy in young adults. Int J Environ Res Public Health. https://doi.org/10.3390/ijerph17165859CrossRefPubMedPubMedCentral
17.
Friedmann-Bette B, Bauer T, Kinscherf R, Vorwald S, Klute K, Bischoff D, Müller H, Weber MA, Metz J, Kauezor HU, Bärtsch P, Billeter R (2010) Effects of strength training with eccentric overload on muscle adaptation in male athletes. Eur J Appl Physiol 108:821–836. https://doi.org/10.1007/s00421-009-1292-2CrossRefPubMed
18.
Lundberg TR, García-Gutiérrez MT, Mandić M, Lilja M, Fernandez-Gonzalo R (2019) Regional and muscle specific adaptations in knee extensor hypertrophy using flywheel versus conventional weight-stack resistance exercise. Appl Physiol Nutr Metab 44(8):827–833. https://doi.org/10.1139/apnm-2018-0774CrossRefPubMed
19.
Maroto-Izquierdo S, García-López D, de Paz JA (2017) Functional and muscle size effects of flywheel resistance training with eccentric-overload in professional handball players. J Hum Kinet 60(133):143. https://doi.org/10.1515/hukin-2017-0096CrossRef
20.
Matta TT, Nascimento FXMB, Fernandes IA, Oliveira LF (2015) Heterogeneity of rectus femoris muscle architectural adaptations after two different 14-week resistance training programmes. Clin Physiol Funct Imaging 35(3):210–215. https://doi.org/10.1111/cpf.12151CrossRefPubMed
21.
Matta TT, Nascimento FX, Trajano GS, Simao R, Willardson JM, Oliveira LF (2015) Selective hypertrophy of the quadriceps musculature after 14 weeks of isokinetic and contional resistance training. Clin Physiol Funct Imaging 37(2):137–142. https://doi.org/10.1111/cpf.12277CrossRefPubMed
22.
Norrbrand L, Fluckey JD, Pozzo M, Tesch PA (2008) Resistance training using eccentric overload induces early adaptations in skeletal muscle size. Eur J Appl Physiol 102(3):271–281. https://doi.org/10.1007/s00421-007-0583-8CrossRefPubMed
23.
Urbanik C, Staniszewski M, Mastalerz A, Karczewska M, Lutosławska G, Iwańska D, Madej A, Ostrowska E, Gwarek L, Tkaczyk J (2013) Evaluation of the effectiveness of training on a machine with a variable-cam. Acta Bioeng Biomech 15(4):93–102PubMed
24.
Walker S, Blazevich AJ, Haff GG, Tufano JJ, Newton RU, Häkkinen K (2016) Greater strength gains after training with accentuated eccentric than traditional isoinertial loads in already strength-trained men. Front Physiol 7:149. https://doi.org/10.3389/fphys.2016.00149CrossRefPubMedPubMedCentral
25.
Walker S, Hulmi JJ, Wernbom M, Nyman K, Kraemer WJ, Ahtiainen JP, Häkkinen K (2013) Variable resistance training promotes greater fatigue resistance but not hypertrophy versus constant resistance training. Eur J Appl Physiol 113(9):2233–2244. https://doi.org/10.1007/s00421-013-2653-4CrossRefPubMed
26.
De Lemos Muller CH, Remis TR, Ribeiro JL (2015) Comparison of the effects of resistance training with and without vascular occlusion in increases of strength and hypertrophy: a review of the literature. Sports Med 11(4):2668–2675
27.
Mangine GT, Hoffman JR, Gonzalez AM, Townsend JR, Wells AJ, Jajtner AR, Beyer KS, Boone CH, Miramonti AA, Wang R, LaMonica MB, Fukuda DH, Ratamess NA, Stout JR (2015) The effect of training volume and intensity on improvements in muscular strength and size in resistance-trained men. Physiol Rep 3(8):e12472. https://doi.org/10.14814/phy2.12472CrossRefPubMedPubMedCentral
Lowery RP, Joy JM, Loenneke JP, de Souza EO, Machado M, Dudeck JE, Wilson JM (2014) Practical blood flow restriction training increases muscle hypertrophy during a periodized resistance training programme. Clin Physiol Funct Imaging 34(4):317–321. https://doi.org/10.1111/cpf.12099CrossRefPubMed
31.
McMahon GE, Morse CI, Burden A, Winwood K, Onambélé GL (2014) Impact of range of motion during ecologically valid resistance training protocols on muscle size, subcutaneous fat, and strength. J Strength Cond Res 28(1):245–255. https://doi.org/10.1519/JSC.0b013e318297143aCrossRefPubMed
32.
Oranchuk DJ, Storey AG, Nelson AR, Cronin JB (2019) Isometric training and long-term adaptations: effects of muscle length, intensity, and intent: a systematic review. Scand J Med Sci Sports 29(4):484–503. https://doi.org/10.1111/sms.13375CrossRefPubMed
33.
Goto M, Maeda C, Hirayama T, Terada S, Nirengi S, Kurosawa Y, Nagano A, Hamaoka T (2019) Partial range of motion exercise is effective for facilitating muscle hypertrophy and function through sustained intramuscular hypoxia in young trained men. J Strength Cond Res 33(5):1286–1294. https://doi.org/10.1519/JSC.0000000000002051CrossRefPubMed
34.
Arazi H, Salek L, Nifkal E, Izadi M, Tufano JJ, Elliot BT, Brughelli M (2020) Comparable endocrine and neuromuscular adaptations to variable vs. constant gravity-dependent resistance training among young women. J Trasl Med. https://doi.org/10.1186/s12967-020-02411-yCrossRef
Mulligan SE, Fleck SJ, Gordon SE, Koziris LP, Triplett-McBride NT, Kraemer WJ (1996) Influence of resistance exercise volume on serum growth hormone and cortisol concentrations in women. J Strength Cond Res 10(4):256–262
Damas F, Libardi CA, Ugrinowitsch C (2018) The development of skeletal muscle hypertrophy through resistance training: the role of muscle damage and muscle protein synthesis. Eur J Appl Physiol 118(3):485–500. https://doi.org/10.1007/s00421-017-3792-9CrossRefPubMed
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