Table of ContentsView AllTable of ContentsDefinitionTriggersOptimal Reps
Table of ContentsView All
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Table of Contents
Definition
Triggers
Optimal Reps
Hypertrophyis the increase in muscle size. It happens when you challenge your muscles with strength training or weightlifting. This causes small muscle damage, which leads to growth during recovery. Hypertrophy refers to existing muscle fibers getting larger, while muscle growth can also involve creating new muscle fibers in addition to size increases.
To increase hypertrophy, doresistance exerciseslike lifting weights. Eating enoughproteinhelps muscles recover and grow. You also need to get enough rest to allow your muscles to repair. Over time, this process makes your muscles bigger and stronger.
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What Does ‘Hypertrophy’ Mean?
Hypertrophy means an increase in the size of muscle fibers, which happens when muscles grow larger through exercise, especially resistance training like lifting weights. It doesn’t create new muscle fibers but makes the existing ones bigger.
There are three main types of hypertrophy:
People often think of hypertrophy in terms of athletic performance. However, there are other ways hypertrophy can improve one’s overall health outside of sports, including:
Can Hypertrophy Be a Bad Thing?Hypertrophy is generally a good thing, as it means the muscles are growing and getting stronger from exercise. However, it can be harmful when it occurs from overtraining, steroid use, or in the heart due to certain diseases. In these cases, hypertrophy can cause organ dysfunction, injuries, or long-term damage.
Can Hypertrophy Be a Bad Thing?
Hypertrophy is generally a good thing, as it means the muscles are growing and getting stronger from exercise. However, it can be harmful when it occurs from overtraining, steroid use, or in the heart due to certain diseases. In these cases, hypertrophy can cause organ dysfunction, injuries, or long-term damage.
What Triggers Hypertrophy?
To trigger hypertrophy, you need a combination of:
Strength training:The most effective way to induce muscle hypertrophy is through high-intensity strength training. This creates minor damage to muscle fibers, triggering the release of anabolic hormones that promote repair and muscle growth, making the muscles stronger and more resilient to future stress.
Muscle damage:Intense strength training causes microtears in muscles. These microtears trigger muscle repair processes that lead to muscle growth. While soreness isn’t always necessary for hypertrophy, this repair process is essential for building muscle size.
Metabolic stress:Exercises that make your muscles feel a “burn” or “pump,” usually from doing many repetitions, cause metabolic stress. When this happens, your body starts to build muscle, helping your muscles grow even if you’re not using heavy weights.
Hormonal response:Exercise helps your body release important hormones liketestosterone, growth hormone, and IGF-1. These hormones are key for repairing muscles, making them grow, and helping them get stronger.
Proper recovery and nutrition:Muscle growth happens during recovery, not during the workout itself. Rest days between intense sessions allow muscles to repair and grow. A diet rich in protein, carbohydrates, andhealthy fatssupports this process.
Is a 30-Minute Workout Enough to Build Muscle?Thirty-minute workouts two to three times per week can be enough to build muscles, especially if you focus on compound exercises (those that work multiple muscle groups at the same time) and challenge your muscles to fatigue.
Is a 30-Minute Workout Enough to Build Muscle?
Thirty-minute workouts two to three times per week can be enough to build muscles, especially if you focus on compound exercises (those that work multiple muscle groups at the same time) and challenge your muscles to fatigue.
Do You Need to Lift Heavy?
No, you don’t need to lift heavy weights for hypertrophy. Lifting lighter weights can still lead to hypertrophy if you perform enough reps to challenge your muscles and ensure enough rest between sets.The key is to stress your muscles enough to feel a difference without overdoing it.
Muscle hypertrophy is best achieved through a slow, steady process. Large muscle tears from intense workouts may cause rapid growth but increase the risk of injury and overtraining. Smaller, controlled microtears from regular strength training promote safer, more sustainable growth.
Optimizing Reps
The number of reps and rest periods you should do depends on your goals. Generally speaking, to build muscle size, aim for eight to 12 repetitions per set using a weight that is 60% to 80% of your one-rep max (the heaviest weight you can lift for one rep). This range of weight and reps is thought to be most effective for hypertrophy.
How Long Should You Rest Between Reps?Rest intervals of 60 to 120 seconds may be best for building muscle strength and size, research shows. Shorter rest (under 60 seconds) intervals might work for some, but longer rest helps maintain performance and better muscle growth, especially for experienced lifters.
How Long Should You Rest Between Reps?
Rest intervals of 60 to 120 seconds may be best for building muscle strength and size, research shows. Shorter rest (under 60 seconds) intervals might work for some, but longer rest helps maintain performance and better muscle growth, especially for experienced lifters.
Summary
Muscle hypertrophy is the growth of individual muscle cells. This causes your muscles to grow bigger in response to exercise, especially high-intensity weight training. Most of the time, muscle hypertrophy is a good thing; it signals that your muscles are growing normally or responding normally to resistance-training exercises.
Occasionally, hypertrophy can be harmful, especially in diseases of the cardiac muscle tissue. Understanding how muscle hypertrophy works can help you decide on the best way to increase your muscle size and improve your overall muscular performance.
15 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Reggiani C, Schiaffino S.Muscle hypertrophy and muscle strength: dependent or independent variables? A provocative review.Eur J Transl Myol. 2020 Sep;30(3):9311. doi:10.4081/ejtm.2020.9311Jorgenson K, Phillips S, Hornberger T.Identifying the structural adaptations that drive mechanical load-induced growth of skeletal muscle: A scoping review.Cells. 2020 Jul;9(7):1658. doi:10.3390/cells9071658Travis SK, Ishida A, Taber C, Fry A, Stone M.Emphasizing task-specific hypertrophy to enhance sequential strength and power performance.J Funct Morphol Kinesiol. 2020 Dec;5(4):76. doi:10.3390/jfmk5040076Pinckard K, Baskin K, Stanford K.Effects of exercise to improve cardiovascular health.Front Cardiovasc Med. 2019;6(1):69. doi:10.3389/fcvm.2019.00069Green D, Smith K.Effects of exercise on vascular function, structure, and health in humans.Cold Spring Harb Perspect Med. 2018 Apr;8(4):a029819. doi:10.1101/cshperspect.a029819Stozer A, Vodopivc P, Bombek L.Pathophysiology of exercise-induced muscle damage and its structural, functional, metabolic, and clinical consequences.Physiol Res. 2020 Aug;69(4):565–598. doi:10.33549/physiolres.934371Schoenfeld BJ, Fisher JP, Grgic H, et al.Resistance training recommendations to maximize muscle in an athletic population: Position stand of the IUSCA.Int J Strength Conditioning. 2021;1(1). doi:10.47206/ijsc.v1i1.81Krzysztofik M, Wilk M, Wojdala G, Golas A.Maximizing muscle hypertrophy: A systematic review of advanced resistance training techniques and methods.Int J Environ Res Public Health. 2019 Dec;16(24):4897. doi:10.3390/ijerph16244897University Hospitals.How microtears help you to build muscle mass.Lionel University.Metabolic stress in resistance training: What to know.Gharahdaghi N, Phillips B, Szewczyk N, Smith K, Wilkinson D, Atherton P.Links between testosterone, oestrogen, and the growth hormone/insulin-like growth factor axis and resistance exercise muscle adaptations.Front Physiol. 2021 Jan;11(1):621226. doi:10.3389/fphys.2020.621226UC Health.Why rest and recovery are critical for an athlete’s physiological and psychological well-being.Early K, Rockhill M, Bryan A, Tyo B, Buuck D, McGinty J.Effect of blood flow restriction training on muscular performance, pain, and vascular function.Int J Phys Ther. 2020 Dec;15(6):892–900. doi:10.26603/ijspt20200892Iversen V, Norum M, Schoenfeld B, Fimland M.No time to lift? Designing time-efficient programs for strength and hypertrophy: A narrative review.Sports Med. 2021 Jun;51(10):2079–2095. doi:10.1007/s40279-021-01490-1Silva W, Viana R, Santos D, Vancini R, Andrade M, de Lira C.Profiling rest intervals between sets and associated factors in resistance training participants.Sports (Basil). 2018 Dec;6(4):134. doi:10.3390/sports6040134
15 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Reggiani C, Schiaffino S.Muscle hypertrophy and muscle strength: dependent or independent variables? A provocative review.Eur J Transl Myol. 2020 Sep;30(3):9311. doi:10.4081/ejtm.2020.9311Jorgenson K, Phillips S, Hornberger T.Identifying the structural adaptations that drive mechanical load-induced growth of skeletal muscle: A scoping review.Cells. 2020 Jul;9(7):1658. doi:10.3390/cells9071658Travis SK, Ishida A, Taber C, Fry A, Stone M.Emphasizing task-specific hypertrophy to enhance sequential strength and power performance.J Funct Morphol Kinesiol. 2020 Dec;5(4):76. doi:10.3390/jfmk5040076Pinckard K, Baskin K, Stanford K.Effects of exercise to improve cardiovascular health.Front Cardiovasc Med. 2019;6(1):69. doi:10.3389/fcvm.2019.00069Green D, Smith K.Effects of exercise on vascular function, structure, and health in humans.Cold Spring Harb Perspect Med. 2018 Apr;8(4):a029819. doi:10.1101/cshperspect.a029819Stozer A, Vodopivc P, Bombek L.Pathophysiology of exercise-induced muscle damage and its structural, functional, metabolic, and clinical consequences.Physiol Res. 2020 Aug;69(4):565–598. doi:10.33549/physiolres.934371Schoenfeld BJ, Fisher JP, Grgic H, et al.Resistance training recommendations to maximize muscle in an athletic population: Position stand of the IUSCA.Int J Strength Conditioning. 2021;1(1). doi:10.47206/ijsc.v1i1.81Krzysztofik M, Wilk M, Wojdala G, Golas A.Maximizing muscle hypertrophy: A systematic review of advanced resistance training techniques and methods.Int J Environ Res Public Health. 2019 Dec;16(24):4897. doi:10.3390/ijerph16244897University Hospitals.How microtears help you to build muscle mass.Lionel University.Metabolic stress in resistance training: What to know.Gharahdaghi N, Phillips B, Szewczyk N, Smith K, Wilkinson D, Atherton P.Links between testosterone, oestrogen, and the growth hormone/insulin-like growth factor axis and resistance exercise muscle adaptations.Front Physiol. 2021 Jan;11(1):621226. doi:10.3389/fphys.2020.621226UC Health.Why rest and recovery are critical for an athlete’s physiological and psychological well-being.Early K, Rockhill M, Bryan A, Tyo B, Buuck D, McGinty J.Effect of blood flow restriction training on muscular performance, pain, and vascular function.Int J Phys Ther. 2020 Dec;15(6):892–900. doi:10.26603/ijspt20200892Iversen V, Norum M, Schoenfeld B, Fimland M.No time to lift? Designing time-efficient programs for strength and hypertrophy: A narrative review.Sports Med. 2021 Jun;51(10):2079–2095. doi:10.1007/s40279-021-01490-1Silva W, Viana R, Santos D, Vancini R, Andrade M, de Lira C.Profiling rest intervals between sets and associated factors in resistance training participants.Sports (Basil). 2018 Dec;6(4):134. doi:10.3390/sports6040134
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Reggiani C, Schiaffino S.Muscle hypertrophy and muscle strength: dependent or independent variables? A provocative review.Eur J Transl Myol. 2020 Sep;30(3):9311. doi:10.4081/ejtm.2020.9311Jorgenson K, Phillips S, Hornberger T.Identifying the structural adaptations that drive mechanical load-induced growth of skeletal muscle: A scoping review.Cells. 2020 Jul;9(7):1658. doi:10.3390/cells9071658Travis SK, Ishida A, Taber C, Fry A, Stone M.Emphasizing task-specific hypertrophy to enhance sequential strength and power performance.J Funct Morphol Kinesiol. 2020 Dec;5(4):76. doi:10.3390/jfmk5040076Pinckard K, Baskin K, Stanford K.Effects of exercise to improve cardiovascular health.Front Cardiovasc Med. 2019;6(1):69. doi:10.3389/fcvm.2019.00069Green D, Smith K.Effects of exercise on vascular function, structure, and health in humans.Cold Spring Harb Perspect Med. 2018 Apr;8(4):a029819. doi:10.1101/cshperspect.a029819Stozer A, Vodopivc P, Bombek L.Pathophysiology of exercise-induced muscle damage and its structural, functional, metabolic, and clinical consequences.Physiol Res. 2020 Aug;69(4):565–598. doi:10.33549/physiolres.934371Schoenfeld BJ, Fisher JP, Grgic H, et al.Resistance training recommendations to maximize muscle in an athletic population: Position stand of the IUSCA.Int J Strength Conditioning. 2021;1(1). doi:10.47206/ijsc.v1i1.81Krzysztofik M, Wilk M, Wojdala G, Golas A.Maximizing muscle hypertrophy: A systematic review of advanced resistance training techniques and methods.Int J Environ Res Public Health. 2019 Dec;16(24):4897. doi:10.3390/ijerph16244897University Hospitals.How microtears help you to build muscle mass.Lionel University.Metabolic stress in resistance training: What to know.Gharahdaghi N, Phillips B, Szewczyk N, Smith K, Wilkinson D, Atherton P.Links between testosterone, oestrogen, and the growth hormone/insulin-like growth factor axis and resistance exercise muscle adaptations.Front Physiol. 2021 Jan;11(1):621226. doi:10.3389/fphys.2020.621226UC Health.Why rest and recovery are critical for an athlete’s physiological and psychological well-being.Early K, Rockhill M, Bryan A, Tyo B, Buuck D, McGinty J.Effect of blood flow restriction training on muscular performance, pain, and vascular function.Int J Phys Ther. 2020 Dec;15(6):892–900. doi:10.26603/ijspt20200892Iversen V, Norum M, Schoenfeld B, Fimland M.No time to lift? Designing time-efficient programs for strength and hypertrophy: A narrative review.Sports Med. 2021 Jun;51(10):2079–2095. doi:10.1007/s40279-021-01490-1Silva W, Viana R, Santos D, Vancini R, Andrade M, de Lira C.Profiling rest intervals between sets and associated factors in resistance training participants.Sports (Basil). 2018 Dec;6(4):134. doi:10.3390/sports6040134
Reggiani C, Schiaffino S.Muscle hypertrophy and muscle strength: dependent or independent variables? A provocative review.Eur J Transl Myol. 2020 Sep;30(3):9311. doi:10.4081/ejtm.2020.9311
Jorgenson K, Phillips S, Hornberger T.Identifying the structural adaptations that drive mechanical load-induced growth of skeletal muscle: A scoping review.Cells. 2020 Jul;9(7):1658. doi:10.3390/cells9071658
Travis SK, Ishida A, Taber C, Fry A, Stone M.Emphasizing task-specific hypertrophy to enhance sequential strength and power performance.J Funct Morphol Kinesiol. 2020 Dec;5(4):76. doi:10.3390/jfmk5040076
Pinckard K, Baskin K, Stanford K.Effects of exercise to improve cardiovascular health.Front Cardiovasc Med. 2019;6(1):69. doi:10.3389/fcvm.2019.00069
Green D, Smith K.Effects of exercise on vascular function, structure, and health in humans.Cold Spring Harb Perspect Med. 2018 Apr;8(4):a029819. doi:10.1101/cshperspect.a029819
Stozer A, Vodopivc P, Bombek L.Pathophysiology of exercise-induced muscle damage and its structural, functional, metabolic, and clinical consequences.Physiol Res. 2020 Aug;69(4):565–598. doi:10.33549/physiolres.934371
Schoenfeld BJ, Fisher JP, Grgic H, et al.Resistance training recommendations to maximize muscle in an athletic population: Position stand of the IUSCA.Int J Strength Conditioning. 2021;1(1). doi:10.47206/ijsc.v1i1.81
Krzysztofik M, Wilk M, Wojdala G, Golas A.Maximizing muscle hypertrophy: A systematic review of advanced resistance training techniques and methods.Int J Environ Res Public Health. 2019 Dec;16(24):4897. doi:10.3390/ijerph16244897
University Hospitals.How microtears help you to build muscle mass.
Lionel University.Metabolic stress in resistance training: What to know.
Gharahdaghi N, Phillips B, Szewczyk N, Smith K, Wilkinson D, Atherton P.Links between testosterone, oestrogen, and the growth hormone/insulin-like growth factor axis and resistance exercise muscle adaptations.Front Physiol. 2021 Jan;11(1):621226. doi:10.3389/fphys.2020.621226
UC Health.Why rest and recovery are critical for an athlete’s physiological and psychological well-being.
Early K, Rockhill M, Bryan A, Tyo B, Buuck D, McGinty J.Effect of blood flow restriction training on muscular performance, pain, and vascular function.Int J Phys Ther. 2020 Dec;15(6):892–900. doi:10.26603/ijspt20200892
Iversen V, Norum M, Schoenfeld B, Fimland M.No time to lift? Designing time-efficient programs for strength and hypertrophy: A narrative review.Sports Med. 2021 Jun;51(10):2079–2095. doi:10.1007/s40279-021-01490-1
Silva W, Viana R, Santos D, Vancini R, Andrade M, de Lira C.Profiling rest intervals between sets and associated factors in resistance training participants.Sports (Basil). 2018 Dec;6(4):134. doi:10.3390/sports6040134
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