How Many Sets And Reps To Build Muscle? The Optimal Amount

The Science Behind Sets: Reps, Hypertrophy, and Everything In Between

Although there are a variety of different strength training goals, such as increasing overall muscular strength or reducing the risk of injury, many people who engage in resistance training are ultimately looking to build muscle.

Muscle building, which is referred to as hypertrophy training, can be accomplished with consistent strength training workouts and a proper diet.

It does not happen overnight, however, so commitment to your training and nutrition program is crucial for significant muscle gains.

But, when it comes to hypertrophy workouts, how many sets and how many reps to build muscle are recommended? 

To ensure optimal muscle growth while minimizing the risk of injury the recommended number of reps to build muscle typically falls within the range of 6-12 reps per exercise.

Keep reading to find out why!

A stack of green, yellow and black weight plates.

How Many Sets And Reps To Build Muscle?

As a quick review, the term reps is short for repetitions.

A rep refers to one complete movement of an exercise.

For example, one rep of a squat begins with standing upright, then bending your hips and knees and, sitting your hips back to squat down, then returning back up to the starting position.

A set in exercise refers to a series of reps (repetitions) of a given exercise that are performed together as a unit back to back without rest in between.

So, what are the recommendations for how many reps to build muscle?

Numerous research studies have concluded that high-volume resistance training is the best method for building muscle.1Schoenfeld, B. J., Ogborn, D., & Krieger, J. W. (2017). Dose-response relationship between weekly resistance training volume and increases in muscle mass: A systematic review and meta-analysis. Journal of Sports Sciences35(11), 1073–1082.

“High volume” involves doing enough reps and sets and lifting enough weight. 

A person holding a kettlebell just off the floor.

So, how many reps should I do to build muscle?

Although different fitness organizations recommend slightly different rep ranges for building muscle and other fitness goals, the optimal number of reps for hypertrophy (hypertrophy) is 6-12 reps per exercise. 2Baz-Valle, E., Balsalobre-Fernández, C., Alix-Fages, C., & Santos-Concejero, J. (2022). A Systematic Review of the Effects of Different Resistance Training Volumes on Muscle Hypertrophy. Journal of Human Kinetics81(1), 199–210.

In terms of the number of sets to build muscle, most fitness experts and personal trainers recommend doing 3 to 6 sets.

Of course, this will depend on the number of reps you are doing, the load you are using, the exercise you are doing, your fitness level, and the number of exercises you are doing in the workout.

Your 1RM, which is your one-repetition maximum, refers to the maximum load you can possibly lift with proper form for one complete rep of an exercise.

The optimal load or weight to use to build muscle is suggested to be 67-85% of your 1RM.

For example, if the maximum weight that you can bench press for one rep is 160 pounds, but you are unable to lift that load for two complete repetitions without “cheating,” then your 1RM for the bench press is 160 pounds.

A man doing an incline leg press.

Your 1RM for an exercise has practical applications besides just serving as a benchmark to periodically assess your fitness progress and improvements in strength.

The strength continuum refers to a framework by which the appropriate load to lift can be determined based on the number of reps that you are performing.

According to the National Strength and Conditioning Association (NSCA)3TRAINING LOAD CHART. (n.d.)., the following table shows the percentage of your 1RM you should use for the given number of reps of an exercise:

Maximum Number of RepsPercent of 1RM Load

This strength continuum correlates quite well with the recommendations for the amount of weight you should lift to build muscle, according to ACE Fitness (67-85% of your 1RM).

If we look at 12 reps, the recommended load is 70% of your 1RM, while if you are only doing six reps, you should use 85% of your 1RM.

So, returning to the example of the athlete who has a 1RM for the bench press of 160 pounds to build muscle, the recommendation is to perform 6 to 12 reps at 67 to 85% of the 1RM.

Using the chart above, 70 to 85% of the 1RM depending on the number of reps you have chosen to do.

Therefore, if you want to go with the low-weight higher reps route within the recommended hypertrophy reps and load range, you would use 70% of your 1RM (160 x 0.7 = 118 pounds) for sets of 12 reps each. 

This would probably be rounded to 120 pounds so that you could easily load up the barbell with available weight plates.

A person doing a bicep curl in the mirror.

If you would prefer to go the high-weight low reps route within the muscle-building recommendations, you could perform 6 reps of the exercise with 85% of your 1RM weight (160 x 0.85 = 136 pounds). 

Again, because weight plates only come in certain weights, this would probably be rounded up to 140 pounds.

Of course, you can also use a different number of reps between the recommended 6-12 rep range for building muscle with the appropriate load based on the 1RM strength continuum and your own personal goals. Find your own sweet spot for strength gains!

Ultimately, variety is best. In other words, for some weight training workouts, use heavier weights (closer to 85% of your 1RM) for fewer reps (5-8 reps), and lift lighter weights (closer to 70% of your 1RM) for more reps (10-12 reps).4Schoenfeld, B., Contreras, B., Ogborn, D., Galpin, A., Krieger, J., & Sonmez, G. (2016). Effects of Varied Versus Constant Loading Zones on Muscular Adaptations in Trained Men. International Journal of Sports Medicine37(06), 442–447.

‌It’s important to note that hypertrophy, or building muscle, isn’t necessarily correlated with increasing strength. 

A person taking dumbbells from a rack.

Although research shows5Schoenfeld, B. J., Contreras, B., Krieger, J., Grgic, J., Delcastillo, K., Belliard, R., & Alto, A. (2018). Resistance Training Volume Enhances Muscle Hypertrophy. Medicine & Science in Sports & Exercise51(1), 1. high-volume resistance training may be best for increasing muscle mass, gains in muscle may not necessarily be accompanied by increases in strength. 

For a training program designed to increase muscular strength, do 1-6 reps with loads that are at least 85% of your 1RM. Usually, athletes looking to increase strength do 3-6 sets per exercise. 

Lastly, in terms of the best exercises you should do to build muscle, the bulk of your training should involve performing compound weightlifting exercises6Gentil, P., Soares, S., & Bottaro, M. (2015). Single vs. Multi-Joint Resistance Exercises: Effects on Muscle Strength and Hypertrophy. Asian Journal of Sports Medicine6(1). like squats, deadlifts, lunges, step-ups, pull ups, bench press, etc.

However, studies suggest that isolation exercises like biceps curls can also help build muscle mass. 

Specific Rep Ranges

On the internet, you will find all sorts of trainers recommending the “best” new workout. Hopefully, we have addressed the optimal number of repetitions above, highlighting that many different options work. But let’s talk specifics.

Will 3 sets of 5 reps build muscle?

Yes, 3 sets of 5 reps can build muscle, especially if the weight lifted is within the appropriate intensity range (around 85% of one’s 1RM). This generally falls into the strength-building range rather than hypertrophy and as such will suits powerlifters, but it will still contribute to muscle growth.

A person doing a barbell back squat with light weight.

Is 12 reps better than 8 reps?

Both rep schemes can contribute to muscle hypertrophy, but 12 reps may target muscle endurance and hypertrophy to a slightly greater extent compared to 8 reps. It depends on the weight used.

Is 4 sets of 12 reps too much?

It depends on individual factors such as fitness goals, but 4 sets of 12 reps can be effective for promoting muscle size and metabolic stress.

Are 4 sets of 8 reps the best for gaining muscle mass?

4 sets of 8 reps with heavy weights can be effective for gaining muscle mass and strength, especially when combined with proper form and progressive overload.

How Many Exercises Per Muscle Group?

Typically, 2–6 exercises per muscle group are recommended for a well-rounded workout plan. Focus on compound exercises for optimal muscle adaptations.

What about 3 sets of 15 reps?

15 reps would be considered high reps. You’d probably need to use light weights or body weight, and of course, it depends on the body part you are training.

It will still be beneficial but will likely be aimed at muscular endurance rather than muscular hypertrophy.7Schoenfeld, B. J., Contreras, B., Krieger, J., Grgic, J., Delcastillo, K., Belliard, R., & Alto, A. (2018). Resistance Training Volume Enhances Muscle Hypertrophy. Medicine & Science in Sports & Exercise51(1), 1.

High reps can sometimes be a good way to practice good form.

A person lifting a kettlebell with one arm.

How To Build Muscle Lifting Weights

Strength training isn’t just for bodybuilders; it has many health benefits, such as increasing muscle mass, increasing bone density, and reducing the risk of chronic disease.

But how many reps and sets do you need to do to build muscle? 

Before we try to establish some recommendations for how many reps you should do to build muscle, it is helpful to briefly review how lifting weights helps build muscle, as this can influence how many reps and sets you need to do to build muscle based on your fitness level.

Muscle building is referred to as hypertrophy.

In order for muscles to grow or increase in size, they need a sufficient stimulus. This stimulus comes by way of your resistance training workouts.

When you lift weights or perform strength training exercises, some amount of structural damage occurs to your muscle fibers.

A person doing a barbell snatch.

This microscopic damage is actually desirable because it is what triggers the body to initiate the muscle proteins synthesis process, which is the process by which muscle fibers are repaired after exercise and resultantly strengthened and enlarged.

In order to induce damage to your muscle fibers, you need to overload your muscles. 

“Overload“ means that you are exceeding the current strength and capacity of your muscles within reasonable limits.

In other words, you do not want to do such easy strength training workouts because your muscle fibers will not experience enough microscopic tearing necessary to stimulate muscle repair and growth. 

On the other end of the spectrum, you can’t blow your muscles out of the water with an extreme number of reps and sets or some crazy amount of weight you cannot possibly lift because you will end up injuring yourself.

Those “microscopic tears“ can become serious and significant tears, which also is not what you need. 

A person lifting a gym sandbag.

Rather, the process of hypertrophy training involves careful and deliberate progressive overload of your muscles in a calculated way that causes just enough overload to trigger muscle growth without inducing injury.

When we discuss overloading the muscles, the “load“ refers to the workload or training volume in a workout.

There are several training variables in a strength training workout that contribute to the workload of your muscles.

The number of reps and sets to build muscle, the weight or load that you use for each exercise, and the number of exercises that you do in the workout all contribute to the training volume and workload in a given hypertrophy training workout.

The dynamic interplay between these various factors will determine the effectiveness of your muscle gains.

Now that we’ve answered your questions, you must choose your exercises!

For a complete list of compound exercises to work into your next strength training sessions, check out our guide: A Complete List of Compound Exercises To Spice Up Your Training.


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Amber Sayer is a Fitness, Nutrition, and Wellness Writer and Editor, as well as a NASM-Certified Nutrition Coach and UESCA-certified running, endurance nutrition, and triathlon coach. She holds two Masters Degrees—one in Exercise Science and one in Prosthetics and Orthotics. As a Certified Personal Trainer and running coach for 12 years, Amber enjoys staying active and helping others do so as well. In her free time, she likes running, cycling, cooking, and tackling any type of puzzle.

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