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The Mechanisms of Muscle Hypertrophy and Their Application to Resistance Training

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Abstract

The quest to increase lean body mass is widely pursued by those who lift weights. Research is lacking, however, as to the best approach for maximizing exercise-induced muscle growth. Bodybuilders generally train with moderate loads and fairly short rest intervals that induce high amounts of metabolic stress. Powerlifters, on the other hand, routinely train with high-intensity loads and lengthy rest periods between sets. Although both groups are known to display impressive muscularity, it is not clear which method is superior for hypertrophic gains. It has been shown that many factors mediate the hypertrophic process and that mechanical tension, muscle damage, and metabolic stress all can play a role in exercise-induced muscle growth. Therefore, the purpose of this paper is twofold: (a) to extensively review the literature as to the mechanisms of muscle hypertrophy and their application to exercise training and (b) to draw conclusions from the research as to the optimal protocol for maximizing muscle growth.
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THE MECHANISMS OF MUSCLE HYPERTROPHY AND THEIR APPLICATION TO RESISTANCE TRAININ
Brad J Schoenfeld
Journal of Strength and Conditioning Research; Oct 2010; 24, 10;
ProQuest Health and Medical Complete
pg. 2857
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Reproduced with permission of the copyright owner. Further reproduction prohibited without permission.
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... Aerobic training has demonstrated significant improvements in inflammatory markers and cardiorespiratory fitness, contributing to better cardiovascular health (Ferrari et al., 2020;Pei et al., 2019;Diniz et al., 2021). Resistance training is essential for enhancing muscle strength and functional performance, addressing the prevalent issue of sarcopenia in CKD patients (Corrêa et al., 2021a;Gadelha et al., 2021;Schoenfeld, 2010). Combined training may provide synergistic benefits by targeting both cardiorespiratory and musculoskeletal outcomes (Burrai et al., 2021;Chung et al., 2017). ...
... One of the primary mechanisms driving the benefits of resistance training is the promotion of muscle hypertrophy. Resistance training involves subjecting muscles to external resistance, which leads to muscle damage at the microscopic level (Schoenfeld, 2010;Lim et al., 2022). This damage triggers a repair and growth process, primarily promoted by the activation of satellite cells, leading to muscle regeneration and growth (Fukada et al., 2022). ...
... Moreover, resistance training stimulates the synthesis of muscle proteins, especially myofibrillar proteins (Schoenfeld, 2010;Schiaffino et al., 2013). The mechanistic target of rapamycin ...
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... Consequently, research endeavors have intensified, focusing on strategies to enhance muscle mass, commonly referred to as muscle hypertrophy (Schoenfeld, 2010). ...
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... Schoenfeld suggests that combining hypertrophy and strength training within a periodized program can lead to optimal muscle growth and strength improvements, offering a balanced approach to knee strengthening. 10 Alternating between these repetition schemes can prevent plateaus and maintain continuous progress. ...
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This article provides a comprehensive analysis of knee strengthening post-surgery, focusing on key performance indicators (KPIs) essential for recovery and performance enhancement. The study delves into the importance of range of motion (ROM), load management through repetitions maximum (RM) and velocity-based training (VBT), speed variations, repetition schemes for hypertrophy and strength, and the assessment of pain, inflammation, and effusion. Emphasis is placed on dynamic alignment, muscle activation, and rate of perceived exertion (RPE) to tailor individualized rehabilitation programs. The integration of these KPIs ensures a balanced approach, enhancing muscle strength and joint integrity while minimizing injury risk. Regular monitoring and adjustments based on these indicators are recommended to optimize outcomes and ensure sustained progress in knee function and overall mobility.
... This means that training should be tailored to meet your individual goals. For example, if your primary goal is strength, your workouts should focus on lifting heavy weights with fewer reps (1)(2)(3)(4)(5)(6), while if your goal is hypertrophy (muscle growth), you may focus on moderate weights with higher repetitions (8)(9)(10)(11)(12). ...
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... So in this study measuring lower limb muscle strength, it is assumed that there is no difference between genders (Bartolomei et al., 2021). Subject characteristics between the two groups (age, weight, height, body mass index) were not significantly different, with a mean age of 27 years, indicating that the average participant is still in the productive age range that allows muscle strengthening training with a relatively smaller risk of injury and has good awareness (Schoenfeld, 2010). The mean BMI is in the normoweight category based on Asia Pacific criteria (WHO, 2000). ...
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Introduction: Athletes with CP were more prone to limb injuries. Stretching had long been considered beneficial for improving muscle performance and reducing the risk of injury. Proprioceptive Neuromuscular Facilitation was a technique used to enhance muscle elasticity and increase peak torque and muscle strength. Objective: To analyze the effect of adding Proprioceptive Neuromuscular Facilitation exercises on quadriceps and hamstring muscle strength in cerebral palsy athletes. Methodology: The study was conducted at the NPC Indonesia Training Center. The subjects consisted of 24 athletes diagnosed with cerebral palsy, aged 18-40 years, who underwent intervention three times per week for four weeks on both limbs. The subjects were divided into two groups: 12 individuals in the treatment group received a resistance training program with additional Proprioceptive Neuromuscular Facilitation exercises, and 12 in the control group underwent resistance training only. Results: There was a significant increase in muscle strength in the treatment group for the dominant quadriceps (p=0.043), non-dominant quadriceps (p=0.001), dominant hamstring (p=0.002), and non-dominant hamstring (p=0.008). In the control group, significant increases were observed in the dominant hamstring (p=0.024) and non-dominant hamstring (p=0.013), but not in the dominant quadriceps (p=0.530) or non-dominant quadriceps (p=0.420). Compared to the control group, a significant difference was found in non-dominant quadriceps strength (p=0.020), but no differences were observed in dominant quadriceps strength (p=0.396) or hamstring strength (p=0.271, p=0.204). Conclusions: The addition of Proprioceptive Neuromuscular Facilitation exercises significantly increased quadriceps and hamstring strength in cerebral palsy athletes compared to those without it.
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