==== Front J Funct Morphol Kinesiol J Funct Morphol Kinesiol jfmk Journal of Functional Morphology and Kinesiology 2411-5142 MDPI 10.3390/jfmk5020025 jfmk-05-00025 Editorial The “Journal of Functional Morphology and Kinesiology” Journal Club Series: Resistance Training https://orcid.org/0000-0003-0474-4229Paoli Antonio 1 https://orcid.org/0000-0002-1404-1511Moro Tatiana 1 Lorenzetti Silvio 2 Seiler Jan 2 Lüthy Fabian 2 Gross Micah 2 Roggio Federico 3 https://orcid.org/0000-0001-7812-7931Chaabene Helmi 4 https://orcid.org/0000-0002-8260-8890Musumeci Giuseppe 356* 1 Department of Biomedical Sciences, University of Padova, 35131 Padova, Italy 2 Swiss Federal Institute of Sport Magglingen (SFISM), 2532 Magglingen, Switzerland 3 Department of Biomedical and Biotechnological Sciences, Anatomy, Histology and Movement Sciences Section, School of Medicine, University of Catania, Via S. Sofia 87, 95123 Catania, Italy 4 Division of Training and Movement Sciences, University of Potsdam, Am Neuen Palais 10, 14469 Potsdam, Germany 5 Research Center on Motor Activities (CRAM), University of Catania, 95123 Catania, Italy 6 Department of Biology, Sbarro Institute for Cancer Research and Molecular Medicine, College of Science and Technology, Temple University, Philadelphia, PA 19122, USA * Correspondence: g.musumeci@unict.it; Tel.: +39-095-378-2043 02 4 2020 6 2020 5 2 2525 3 2020 26 3 2020 © 2020 by the authors.2020Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (http://creativecommons.org/licenses/by/4.0/).We are glad to introduce the Second Journal Club of Volume Five, Second Issue. This edition is focused on relevant studies published in the last few years in the field of resistance training, chosen by our Editorial Board members and their colleagues. We hope to stimulate your curiosity in this field and to share with you the passion for the sport, seen also from the scientific point of view. The Editorial Board members wish you an inspiring lecture. ==== Body 1. Introduction Resistance training, also known as strength training, is a form of exercise that improves muscular strength and endurance [1,2,3]. During a resistance training workout, limbs move against resistance provided by your body weight, gravity, bands, weighted bars, or dumbbells. Some exercise machines can also be used for resistance training. Any exercise where the body moves against resistance can be considered resistance or strength training [1,2,3]. The definition of resistance in this form of training is simple as well. Resistance is any force that makes the movement harder to perform. Resistance can be provided simply by moving your body against gravity; by adding weighted dumbbells or using machines at the gym; or by using equipment such as weighted bars, bands, or kettlebells [1,2,3]. This form of training can also be called weight lifting or weight training. The benefits of resistance training are significant for skeletal muscle mass mutation [4,5,6]. Skeletal muscle is a particular tissue that modifies its general functional ability in reaction to varied stimuli [4,5,6]. Strength improvement, as well as increases in muscle cross-sectional area and contractile capacity, noted during the initial phase of training would result from neuromuscular activation in combination with trophic factors [4,5,6]. In order to stimulate further adaptation toward specific training goals, progressive resistance training (RT) protocols are necessary [7]. The optimal characteristics of strength-specific programs include the use of concentric (CON), eccentric (ECC), and isometric muscle actions, and the performance of bilateral and unilateral single- and multiple-joint exercises [7]. Strength programs sequence exercises to optimize the preservation of exercise intensity (large before small muscle group exercises, multiple-joint exercises before single-joint exercises, and higher-intensity before lower-intensity exercises) [7]. These exercises should be applied in adapted contexts and should be contingent upon an individual’s target goals, physical capacity, and training status. 2. Biomechanical Analytics of Resistance Training Exercises Highlight by Micah Gross and Silvio Lorenzetti Recently, technologies such as motion capture, force plates, electromyography (EMG), and computer modelling have been used to assess the impact of resistance training on the human body, and to identify differences between exercises and workout configurations. Typically, effects on the kinematic and kinetic characteristics of movements—or on muscle activation patterns—stand in focus, because a good understanding of these facilitates structuring workouts so as to elicit a desired stimulus and achieve particular goals. With velocity-based training methods gaining popularity in recent years, movement velocity has arguably received the most attention among the kinematic variables of strength training exercises. For example, Weakley et al. [8] assessed the effects of three superset configurations on the kinetics and kinematics of the barbell bench press. These authors advised the use of agonist-antagonist supersets, because this configuration allows subjects to best maintain bar velocity and power across the course of the workout. For similar reasons, Wetmore et al. [9] deemed cluster sets of heavy back squats superior to traditional set configurations; they showed in their study that peak velocity and power, as well as the early attainment of these, was better maintained throughout the workout using cluster sets. Further, Morales-Artacho et al. [10] reported similar advantages of set clustering for ballistic squat jumps. Of interest to novice lifters or in rehabilitation situations, kinetic variables such as forces and torques acting on certain joints, as well the interplay of co-activated muscles, have been investigated, so as to determine the safest ways to achieve adequate strength training stimuli. Comparing unilateral and bilateral squats with the same external load per leg, Eliassen et al. [11] found greater muscle force and higher barbell velocity in the unilateral squats, and therefore recommended these for subjects with low back pain and after ACL ruptures. Elsewhere, Mausehund et al. [12] differentiated three similar unilateral lower-limb squat variants in terms of external load and muscle activation, and accordingly recommended single leg squats for alleviating spinal loading, and split squats with the rear foot elevated for ACL patients, because the greater hamstring co-activation in this exercise helps to stabilize the knee joint. Additionally, studies have investigated the effects of assisting devices while performing strength exercises. Using musculo-skeletal modelling techniques, Sinclair et al. [13] analyzed the acute effects of knee wraps on the kinetics, kinematics, and muscle forces during back squats. The knee wraps reduced muscle forces at a given load, and were suspected to therefore diminish the muscle development stimulus. Elsewhere, the proposed benefits of heel wedges while performing barbell back squats have been investigated. Having used motion capture and EMG to assess trunk and pelvis biomechanics, the studies of both Lee et al. [14] and Charlton et al. [15], performed on recreational and resistance-trained subjects, respectively, agree that heel wedges do not facilitate a neutral spine and are therefore unlikely to prevent back injuries while squatting. 3. Velocity-Based Monitoring of Resistance Training Highlight by Jan Seiler, Fabian Lüthy, and Micah Gross In many sports, developing high muscular power is considered one of the most important performance-determining factors. Power at a given resistance is highly dependent on movement velocity [16], which is an indirect indicator of muscle contraction velocity, and thus of the intensity of a muscle contraction. Hence, measurements of velocity during training have been deemed a practical means of monitoring loading intensity [17], in addition to external load and volume. In recent years, the application of this principle, which has been coined velocity-based training (VBT), has received increasing attention from researchers. Moreover, the popularity of VBT has increased considerably among practitioners, thanks in large part to the introduction of numerous commercial devices for tracking velocity, which include linear position transducers, accelerometers, and video-based smartphone applications [18,19,20]. Two main characteristics of VBT which differ from traditional strength training methods are (1) the use of velocity zones, rather than percentages of 1-RM, for determining resistance, and (2) the use of velocity thresholds, rather than failure or a predetermined number of repetitions, for terminating sets. The first principle intends to prescribe loads based on the individual load-velocity regression and adjust for day-to-day fluctuations in ability [17]. The second principle aims to ensure only high-quality repetitions and to minimize unnecessary fatigue and metabolic stress accumulated in repetitions outside the intended velocity zone [21,22]. Banyard et al. [23] provided evidence for the claimed benefits of VBT over traditional methods. They showed that, over the course of a training session, prescribed movement velocity was better maintained when load was adjusted between sets based on velocity measurements. Moreover, when sets were terminated based on velocity thresholds rather than a predetermined number of reps, subjects completed either fewer sets for the same number of total reps (which was usually more time efficient) or fewer reps in the same number of sets. The generally higher movement velocities with VBT, and—especially—the case where fewer reps per set were completed, corresponded to overall reduced time under tension, which the authors also purported as a benefit of VBT, since mechanical stress is kept to a minimum. Having applied similar VBT principles over a short training phase, the study of Dorrell et al. [24] provides further support for the use of velocity zones rather than traditional percentages of 1-RM for dictating loads. These authors reported similar or greater training adaptations with reduced training volume for VBT. They concluded that monitoring velocity might better assure that day-to-day training corresponds to the prescribed intensity, while also indicating and compensating for subjects’ current state of fatigue [24]. Terminating sets based on a velocity threshold rather than training to or near to failure is arguably the largest difference between VBT and traditional methods. However, an increasing number of investigations appear to indicate that training to muscular failure may not be necessary to produce increments in muscle strength and that the continuous use of that strategy results in a significant decrement in the rate of force development [25,26]. Furthermore, higher thresholds, which terminate sets even earlier, could be preferable to more lenient thresholds. Indeed, Rodriguez-Rosell et al. showed that when reductions in velocity of only 10% were tolerated before terminating sets, similar or greater changes in strength, muscle endurance, jump performance, and sprint performance occurred with less than half as many repetitions, compared with using 30% velocity loss per set [27]. On a larger scale than individual sessions, fatigue monitoring through the use of movement velocity could help to optimize the periodization and planning of subsequent strength training sessions. In this context, Vernon et al. highlighted that movement velocity at loads ≥ 60% 1-RM may be compromised to a stronger degree than either 1-RM itself or countermovement jump performance in the 24–72 h following a strength session [28]. An additional, psychological advantage of device-assisted VBT is the immediate biofeedback. Nagata et al. [29] showed that a four-week training intervention with immediate numerical velocity feedback increased jump squat performance more compared to training with video-feedback or no feedback. The increased performance was also better sustained 10 days post-intervention [29]. Interestingly, Hirsch et al. showed that oral instructions to lift the bar as fast as possible were not as effective as a numerical velocity target for attaining a high movement velocity in male powerlifters [30]. Despite the apparent benefits of VBT with immediate feedback, the financial investment for a feedback device remains a barrier for some strength and conditioning professionals or athletes. In such cases, it is advisable to err on the side of smaller percentage losses in velocity, which, as recently mentioned by Jukic et al. [31], is well facilitated by employing cluster sets in the absence of any measuring device. So far, research on VBT has either standardized or disregarded the influence of preceding eccentric movements on concentric velocity. In practical settings, however, stretch-shortening cycles of the muscle-tendon unit affect concentric movements strongly. Furthermore, different eccentric speeds can induce different adaptive responses following resistance training [32,33]. Eccentric training and eccentric rates of force development sparked the interest of certain researchers recently [34]. Thus, future research should address the role of eccentric actions on training quality, fatigue, and training effectiveness within the context of VBT. 4. Resistance Training for Adults with Musculoskeletal Deficits Highlight by Federico Roggio and Giuseppe Musumeci Injuries to the musculoskeletal system (e.g., lower-extremity injuries, osteoarthritis, etc.) can result in a series of deficits that can lead to reduced long-term health-related quality of life such as impaired gait speed, static and dynamic balance, and stair climbing, and an increased fall risk [35,36,37]. An abnormal gait pattern and a reduced biomechanical symmetry can be linked to a weakness of leg muscles [38,39]. Specifically after the age of 50, muscle strength decreases approximately 15% every 10 years; meanwhile, muscle mass decreases approximately 2% every year [40]. During the past decade, many studies have evaluated the effects of applying resistive loads just in a walking task, and the results indicate that muscles and joints increase their activation, while the metabolic cost increases [41,42,43]. There is strong evidence to suggest that resistance training is an effective method of increasing strength in older adults [44,45]. In order to attenuate the effects of sarcopenia, the recommendation is to perform resistance training 2–3 days per week. There does not exist a definitive gold standard prescription for resistance training exercise because most prescriptions focus on applying a resistive load, which may lead to a training session with low results. In order to reach patient-specific needs, Washabaugh E.P. et al. presented a biomechanical simulation to evaluate the effects of different modes of applying a resistance training during walking [46]. Different methods led to different results, such as quadricep activation rather than hamstring activation. They evaluated five different ways to apply a resistive load, and the results show that (1) a weight attached at the ankle primarily increases resistance to the hamstring muscles; (2) an elastic band attached at the ankle primarily increases resistance to the quadriceps muscles; (3) a viscous device attached to the hip and knee provides resistance to the hamstrings over the stance phase, and to the quadriceps during mid and late swing; (4) a weight attached at the pelvis doesn’t provide an effective improvement; and (5) a constant backwards pulling force at the pelvis increases both quadricep and hamstring activation [47,48]. Thus, when resistance training is used, the correct application method must be selected to ensure improvement according to patient-specific needs. 5. The Role of Capillarization on Skeletal Muscle Adaptation to Resistance Training Highlight by Antonio Paoli and Tatiana Moro Resistance training (RT) is the most efficient strategy to promote muscle hypertrophy and strength. Recently, muscle perfusion and capillary density have emerged as crucial predictors of hypertrophic capacity following RT [49,50], both in young and older individuals. Capillaries have the important function of delivering oxygen, nutrients, and hormones in all tissues. Adequate skeletal muscle capillarization can enhance muscle protein synthesis by ensuring the transport of amino acids and growth factors to muscle fibers. In particular, the delivery of systemic signals, such as insulin-like growth factor-1 (IGF-1), hepatocyte growth factor (HGF), interleukin 6 (IL-6), and myostatin, seems to regulate satellite cell (SC) function, supporting muscle repair and/or remodelling/adaptation [51,52]. Nederveen at al. [53] showed that the distance between capillaries and SCs is greater in older adults compared with younger people. They also observed that after a single bout of RT, active SCs move closer to the nearest capillary whilst quiescent SCs remain at a further distance. This finding suggests that local perfusion supports muscle growth also by promoting SC activity, and may help to explain the different anabolic response to RT typical of aging. Timmerman et al. demonstrated that a moderate acute increase in physical activity can improve nutritive blood flow and stimulate the anabolic response to nutrient intake [54]. We have recently showed that 12 weeks of progressive RT can increase muscle strength by 16%, lean mass by 2%, and muscle cross-sectional area by 27% in healthy older adults [49,50,51,52,53,54]. However, our results suggest that the hypertrophic response to RT is linked to the basal level of capillarization. It seems indeed that the early adaptive cellular response to RT is to increase the density of the microvascular bed and the surface exchange area, which can promote the diffusion of nutrients to the tissue. Only when muscle fibers have adequate perfusion can the rate of protein synthesis increase and lead to muscle growth [49]. These findings lead to the hypothesis that a muscle capillarization threshold may be necessary to promote the hypertrophic adaptation to RT. 6. What Makes Eccentric More Effective than Concentric and Isometric Muscle Actions? Highlight by Helmi Chaabene There are three categories of muscle action. These are isometric, concentric, and eccentric. While concentric and isometric muscle actions are well investigated, eccentric muscle actions are still understudied in the literature. Unlike the concentric and isometric actions, eccentric actions do not fit well into the well-known cross-bridge theory [55]. The winding filament theory has been proposed [56] as an alternative underlying mechanism of eccentric muscle actions. This has advanced our understanding as to the specific properties of eccentric muscle actions compared with isometric and concentric actions. In the context of the winding theory, it has been suggested that during active lengthening contractions (i.e., eccentric actions), the giant protein titin appears to actively participate in the generation of force by increasing its stiffness when winded up onto actin [57]. Titin is activated by Ca2+ release and winds upon the thin filament by the cross-bridges, which also translate as they rotate the thin filament [58]. There is evidence that fundamental differences exist between eccentric and concentric/isometric muscle actions from metabolic and neural perspectives. In terms of metabolic demands, it has been demonstrated that eccentric muscle actions are less taxing and require less energy per unit of work [59,60]. For neural drive, eccentric and concentric muscle actions display considerable differences [61]. Lower electromyography activity during eccentric compared with concentric muscle actions has been reported [62]. This difference seems to be mainly due to a lower number of active motor units in addition to lower discharge rates during eccentric compared with concentric actions [61,63]. Despite the lower metabolic cost and lower neural drive during eccentric actions, higher force production (20–60%) compared with isometric and concentric actions can be observed [64,65]. This makes eccentric actions distinctly more effective and efficient than concentric/isometric actions. Further eccentric exercises generate a greater hypertrophic response compared with isometric and concentric training [66,67]. This is substantiated by the higher anabolic signalling as reflected by a greater satellite cell activation following eccentric compared with concentric muscle actions [68]. Additionally, eccentric exercises result in greater force compared with isometric and concentric training [66]. Moreover, eccentric exercises have the potential to improve muscle power [69,70]. Overall, there is evidence to favor eccentric training over concentric/isometric training to improve muscle mass, strength, and power. Funding This research received no external funding. Conflicts of Interest The authors declare no conflict of interest. ==== Refs References 1. Lopes J.S.S. Machado A.F. Micheletti J.K. de Almeida A.C. Cavina A.P. Pastre C.M. Effects of training with elastic resistance versus conventional resistance on muscular strength: A systematic review and meta-analysis SAGE Open Med. 2019 7 10.1177/2050312119831116 30815258 2. Schoenfeld B.J. Ogborn D. Krieger J.W. Effects of Resistance Training Frequency on Measures of Muscle Hypertrophy: A Systematic Review and Meta-Analysis Sports Med. 2016 46 1689 1697 10.1007/s40279-016-0543-8 27102172 3. Chaves T.S. Pires de Campos Biazon T.M. Marcelino Eder Dos Santos L. Libardi C.A. Effects of resistance training with controlled versus self-selected repetition duration on muscle mass and strength in untrained men PeerJ 2020 8 e8697 10.7717/peerj.8697 32185108 4. Musumeci G. The Use of Vibration as Physical Exercise and Therapy J. Funct. Morphol. Kinesiol. 2017 2 17 10.3390/jfmk2020017 5. Fisher J.P. Ravalli S. Carlson L. Bridgeman L.A. Roggio F. Scuderi S. Maniaci M. Cortis C. Fusco A. Musumeci G. The “Journal of Functional Morphology and Kinesiology” Journal Club Series: Utility and Advantages of the Eccentric Training through the Isoinertial System J. Funct. Morphol. Kinesiol. 2020 5 6 10.3390/jfmk5010006 6. Musumeci G. Sarcopenia and Exercise “The State of the Art” J. Funct. Morphol. Kinesiol. 2017 2 40 10.3390/jfmk2040040 7. American College of Sports Medicine American College of Sports Medicine position stand. Progression models in resistance training for healthy adults Med. Sci. Sports Exerc. 2009 41 687 708 10.1249/MSS.0b013e3181915670 19204579 8. Weakley J.J.S. Till K. Read D.B. Phibbs P.J. Roe G. Darrall-Jones J. Jones B.L. The Effects of Superset Configuration on Kinetic, Kinematic, and Perceived Exertion in the Barbell Bench Press J. Strength Cond. Res. 2020 34 65 72 10.1519/JSC.0000000000002179 28796130 9. Wetmore A.B. Wagle J.P. Sams M.L. Taber C.B. DeWeese B.H. Sato K. Stone M.H. Cluster Set Loading in the Back Squat: Kinetic and Kinematic Implications J. Strength Cond. Res. 2019 33 Suppl. S1 S19 S25 10.1519/JSC.0000000000002972 30694961 10. Morales-Artacho A.J. Garcia-Ramos A. Perez-Castilla A. Padial P. Gomez A.M. Peinado A.M. Perez-Cordoba J.L. Feriche B. Muscle Activation During Power-Oriented Resistance Training: Continuous Vs. Cluster Set Configurations J. Strength Cond. Res. 2019 33 Suppl. S1 S95 S102 10.1519/JSC.0000000000002811 30234695 11. Eliassen W. Saeterbakken A.H. van den Tillaar R. Comparison of Bilateral and Unilateral Squat Exercises on Barbell Kinematics and Muscle Activation Int. J. Sports Phys. Ther. 2018 13 871 881 10.26603/ijspt20180871 30276019 12. Mausehund L. Skard A.E. Krosshaug T. Muscle Activation in Unilateral Barbell Exercises: Implications for Strength Training and Rehabilitation J. Strength Cond. Res. 2019 33 Suppl. S1 S85 S94 10.1519/JSC.0000000000002617 29870422 13. Sinclair J. Mann J. Weston G. Poulsen N. Edmundsen C.J. Bentley I. Stone M. Acute Effects Of knee Wraps/Sleeve On kinetics, Kinematics And muscle Forces During the barbell Back Squat Sport Sci. Health 2019 10.1007/s11332-019-00595-5 14. Lee S.P. Gillis C.B. Ibarra J.J. Oldroyd D.F. Zane R.S. Heel-Raised Foot Posture Does Not Affect Trunk and Lower Extremity Biomechanics During a Barbell Back Squat in Recreational Weight Lifters J. Strength Cond. Res. 2019 33 606 614 10.1519/JSC.0000000000001938 30789547 15. Charlton J.M. Hammond C.A. Cochrane C.K. Hatfield G.L. Hunt M.A. The Effects of a Heel Wedge on Hip, Pelvis and Trunk Biomechanics During Squatting in Resistance Trained Individuals J. Strength Cond. Res. 2017 31 1678 1687 10.1519/JSC.0000000000001655 28538320 16. Oliver J.M. Kreutzer A. Jenke S.C. Phillips M.D. Mitchell J.B. Jones M.T. Velocity Drives Greater Power Observed During Back Squat Using Cluster Sets J. Strength Cond. Res. 2016 30 235 243 10.1519/JSC.0000000000001023 26121432 17. Gonzalez-Badillo J.J. Sanchez-Medina L. Movement Velocity as a Measure of Loading Intensity in Resistance Training Int. J. Sports Med. 2010 31 347 352 10.1055/s-0030-1248333 20180176 18. Courel-Ibanez J. Martinez-Cava A. Moran-Navarro R. Escribano-Penas P. Chavarren-Cabrero J. Gonzalez-Badillo J.J. Pallares J.G. Reproducibility and Repeatability of Five Different Technologies for Bar Velocity Measurement in Resistance Training Ann. Biomed. Eng. 2019 47 1523 1538 10.1007/s10439-019-02265-6 30980292 19. Orange S.T. Metcalfe J.W. Marshall P. Vince R.V. Madden L.A. Liefeith A. Test-Retest Reliability of a Commercial Linear Position Transducer (Gymaware Powertool) to Measure Velocity and Power in the Back Squat and Bench Press J. Strength Cond. Res. 2020 34 728 737 10.1519/JSC.0000000000002715 29952868 20. Perez-Castilla A. Piepoli A. Delgado-Garcia G. Garrido-Blanca G. Garcia-Ramos A. Reliability and Concurrent Validity of Seven Commercially Available Devices for the Assessment of Movement Velocity at Different Intensities During the Bench Press J. Strength Cond. Res. 2019 33 1258 1265 10.1519/JSC.0000000000003118 31034462 21. Izquierdo M. Gonzalez-Badillo J.J. Hakkinen K. Ibanez J. Kraemer W.J. Altadill A. Eslava J. Gorostiaga E.M. Effect of Loading on Unintentional Lifting Velocity Declines During Single Sets of Repetitions to Failure During Upper and Lower Extremity Muscle Actions Int. J. Sports Med. 2006 27 8 24 10.1055/s-2005-872825 16944400 22. Sanchez-Medina L. Gonzalez-Badillo J.J. Velocity Loss as an Indicator of Neuromuscular Fatigue During Resistance Training Med. Sci. Sports Exerc. 2011 43 1725 1734 10.1249/MSS.0b013e318213f880 21311352 23. Banyard H.G. Tufano J.J. Delgado J. Thompson S.W. Nosaka K. Comparison of the Effects of Velocity-Based Training Methods and Traditional 1rm-Percent-Based Training Prescription on Acute Kinetic and Kinematic Variables Int. J. Sports Physiol. Perform. 2019 14 246 255 10.1123/ijspp.2018-0147 30080424 24. Dorrell H.F. Smith M.F. Gee T.I. Comparison of Velocity-Based and Traditional Percentage-Based Loading Methods on Maximal Strength and Power Adaptations J. Strength Cond. Res. 2020 34 46 53 10.1519/JSC.0000000000003089 30946276 25. Pareja-Blanco F. Rodriguez-Rosell D. Sanchez-Medina L. Ribas-Serna J. Lopez-Lopez C. Mora-Custodio R. Yanez-Garcia J.M. Gonzalez-Badillo J.J. Acute and Delayed Response to Resistance Exercise Leading or Not Leading to Muscle Failure Clin. Physiol. Funct. Imaging 2017 37 630 639 10.1111/cpf.12348 26970332 26. Pareja-Blanco F. Rodriguez-Rosell D. Sanchez-Medina L. Sanchis-Moysi J. Dorado C. Mora-Custodio R. Yanez-Garcia J.M. Morales-Alamo D. Perez-Suarez I. Calbet J.A.L. Effects of Velocity Loss During Resistance Training on Athletic Performance, Strength Gains and Muscle Adaptations Scand. J. Med. Sci. Sports 2017 27 724 735 10.1111/sms.12678 27038416 27. Rodriguez-Rosell D. Yanez-Garcia J.M. Mora-Custodio R. Pareja-Blanco F. Ravelo-Garcia A.G. Ribas-Serna J. Gonzalez-Badillo J.J. Velocity-Based Resistance Training: Impact of Velocity Loss in the Set on Neuromuscular Performance and Hormonal Response Appl. Physiol. Nutr. Metab. 2020 in press 10.1139/apnm-2019-0829 28. Vernon A. Joyce C. Banyard H.G. Readiness to Train: Return to Baseline Strength and Velocity Following Strength or Power Training Int. J. Sports Sci. Coach. 2020 in press 10.1177/1747954119900120 29. Nagata A. Doma K. Yamashita D. Hasegawa H. Mori S. The Effect of Augmented Feedback Type and Frequency on Velocity-Based Training-Induced Adaptation and Retention J. Strength Cond. Res. 2018 in press 10.1519/JSC.0000000000002514 30. Hirsch S.M. Frost D.M. Considerations for Velocity-Based Training: The Instruction to Move “as Fast as Possible” Is Less Effective Than a Target Velocity J. Strength Cond. Res. 2019 in press 10.1519/JSC.0000000000003233 31. Jukic I. Tufano J.J. Rest Redistribution Functions as a Free and Ad-Hoc Equivalent to Commonly Used Velocity-Based Training Thresholds During Clean Pulls at Different Loads J. Hum. Kinet. 2019 68 5 16 10.2478/hukin-2019-0052 31531129 32. Stasinski A.-N. Zaras N. Methenitis S. Bogdanis G. Terzis G. Rate of Force Development and Muscle Architecture after Fast and Slow Velocity Eccentric Training Sports 2019 7 41 10.3390/sports7020041 30769873 33. Wilk M. Golas A. Krzysztofik M. Nawrocka M. Zajac A. The Effects of Eccentric Cadence on Power and Velocity of the Bar During the Concentric Phase of the Bench Press Movement J. Sports Sci. Med. 2019 18 191 197 31191087 34. Suchomel T. Wagle J.P. Douglas J. Taber C. Harden M. Haff G.G. Stone M.H. Implementing Eccentric Resistance Training—Part 1: A Brief Review of Existing Methods J. Funct. Morphol. Kinesiol. 2019 4 38 10.3390/jfmk4020038 35. Naili J.E. Wretenberg P. Lindgren V. Iversen M.D. Hedström M. Broström E.W. Improved knee biomechanics among patients reporting a good outcome in knee-related quality of life one year after total knee arthroplasty BMC Musculoskelet. Disord. 2017 18 122 10.1186/s12891-017-1479-3 28327133 36. Pietrosimone B. Blackburn J.T. Padua D.A. Pfeiffer S.J. Davis H.C. Luc-Harkey B.A. Harkey M.S. Stanley Pietrosimone L. Frank B.S. Creighton R.A. Walking gait asymmetries 6 months following anterior cruciate ligament reconstruction predict 12-month patient-reported outcomes J. Orthop. Res. 2018 36 2932 2940 10.1002/jor.24056 29781550 37. Papa E.V. Dong X. Hassan M. Resistance training for activity limitations in older adults with skeletal muscle function deficits: A systematic review Clin. Interv. Aging. 2017 12 955 961 10.2147/CIA.S104674 28670114 38. Blackburn J.T. Pietrosimone B. Harkey M.S. Luc B.A. Pamukoff D.N. Quadriceps function and gait kinetics after anterior cruciate ligament reconstruction Med. Sci. Sports Exerc. 2016 48 1664 1670 10.1249/MSS.0000000000000963 27128669 39. Lewek M. Rudolph K. Axe M. Snyder-Mackler L. The effect of insufficient quadriceps strength on gait after anterior cruciate ligament reconstruction Clin. Biomech. 2002 17 56 63 10.1016/S0268-0033(01)00097-3 40. Quittan M. Aspects of physical medicine and rehabilitation in the treatment of deconditioned patients in the acute care setting: The role of skeletal muscle Wien Med. Wochenschr. 2016 166 28 38 10.1007/s10354-015-0418-x 26758982 41. Washabaugh E.P. Krishnan C. A wearable resistive robot facilitates locomotor adaptations during gait Restor. Neurol. Neurosci. 2018 36 215 223 10.3233/RNN-170782 29526856 42. Washabaugh E.P. Claflin E.S. Gillespie R.B. Krishnan C. A novel application of eddy current braking for functional strength training during gait Ann. Biomed. Eng. 2016 44 2760 2773 10.1007/s10439-016-1553-2 26817456 43. Ravalli S. Castrogiovanni P. Musumeci G. Exercise as medicine to be prescribed in osteoarthritis World J. Orthop. 2019 10 262 267 10.5312/wjo.v10.i7.262 31363456 44. Browning R.C. Modica J.R. Kram R. Goswami A. The effects of adding mass to the legs on the energetics and biomechanics of walking Med. Sci. Sports Exerc. 2007 39 515 525 10.1249/mss.0b013e31802b3562 17473778 45. Reeves N.D. Narici M.V. Maganaris C.N. Effect of resistance training on skeletal muscle-specific force in elderly humans J. Appl. Physiol. 2004 96 885 892 10.1152/japplphysiol.00688.2003 14578365 46. Washabaugh E.P. Augenstein T.E. Krishnan C. Functional resistance training during walking: Mode of application differentially affects gait biomechanics and muscle activation patterns Gait Posture 2020 75 129 136 10.1016/j.gaitpost.2019.10.024 31678694 47. Mun K.R. Yeo B.B.S. Guo Z. Chung S.C. Yu H. Resistance training using a novel robotic walker for over-ground gait rehabilitation: A preliminary study on healthy subjects Med. Biol. Eng. Comput. 2017 55 1873 1881 10.1007/s11517-017-1634-x 28321683 48. Lawrence M. Hartigan E. Tu C. Lower limb moments differ when towing a weighted sled with different attachment points Sports Biomech. 2013 12 186 194 10.1080/14763141.2012.726639 23898690 49. Moro T. Brightwell C.R. Phalen D.E. McKenna C.F. Lane S.J. Porter C. Volpi E. Rasmussen B.B. Fry C.S. Low skeletal muscle capillarization limits muscle adaptation to resistance exercise training in older adults Exp. Gerontol. 2019 127 110723 10.1016/j.exger.2019.110723 31518665 50. Snijders T. Nederveen J.P. Joanisse S. Leenders M. Verdijk L.B. van Loon L.J. Parise G. Muscle fibre capillarization is a critical factor in muscle fibre hypertrophy during resistance exercise training in older men J. Cachexia Sarcopenia Muscle 2017 8 267 276 10.1002/jcsm.12137 27897408 51. Snijders T. Nederveen J.P. McKay B.R. Joanisse S. Verdijk L.B. van Loon L.J. Parise G. Satellite cells in human skeletal muscle plasticity Front. Physiol. 2015 6 283 10.3389/fphys.2015.00283 26557092 52. Nederveen J.P. Joanisse S. Snijders T. Ivankovic V. Baker S.K. Phillips S.M. Parise G. Skeletal muscle satellite cells are located at a closer proximity to capillaries in healthy young compared with older men J. Cachexia Sarcopenia Muscle 2016 7 547 554 10.1002/jcsm.12105 27239425 53. Timmerman K.L. Dhanani S. Glynn E.L. Fry C.S. Drummond M.J. Jennings K. Rasmussen B.B. Volpi E. A moderate acute increase in physical activity enhances nutritive flow and the muscle protein anabolic response to mixed nutrient intake in older adults Am. J. Clin. Nutr. 2012 95 1403 1412 10.3945/ajcn.111.020800 22572647 54. Moro T. Brightwell C.R. Deer R.R. Graber T.G. Galvan E. Fry C.S. Volpi E. Rasmussen B.B. Muscle protein anabolic resistance to essential amino acids does not occur in healthy older adults before or after resistance exercise training J. Nutr. 2018 148 900 909 10.1093/jn/nxy064 29796648 55. Herzog W. Mechanisms of enhanced force production in lengthening (eccentric) muscle contractions J. Appl. Physiol. 2014 116 1407 1417 10.1152/japplphysiol.00069.2013 23429875 56. Nishikawa K.C. Monroy J.A. Uyeno T.E. Yeo S.H. Pai D.K. Lindstedt S.L. Is titin a ‘winding filament’? A new twist on muscle contraction Proc. R. Soc. B Biol. Sci. 2012 279 981 990 10.1098/rspb.2011.1304 57. Hessel A.L. Lindstedt S.L. Nishikawa K.C. Physiological mechanisms of eccentric contraction and its applications: A role for the giant titin protein Front. Physiol. 2017 8 70 10.3389/fphys.2017.00070 28232805 58. Monroy J.A. Powers K.L. Gilmore L.A. Uyeno T.A. Lindstedt S.L. Nishikawa K.C. What is the role of titin in active muscle? Exerc. Sport Sci. Rev. 2012 40 73 78 10.1097/JES.0b013e31824580c6 22157359 59. Penailillo L. Blazevich A. Numazawa H. Nosaka K. Metabolic and muscle damage profiles of concentric versus repeated eccentric cycling Med. Sci. Sports Exerc. 2013 45 1773 1781 10.1249/MSS.0b013e31828f8a73 23475167 60. Hoppeler H. Moderate load eccentric exercise; a distinct novel training modality Front. Physiol. 2016 7 483 10.3389/fphys.2016.00483 27899894 61. Duchateau J. Enoka R.M. Neural control of lengthening contractions J. Exp. Biol. 2016 219 197 204 10.1242/jeb.123158 26792331 62. Bigland-Ritchie B. Woods J.J. Integrated electromyogram and oxygen uptake during positive and negative work J. Physiol. 1976 260 267 277 10.1113/jphysiol.1976.sp011515 978517 63. Pasquet B. Carpentier A. Duchateau J. Hainaut K. Muscle fatigue during concentric and eccentric contractions Muscle Nerve 2000 23 1727 1735 10.1002/1097-4598(200011)23:11<1727::AID-MUS9>3.0.CO;2-Y 11054752 64. Hortobágyi T. Katch F.I. Eccentric and concentric torque-velocity relationships during arm flexion and extension Eur. J. Appl. Physiol. Occup. Physiol. 1990 60 395 401 10.1007/BF00713506 2369913 65. Hollander D.B. Kraemer R.R. Kilpatrick M.W. Ramadan Z.G. Reeves G.V. Francois M. Hebert E.P. Tryniecki J.L. Maximal eccentric and concentric strength discrepancies between young men and women for dynamic resistance exercise J. Strength Cond. Res. 2007 21 34 10.1519/00124278-200702000-00007 17313264 66. Roig M. O’brien K. Kirk G. Murray R. Mckinnon P. Shadgan B. Reid W. The effects of eccentric versus concentric resistance training on muscle strength and mass in healthy adults: A systematic review with meta-analysis Br. J. Sports Med. 2009 43 556 568 10.1136/bjsm.2008.051417 18981046 67. Douglas J. Pearson S. Ross A. Mcguigan M. Chronic adaptations to eccentric training: A systematic review Sports Med. 2017 47 917 941 10.1007/s40279-016-0628-4 27647157 68. Hyldahl R.D. Olson T. Welling T. Groscost L. Parcell A.C. Satellite cell activity is differentially affected by contraction mode in human muscle following a work-matched bout of exercise Front. Physiol. 2014 5 485 10.3389/fphys.2014.00485 25566087 69. Vogt M. Hoppeler H.H. Eccentric exercise: Mechanisms and effects when used as training regime or training adjunct J. Appl. Physiol. 2014 116 1446 1454 10.1152/japplphysiol.00146.2013 24505103 70. Maffiuletti N.A. Aagaard P. Blazevich A.J. Folland J. Tillin N. Duchateau J. Rate of force development: Physiological and methodological considerations Eur. J. Appl. Physiol. 2016 116 1091 1116 10.1007/s00421-016-3346-6 26941023