Fitness Training Benefits Hypertrophy

Defining Muscular Hypertrophy & Growth Training Best Practices

Nicole Golden
Nicole Golden
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Muscle hypertrophy is the process of increasing muscle size, typically through weightlifting and resistance training.

Getting big, toned muscles is one of the most common goals Certified Personal Trainers help their clients achieve. One thing to remember is that muscle size and muscle strength are connected but not necessarily the same thing. You can have big muscles that aren’t incredibly strong and strong muscles that aren’t massive. That also means that hypertrophy training is a different process from strength training.

Here’s what you need to know about training for hypertrophy.

table of contents

Want to know how to design the most effective hypertrophy training programs? Consider becoming an NASM Certified Personal Trainer!

What is Hypertrophy?

Muscle hypertrophy (sometimes referred to as muscle building) is the increase in the size, density, and shape of skeletal muscles that is usually achieved through weightlifting or other types of resistance training.

Hypertrophy is typically a slow process. Most muscle tissue is made up of different kinds of proteins. When you lift heavy loads, the muscles tear and the body experiences metabolic stress. In response to this, the body tells the proteins to increase, and the muscles slowly grow. Then, to keep growing your muscles, you have to keep increasing weightlifting volumes over time.

There are several ways you can train to make your muscles bigger. Most hypertrophy training plans focus on lifting heavier loads for a smaller number of reps and sets. However, different bodies might respond differently to the same programs, so there is usually some trial and error when finding your optimal training plan.

what are the benefits of hypertophy training?

Any resistance training program has significant health benefits (i.e., weight loss, reduced risk of cardiovascular and metabolic diseases, etc.). But if you want next-level results and even more health benefits, you need to train at higher volumes and intensities than most standard home or class workouts.

Here are some of the benefits of hypertrophy training:

  • Reducing the risk of cardiovascular disease. Recent research has shown that middle-aged people with the highest skeletal muscle mass had the lowest risk of having a cardiovascular event (5).
  • Improving metabolic function. Increased muscle mass has been shown to improve insulin sensitivity and glucose control (4).
  • Maintaining mobility. Higher levels of skeletal muscle mass in older adults are directly correlated with the ability to complete daily activities and increased independence (1).
  • Reducing loss of bone density (osteoporosis). Lifting heavy loads requires the bone to adapt as well as the muscles and connective tissue, which leads to stronger bones and a reduction of the risk of osteoporosis (3).

what are the risks of hypertrophy training?

Hypertrophy training can sometimes result in overuse injuries like tendonitis/tendinosis or low-grade muscle tears, especially when the lifter doesn’t properly rest and recover. Lifters who try to lift too much or have poor form can get more serious acute injuries like ruptured discs, ligament tears, fractures, or high-grade muscle tears.

Most of these risks can be avoided if you follow a structured program from a qualified trainer who knows your capabilities. In fact, hypertrophy is a more advanced form of training. In the OPT model, it’s phase 3. Before you start hypertrophy training, you should have good stability, muscle endurance, and optimal movement patterns to prevent injury.

hypertrophy vs. strength training

Hypertrophy training and strength training are two different approaches to fitness training and building muscle.

Hypertrophy training

Hypertrophy training focuses on building big muscles (e.g., bodybuilding). Bodybuilders are judged on the aesthetic appearance of their muscles.

Bodybuilders and people focused on hypertrophy often train at high volumes with lighter loads. The optimal set, rep, and intensity ranges for muscle hypertrophy is 7585% 1 RM for 35 sets of 612 reps. Some people train in the 630 rep range at lower intensities depending on the muscle group and the person’s response to training.

Strength training

Strength training focuses on building strong muscles (e.g., powerlifting). Powerlifters are judged on their maximum force output compared to their body size.

Powerlifters and other strength trainers usually lift lower volumes but with higher intensity (low reps and high loads). The optimal set, rep and intensity ranges for strength training is 85-100% of 1 RM for 15 reps for 46 sets (2).

Similarities between hypertrophy and strength training

There is some overlap between hypertrophy and strength training. When you train for hypertrophy, your muscles do get stronger. And when you train for strength, your muscles may achieve hypertrophy, especially if your strength training plan has higher reps and sets.

How hypertrophy and muscular development work

Although the general principle of progressive overload (increasing volume over time) applies to hypertrophy training, there are different mechanisms by which the muscle adapts to training stress. Let’s look at these more in detail. 

  1. Exercise-Induced Muscle Damage

When muscles lengthen under tension (the eccentric phase of an exercise), the muscle fibers experience small tears. The body repairs those tears, strengthening the existing muscle tissue so it can withstand that same stress again. As slowly increase volume, your muscles continue to tear and repair to become even stronger.

  1. Metabolic Stress

Metabolic stress is the body’s response to the training that leads to the buildup of metabolites (molecules that serve specific functions, like lactic acid, inorganic phosphate, etc.). These metabolites then increase hormones, signaling the body to build more muscle tissue, especially if the muscle is pushed to failure during the lift.

  1. Mechanical Tensions (Force)

Muscle and connective tissue have receptors sense how much tension the muscle is under and how many muscle fibers it needs to activate to complete a movement. The heavier the load, the more muscle fibers are activated at once, maximizing the force that muscle produces to move the load. Then the muscle increases muscle protein synthesis (building new muscle) so it can withstand the same load again.

Check out this NASM-CPT podcast episode for some more information on the biomechanics of hypertrophy.

  1. Fascia Stretch Training

Fascia is a connective tissue that surrounds your muscles and organs, keeping them in place. Some people genetically have thicker fascia than others, which might keep the muscles from being able to get quite as big. Fascia stretch training can help with this problem.

There are several protocols for fascia stretch training, but the general idea is to lift extremely high volumes to push a lot of oxygenated blood into the muscle over a short period of time. These lifts force the fascia tissue to stretch and expand. And the extra oxygenated blood can help the muscle grow and repair. For proper fascia stretch training, try adding extra sets at the end of a workout, lifting to failure.

Learn more about stretching and hypertrophy by listening to our NASM-CPT podcast to get more info.

How to Train for Hypertrophy – Acute Training Variables

Acute training variables are the sets, reps, sets, load, tempo, and rest when completing training. Hypertrophy training has specific guidelines:












7585% 1 RM




060 seconds

*2-0-2 refers to a two-second down movement (eccentric phase), no pause, and a two-second up movement (concentric phase). 


A repetition (rep) is one completed movement. You can change the number of reps to increase or decrease the training volume. For hypertrophy training, you want to create tension and push the muscles to failure. A repetition maximum (RM) is the most weight you can lift for a few reps.

So, how many sets do you need for hypertrophy? For most people, the most efficient way to achieve muscle hypertrophy is the 612 rep range with loads of 7585% 1 RM. You can complete a set number of reps and load for each set, or you can pyramidincreasing the load and dropping off reps as you progress through each set.

You can also work out within these ranges over the course of the week. For example, you could do 34 sets of 10 reps at 75% 1 RM on Mondays and 4 sets of 6 reps at 85% on Wednesday (Clark et al., 2018).


A set is a series of reps. For hypertrophy, you should determine the number of sets by training levelare you a beginner, intermediate, or advanced lifter?

Beginner (Less Than 1 Year of Training)

Intermediate (12 years of training)

Advanced (23 years of training)


3 sets


46 sets


67 sets


We also recommend adding 12 warm-up sets to prime the muscles.


In physics class, you might have learned that force is equal to the mass of an object multiplied by that object’s accelerationhow hard do you have to push or pull something to move it. In resistance training, your muscles generate force to move dumbbells and barbells. Over time, you can add heavier weights that force muscles to grow and produce more force.

Muscle hypertrophy can occur at lower loads for beginners, but advanced lifters need a higher load for muscle growth. The lower the number of reps in a set, the heavier a load a person can generally lift before fatigue sets in (rep maximum or RM). Here’s a helpful chart that illustrates the highest percentage of 1 RM for number of reps:

Number of reps

Percentage of 1 RM

















(National Strength and Conditioning Association, 2024)

Time Under Tension

Time under tension (TUT) is the amount of time the muscle is under strain during an exercise. In hypertrophy training, the cells need to be under tension long enough for the muscle to get biggerusually around 4070 seconds. But you can also start with a shorter amount of time and increase the TUT over time to make your muscles even bigger, just like you would increase the weight or reps or sets.


Cadence is the timing of muscle contractions during a lift. There are three types of muscle contractions:

  • Concentric When the muscle shortens under a load
  • Eccentric When the muscle lengthens under a load
  • Isometric when the muscle contracts but doesn’t change length

For example, in a barbell squat, the eccentric contraction happens when you unrack the bar and descend into a squat. An isometric contraction occurs when you pause at the bottom of the squat. And the concentric contraction drives the bar back up.

The ideal cadence for muscle hypertrophy is 2/0/2. This means the lifter will spend two seconds in the eccentric phase, zero seconds in an isometric hold, and two seconds in the concentric phase of an exercise (Clark et al., 2018).

Rest Intervals

Rest intervals are the period when you rest between sets. For most training, resting for up to a minute will allow your body to recharge about 8590% of your energy (ATP). However, if you’re lifting very heavy loads above 85% of the 1 RM, you’ll probably need 35 minutes to fully restore ATP.

What is progressive overloading?

Progressive overloading is the process of gradually increasing the acute variables (load, reps, or sets) to strengthen your skeletal muscles.

Training creates stress. If you put too much stress on your muscles too quickly, you can get injured. If you don’t put enough stress on your muscles, you can lose muscle mass and strength. But if you increase the stress very slowly, the body adapts to that stress and becomes stronger.

Hypertrophy Nutrition Tips

Nutrition is as important as training when it comes to muscle hypertrophy.

Here is a list of nutrition tips to get the most out of your hypertrophy training:

  • Eat enough complete, high-quality protein. Eat 1.52 g/kg of your body weight in protein per day for optimal hypertrophy. The protein should contain a high amount of the amino acid leucine, which is responsible for muscle protein synthesis. Whey protein is a great option for leucine. Eating less protein may not be enough to rebuild muscles, and eating more doesn’t usually give you more benefits.
  • Space your protein throughout the day. Your body can only use approximately 2040 g of protein per meal. For best results, eat around this much protein every 34 hours.
  • Eat carbohydrates. Your muscles need carbs to fuel and recover from your workouts. At least 40% of your total daily calories should come from good carbs. Eat carbs 6090 minutes prior to your workout, and then eat a combo of carbs and protein (2:1 ratio) within an hour after you finish.
  • Include micronutrients in your diet. Most people are deficient in Vitamin D, which is necessary for muscle building. Pre-menopausal women might also be lacking iron. Consider taking multivitamins if your diet doesn’t contain enough nutrients.
  • Eat enough calories. If you want to build muscle, you need to give it building materials. Use a resting metabolic rate calculator to figure out how many calories you need to eat daily to maintain your weight. You can also eat a bit more than that to really build your muscle.
  • Use supplements to supplement. Make sure you have a healthy diet that meets the above requirements and then use supplements to add anything else you might need. Creatine monohydrate is generally safe and can help you build more muscle mass. Always check with your doctor before starting any supplement.

Sample Hypertrophy Workout Plan

The best hypertrophy workout plans use periodizationa program design with different levels of specificity, intensity, and volume. Periodization training divides your workouts into a macrocycle (large block of training that usually lasts a year) which is made up of several mesocycles (smaller blocks of training that usually last a month each).

There are two types of periodization: linear and undulating. Linear periodization is when you switch between training phases for each mesocycle. Undulating periodization is when you switch between training phases during each mesocycle.

Linear periodization hypertrophy workout plan

Here’s an example of a hypertrophy training plan that uses linear periodization that focuses on lifting progressively heavier loads for hypertrophy, short periods of deloading, and maximum strength training.

Weeks 14

Week 5

Weeks 610

Week 11

Weeks 1215

Week 16



Maximum strength




During linear periodization, focus on adding volume (reps, sets, load) to the workout during hypertrophy phases and adding a load to each maximum strength phase. Each deload should reduce volume by around 50%.

Linear periodization hypertrophy workout plan

Here’s an example of a hypertrophy training plan that uses undulating periodization that alternates between hypertrophy and maximum strength cycles with three workouts per week with one-week breaks for deloading in between.

Weeks 14

Week 5

Weeks 610

Week 11

Weeks 1215

Week 16

Workout 1


Workout 2


Workout 3

Maximum Strength


Workout 1


Workout 2

Maximum Strength

Workout 3

Maximum Strength


Workout 1


Workout 2


Workout 3

Maximum Strength


Become a Personal Trainer

Want to learn more about the science behind building muscle to help yourself and others maximize their gains? Consider becoming a Certified Personal Trainer by enrolling in the NASM Certified Personal Trainer course. Our program is the most well-received personal trainer preparation course. It’s based on the latest research in exercise science and with the most effective methods. Enroll now!

The Author

Nicole Golden

Nicole Golden

Nicole Golden has been a health/fitness professional since 2014 when she left the field of education to pursue a full-time career in fitness. Nicole holds a Master of Science degree from Concordia University Chicago in Applied Exercise Science with a concentration in Sports Nutrition. She is an NASM Master Trainer, CES, FNS, BCS, CSCS (NSCA) and AFAA certified group fitness instructor. Nicole is a sports nutritionist (CISSN) certified through the International Society of Sports Nutrition. She is the owner of FWF Wellness where she specializes in corrective exercise, nutrition coaching, and training special populations. She has a great deal of experience working with a wide variety of clients including female athletes, cancer survivors, older adults with medical comorbidities, and clients who have undergone bariatric surgery. She also has a special interest in coaching clients in recovery from Substance Use Disorders. Nicole enjoys spending time with her husband and five children when she is not training clients or teaching fitness classes. Follow her on LinkedIn!


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