Illustration of a man doing a Zercher squat.

The Hypertrophy Rep Range: How Many Reps to Build Muscle?

How many reps should you do to gain muscle mass? In strength training, doing five reps per set is a popular way to gain mass. In bodybuilding, though, where the goal is to build bigger muscles as fast as possible, most people do sets of 8–12 reps. Which rep range stimulates more muscle growth?

Should we use different rep ranges for different lifts? If doing 5-rep sets on the bench press hurts our shoulders, should we use a higher rep range? If doing 12-rep sets of squats challenges our fitness more than our strength, should we use a lower rep range? And what about compound versus isolation lifts? Should we use lower reps for our compound lifts and higher reps for our isolation lifts?

Finally, what if we want to use a rep range that helps us gain both muscle size and strength? Does that mean we should use a mix of lower and moderate reps? For instance, lifting from 3 reps all the way up to 20 reps per set? Or is it better to use a rep range that’s halfway between strength training and hypertrophy training? For instance, doing 4–6 reps per set?

So, is there a hypertrophy rep range? And if so, what is it?

Outlift illustration showing a skinny man building muscle by lifting in the hypertrophy rep range.

A Moderate Rep Range is Often Best

Sets of anywhere from 4–40 reps will stimulate muscle growth quite well, but most research shows that doing 6–20 reps per set is the most efficient way to build muscle. Bodybuilders often use the middle of that range, favouring 8–12 reps per set.

Of all the studies comparing rep ranges for muscle growth, the most famous is the study by Brad Schoenfeld, PhD. It found that the same amount of muscle growth from doing seven low-rep sets as from doing three moderate-rep sets.

  • The strength training group did 7 sets of 3 repetitions. It took them 70 minutes to finish their workouts, and by the end of the study, they were complaining of sore joints and overall fatigue. Two of the participants dropped out of the study due to injuries.
  • The hypertrophy training group did 3 sets of 10 repetitions. It took them 17 minutes to finish their workouts, they were eager to do more lifting, they finished the study feeling fresh, and they gained the same amount of muscle mass.
Illustration of a man doing dumbbell biceps curls.

That caveat, of course, is that the group doing 7 sets of 3 reps gained quite a bit more 1-rep max strength, showing that low-rep training is indeed an important part of training for powerlifting. It’s just that for gaining muscle mass, using moderate rep ranges is much safer, more efficient, and easier to recover from, allowing us to stimulate more overall muscle growth.

The results of this study have been replicated several times (study, study, study). For instance, a recent study by Keitaro Kubo found that people doing 7 sets of 4 reps (7×4) on the bench press gained the same amount of muscle mass as those doing 3 sets of 12 reps (3×12). As we’d expect, the participants lifting in lower rep ranges saw greater improvements in their 1-rep max strength, but the moderate rep ranges proved to be a more efficient way to stimulate muscle growth.

One problem with these studies, though, is that they match training volume—total pounds lifted—instead of matching the number of challenging sets. If we look at a systematic review of 14 studies, we see that sets of 6–20 reps stimulate a similar amount of muscle growth per set, provided that we take those sets close enough to failure. That means that if we’re lifting within a moderate rep range, it’s better to count how many challenging sets we’re doing than to count how many pounds we’re lifting. These studies aren’t doing that. They aren’t matching the sets, comparing 3×4 versus 3×12 to see which stimulates more muscle growth, they’re matching the volume, comparing 7×4 versus 3×12.

These volume-matched studies clearly show that doing 3 sets of 12 reps stimulates as much muscle growth as doing 7 sets of 4 reps, but we don’t know how much muscle growth would be stimulated by doing 3 sets of 4 reps. After all, perhaps an equal amount of muscle growth was stimulated by the first 3 sets, at which point no more muscle growth was stimulated. That’s not completely crazy. We do see diminishing returns as training volume climbs higher. I’m skeptical of that, given that the training volumes weren’t that high, but even so, there’s only so much that we can conclude from volume-matched studies.

Are High Reps Good for Gaining Muscle Mass?

There’s quite a lot of evidence showing that high-rep sets can be good for building muscle. If we look at a study by Schoenfeld et al, we see that doing sets of 8–12 reps stimulates the same amount of muscle growth as doing sets 25–35 reps.

We have other examples of higher rep ranges stimulating plenty of muscle growth per set, too:

  • A twelve-week study comparing 3×20 versus 3×10 found that both rep ranges produced the same amount of muscle growth.
  • Another twelve-week study comparing 3×20-25 and 3×8-12R found that both rep ranges produced the same amount of muscle growth.
Illustration of a man with burning biceps after doing moderate-rep-range hypertrophy training.

So the good news is that if you’re forced to use light weights or bodyweight training to build muscle, you can delve into those higher rep ranges. It will hurt, yes, but you can absolutely build muscle that way.

However, lifting in higher rep ranges is a fetid nightmare, especially when doing the bigger compound lifts. Dr Schoenfeld noted that the participants doing sets of 25–35 reps were in excruciating pain and would often throw up after finishing their sets. That’s why most people prefer doing low-to-moderate-rep sets.

Are Low Reps Good for Gaining Muscle Mass?

Low-rep sets will stimulate muscle growth, but not as efficiently as moderate or high-rep sets. For every low-rep set that you do, you may only stimulate 50–80% as much muscle growth as you would by doing moderate-rep sets. This makes strength training an effective but inefficient way to build muscle.

The most controversial question, by far, is where the lower cut-off is. Lifting in higher rep ranges is so painful that most people won’t do it. It’s not a popular style of training. Nobody is really advocating for it. But lifting in lower rep ranges is quite pleasant and easy. Squatting for five reps is much easier than squatting for ten reps. But are low reps good for building muscle?

Outlift illustration showing a man doing a conventional barbell deadlift.

So, first of all, we do have some evidence showing that lower-rep sets don’t stimulate as much muscle growth:

  • In this study, the participants lifting 2–6 reps needed to do 24 sets of the squat and bench press to build as much muscle as the participants doing 8–12 reps for just 13 sets.
  • In this study, the participants lifting 2–4 reps for 3 sets gained less quad size than the participants lifting 8–12 reps for 3 sets.
  • In this study, the participants lifting 13–15 and 23–25 reps gained a significant amount of muscle size in most muscle groups, whereas the participants lifting 3–5 reps did not.

These findings indicate that heavy load training is superior for maximal strength goals while moderate load training is more suited to hypertrophy-related goals when an equal number of sets are performed between conditions.

Brad Schoenfeld, PhD

It’s important to note the one study by Mangine et al that showed greater arm growth from doing sets of 3-5 reps than from doing sets of 10–12 reps. Mind you, they were training their entire bodies, and the difference in muscle growth was only seen in their arms. If we compare muscle growth throughout their entire bodies, the effect disappears. But even so, this remains an example of a study that at the very least found equal muscle growth between lower and moderate rep ranges. This study appears to be an outlier, but until we have more research, it’s hard to say for sure.

When reps are low, the number of hard sets is not a good proxy for hypertrophy. Rather, when reps are low, total volume should be calculated.

Mike Zourdos, PhD

It seems like when we’re doing fewer than six reps per set, we have to match the volume—total pounds lifted—when comparing those sets with moderate rep ranges. And when we do that math, we see that the muscle growth being stimulated per set drops quite a bit. For instance, doing 225 reps for ten reps is 2250 pounds lifted, whereas lifting 275 pounds for five reps is just 1375 pounds lifted. That’s why it seems to take nearly twice as many low-rep sets to stimulate as much muscle growth as a single moderate-rep set.

With that said, these differences in volume really only start to become significant when comparing rather different rep ranges. It’s possible that doing a set of five reps stimulates about as much muscle growth as doing a set of six reps. And even if it doesn’t, the difference is surely quite small. There’s no magic point as we move from six to five reps where all of a sudden people switch from gaining pure muscle size to gaining pure 1-rep max strength.

On the other hand, even small differences in rep ranges could result in different amounts of muscle growth over the longer term, and that could apply even within moderate rep ranges. It’s possible that doing sets of seven reps would eventually yield more muscle growth than doing sets of six reps. It’s possible that doing sets of eight reps could eventually stimulate more muscle growth than doing sets of seven reps. This is the point that Mike Zourdos, PhD, makes in Monthly Applications in Strength Sport:

While there isn’t necessarily sufficient evidence to say that the 15 reps would yield greater hypertrophy than the 6-rep example when sets are equated, without long-term data, it’s worth considering differential hypertrophy outcomes could occur over the very long term.

Mike Zourdos, PhD

There’s nothing wrong with lifting in lower rep ranges, but it might require doing more sets to stimulate an equivalent amount of muscle growth. And since low-rep sets tend to benefit from longer rest times and can be somewhat difficult to recover from, using lower reps comes with an opportunity cost. Plus, the main benefit of lifting in lower rep ranges is that it gives us practice lifting close to our 1-rep max. That’s incredibly important for powerlifters, but for people who are more interesting in becoming bigger, stronger, fitter, and better looking, that benefit disappears. For non-powerlifters, there’s no major advantage to lifting in those heavier rep ranges.

Which Rep Range is Best for Gaining Strength?

A bigger muscle is a stronger one, so any rep range that helps us build muscle will also help us gain strength. However, if you define strength by how much you can lift for a single repetition, then sets of 5–10 reps are best for building muscle in a way that will improve your 1-rep max.

Many people are simply interested in building bigger muscles. I can certainly relate to that. When I was skinny, I was far more desperate to get bigger than I was to get stronger. Even just comparing the popularity of bodybuilding versus strength training, we see that bodybuilding is several times more popular:

Google searches for strength training (blue) vs bodybuilding (red).

But even so, most of us also care at least a little bit about improving our general health, general fitness, and general strength. Lifting in moderate rep ranges is great for improving our general health and fitness. Lifting more total pounds per set, putting greater demands on our cardiovascular systems, and building more muscle mass are all great for our health and fitness. But what about our general strength?

Powerlifters measure their strength by how much they can lift for a single repetition—their 1-rep max strength. This is a special skill that we can practice by lifting closer to our 1-rep max. That’s why strength training and powerlifting training use lower rep ranges. But that doesn’t make us stronger, per se, it just helps us specialize our strength for powerlifting.

This can get confusing because bodybuilding and hypertrophy training have no official way of measuring strength. No official lifts, no rules about how to perform them, and no 1-rep max test. For that, people often turn to powerlifting, thinking that they need to test their 1-rep maxes to see how strong they are. And to improve their skill at lifting 1-rep maxes, they turn to strength training, as they should—that’s what it’s for.

However, this can lead people to assume that heavier rep ranges are better for developing strength, whereas moderate rep ranges are better for developing size. That’s not quite right. Muscle size is almost perfectly correlated with muscle strength, so the rep ranges that are best for helping us gain muscle size are also the rep ranges that are best for helping us become stronger. If our goal is to become generally stronger, we can usually do that more efficiently by lifting in the 6–20 rep range. As we get stronger within that rep range, we’re getting stronger in general, too.

Illustration of a man doing a conventional deadlift.

However, there’s another important aspect to general strength. A bigger muscle is a stronger muscle, yes, but we also need to make sure that we develop the relevant muscles. For instance, doing biceps curls will make our biceps bigger and stronger, but that won’t necessarily help us deadlift more weight. For that, we would need to build bigger hips, spinal erectors, and forearms. This is the problem that a lot of casual bodybuilders run into. It’s not that they’re “big but weak,” it’s that they aren’t big in the right places.

To become generally strong, then, we need to become better at lifts that develop our general strength. If we want to be able to pick up heavy things and carry them around, we might want to do conventional deadlifts and loaded carries. If we want to lift things overhead, we should be doing lifts like the overhead press. If we want to be able to carry stuff in front of our bodies, we might want to spend more time doing front squats. And if we want to be able to pull our bodies over things, we can do chin-ups.

Illustration of a man doing a chin-up.

So building general strength has more to do with building bigger muscles by doing the big compound lifts, less to do with lifting in lower rep ranges. The exception to that rule is powerlifting, where our strength is measured by how much we can lift for a single repetition. For everyone else, though, we can measure our strength by how much we can lift in a variety of different rep ranges. For instance, someone who can bench 300 for a single is similarly strong to someone who can bench 275 for 5 reps or 225 for 10 reps.

Perhaps more importantly, going from benching 185 pounds for 10 reps to benching 225 pounds for 10 reps shows a significant improvement in strength. That means there’s no need to train for or test our 1-rep max to gauge our strength.

Are 5×5 Routines Good for Gaining Muscle Mass?

5×5 routines are good for building muscle, but doing slightly more reps is even better. For instance, you could stimulate a similar amount of muscle growth by doing 3 sets of 10 repetitions as you would by doing 5 sets of 5, keeping your workouts shorter or freeing up more time for other lifts.

5×5 routines are commonly used during the mass phases of strength training programs because they allow us to lift fairly heavy (over 80% of 1-rep max) while still getting in enough overall volume to build muscle mass. And they’re popular because they work. You can indeed build muscle with 5×5 workouts.

Now, most research shows that we build more muscle per set when doing at least 6–8 reps per set, and that may be true. But sets of five reps are right on the cusp of being ideal for gaining muscle. When we’re talking about small differences in rep ranges, the difference in muscle growth will likely be similarly small.

Illustration showing a powerlifter doing a low-bar back squat.

In the latest issue of Monthly Applications in Strength Sport, Greg Nuckols said that he suspects that sets of 3–5 reps aren’t as good at stimulating muscle growth as moderate-rep sets, but that they’re not that far off, either. We don’t necessarily need to do twice as many sets, but we might need to do a couple of extra sets.

My personal hunch is that low-rep sets (of around 3-5 reps) are a bit less efficient for muscle growth on a per-set basis, but not quite to the point of needing to equate for volume load.

Greg Nuckols, MA

For instance, instead of doing 3 sets of 12 reps (3×12), we might want to do 5 sets of 5 reps (5×5). This is the approach we see in 5×5 programs, such as StrongLifts 5×5, and it’s why people will often argue that it stimulates more muscle growth than lower-volume programs like Starting Strength, which uses 3 sets of 5 reps (3×5).

Now, does that mean that 5×5 workout programs are good for gaining muscle size? Not necessarily. Doing 5×5 on the bench press might stimulate the same amount of muscle growth as doing 3×12 on the bench press, yes, but we also need to consider that these lower-rep sets require longer rest times, that they can be harder on our joints, and that we need to do more total sets to get an equivalent benefit. As a result, someone might spend half an hour doing their 5×5 on the squat, finish it already feeling a bit tired, and then have to grind through a 5×5 on the bench press and then row. The full workout takes 60-75 minutes, they’ve only done three lifts, and they feel like they’ve worked pretty hard.

Graph showing triceps growth from doing the bench press and triceps extensions.

The problem is, we’re spending so much energy on so few lifts that it becomes hard to work all of our muscles. For instance, let’s consider the bench press. The bench press is great for stimulating growth in our chests and shoulders, but it’s not ideal for stimulating growth in our triceps (study). If we want to maximize the growth of our triceps, we also need triceps extensions. It’s certainly possible to do 5×5 on the bench press and then move on to triceps extensions afterwards, and then lateral raises, and so on. But you can imagine how those workouts could get quite long.

Plus, this is assuming that muscle growth is maximized with just three sets per muscle group per workout. If we look at the ideal training volume for gaining muscle size, that doesn’t seem to be the case. It seems that muscle growth is maximized by doing 4–8 sets per muscle group per workout. That means that to maximize muscle growth, we wouldn’t be doing five sets of five, we’d be doing 6–10 sets of five. When volumes start climbing higher like that, it can pay to have an easier and more efficient way to stimulate muscle growth.

If we compare to how a bodybuilder trains, we can see the advantage of using moderate rep ranges. An intermediate bodybuilder might spend ten minutes doing 3×12 on the bench press and then another ten minutes doing 3×15 skull crushers. Within that same 20-minute timeframe, they’ve stimulated the same amount of chest growth, they’ve doubled their triceps growth, and they’re probably still feeling fairly fresh. It’s an easier and more efficient way of building muscle.

So it’s not that we can’t build muscle with 5×5 strength training programs, it’s just that hypertrophy training (aka bodybuilding) programs help us gain muscle size faster and more efficiently.

Is There A Hypertrophy Rep Range?

Sets of 1–5 stimulate less muscle growth than sets of 6+ reps, making them less efficient. And sets of 20+ reps are more painful, making it difficult to push ourselves hard enough to stimulate growth. That’s why 6–20 reps is often dubbed the “hypertrophy rep range.”

Illustration of a man with burning biceps flexing.

According to experts like Greg Nuckols, MA, sets of 4–40 reps are ideal for gaining muscle mass. According to others, such as Mike Israetel, PhD, sets of 5–30 reps are best for building muscle. We also have researchers like James Krieger, MS, favouring sets of 8+ reps. Still, all these hypertrophy rep ranges are essentially the same, and they become even more similar once we start putting them into the context of a good bodybuilding/hypertrophy program.

The hypertrophic stimulus and fatigue generated by each set between roughly 5 and 30 reps are about the same. Volume and intensity cause growth and fatigue, and when one goes up per set, the other goes down to preserve a roughly even effect.

Mike Israetel, PhD

When we’re doing sets of 1–5, the sets tend to be harder on our joints and connective tissues, they can have higher rates of injury, and they can take longer to recover from. There are problems with doing sets of 20–40 reps, too. First, we need to take them closer to muscular failure to reliably provoke muscle growth. Second, taking high-rep sets to failure is so painful that it can make people vomit, give up, or hate training. And third, higher-rep sets can cause a tremendous amount of muscle damage, making our workouts harder to recover from.

Since training with more moderate loads may be more time efficient and carry a lower injury risk, you’re best off spending most of your training time in the more moderate load range, with low reps mixed in for strength benefits, variety, and personal preference.

James Krieger, MS

Finally, we have a new systematic review from Dr Brad Schoenfeld concluding that any load over 30% of our 1-rep max can be heavy enough to stimulate muscle growth, provided that we bring our sets close enough to failure. However, he notes that low-rep sets stimulate less muscle growth per set while inflicting greater stress on our joints, whereas higher-rep sets take longer and are quite a bit more painful. As a result, he recommends defaulting to moderate rep ranges when training for muscle growth.

So although sets of 4–40 can be good for stimulating muscle growth, it’s often easier to build muscle if we spend more of our time lifting in the 6–20 rep range. And even within that shrinking rep range, different lifts respond better to different rep ranges, narrowing it further still.

Different Rep Ranges for Different Lifts

When we’re picking our rep range, our goal is to challenge our muscles with enough overall volume, to make sure that we aren’t being limited by our cardiovascular fitness, and to avoid injury and pain. As a general rule of thumb, that’s why moderate rep ranges are so convenient. But, as you can imagine, different lifts challenge us in different ways.

When we’re squatting and deadlifting, we’re engaging tons of muscle mass, lifting heavy loads, sharing the load between several joints, and moving the weight through a large range of motion. It’s easy to be limited by our cardiovascular systems. As a result, it’s often better to use lower reps: 4–10 reps per set.

When we’re bulking up our necks, though, our neck flexors and extensors are rather small. We can do higher reps without being limited by our fitness, it doesn’t tend to hurt that much, and it might be safer. So with neck training, we might want to use higher reps: 15–40 reps per set.

So instead of doing 6–20 reps for every lift, we want to use different parts of the rep range at different times. Lower reps tend to be ideal for the bigger compound lifts, giving us loose rep range recommendations for our five big hypertrophy lifts of, say:

Illustration of a man doing a front squat

And then the ideal rep range climbs higher for assistance and accessory lifts, which are lighter, less fatiguing, and can sometimes tolerate a bit of technique breakdown. Here are some loose recommendations for some common isolation lifts:

  • Biceps Curls: 8–15 reps per set.
  • Rows: 8–15 reps per set.
  • Dips: 8–15 reps per set.
  • Dumbbell Bench Press: 8–15 reps per set.
  • Skullcrushers: 8–15 reps per set.
  • Romanian Deadlifts8–15 reps per set.
  • Zercher Squats: 8–15 reps per set.
  • Lateral Raises: 10–20 reps per set.
  • Overhead extensions: 10–20 reps per set.
  • Push-Ups: 10–30 reps per set.
  • Wrist curls: 12–30 reps per set.
  • Neck curls: 15–30 reps per set.
Illustration of a man doing a 3-point dumbbell row.

Genetics and personal preference will factor into what rep ranges you prefer, too. Some people’s shoulders ache when they bench too heavy, others when they bench too light. Some people’s lower backs get beat up with low-rep sets of deadlifts, whereas others get winded before they can finish a set of ten. There’s plenty of room for personal preference.

So, How Many Reps to Build Muscle?

Doing around 6–20 reps per set is usually best for building muscle, with some experts going as wide as 5–30 or even 4–40 reps per set. For bigger lifts, 6–10 reps often works best. For smaller lifts, 12–20 reps often works better.

Illustration showing a skinny man becoming muscular by lifting in the moderate repetition range.

If you have sore joints, it can help to use higher rep ranges, doing 12–40 reps per set. And if you’re interested in improving your 1-rep max, you might want to favour lower rep ranges, doing 4–10 reps per set. Otherwise, it’s best to spend most of your time doing 6–20 reps per set, occasionally going as low as 4 reps and as high as 40 reps per set.

Cover illustration of the Outlift intermediate bulking program for naturally skinny guys.

If you want a customizable workout program (and full guide) that builds these principles in, check out our Outlift Intermediate Bulking Program. Or, if you’re still skinny, try our Bony to Beastly (men’s) program or Bony to Bombshell (women’s) program. If you liked this article, I think you’d love our full programs.

Shane Duquette is the co-founder and creative lead of Outlift, Bony to Beastly, and Bony to Bombshell, and has a degree in design from York University in Toronto, Canada. He's personally gained 65 pounds at 11% body fat and has ten years of experience helping over 10,000 skinny people bulk up.

Marco Walker-Ng is the co-founder and strength coach of Outlift, Bony to Beastly, and Bony to Bombshell, and is a certified trainer (PTS) with a Bachelor's degree in Health Sciences (BHSc) from the University of Ottawa. His specialty is helping people build muscle to improve their strength and general health, with clients including college, professional, and Olympic athletes.