How Many Sets and Reps Should You Do?

Michael Berg, N.S.C.A.-C.P.T., and Brad Schoenfeld, C.S.C.S.

January 20, 2023 at 7:11 PM·13 min read

Wanna start a fight? Walk into a room filled with strength coaches, personal trainers, and exercise physiologists and ask, "How many reps should I do to build muscle?" Or, "What's the ideal number of sets?" Or, "What's the best way to gain muscle faster?" Then take cover.

If your ultimate strength training goal is hypertrophy (an increase in the growth of muscle cells and the size of muscle fibers—without increasing their number), you're prioritizing exercises and rep schemes that fatigue your muscles to ultimately build a bigger physique.

High reps, medium reps, low reps—each approach has been touted as a way to get stronger, faster. Stalwarts in the exercise business argue with deep-rooted passion, but incontrovertible conclusions are rare, leaving the average lifter wondering: Okay, How many reps should I do? How many reps for hypertrophy?

Here, we build separate muscle growth cases for high, medium, and low reps and render a verdict on which is the best choice for increasing muscle mass, also known as the hypertrophy rep range. The weight room will now come to order.

Here's a simple guide to matching sets and reps to your goals, whether you want to get stronger, lose your gut, or get huge.

Before we start, identify what your goal is and what type of athlete you identify as:

Muscle Endurance: long-distance runners, rowers, swimmers, cyclists, triathletes, cross-country skiers, and rock climbers
Strength: weightlifter, CrossFitter
Weight Loss: functional fitness athlete/weekend warrior
Power: long/high/triple jumper, sprinter, thrower (shot put/pitcher), wrestler, gymnast, speed skater, paddler (kayaker), rugby/football player
Hypertrophy: bodybuilder, hockey player

Difference Between Reps Versus Sets

The main difference comes down to rest. When you do an exercise concurrently, that's a rep. When you finish a cluster, that's a set, which is followed by a period of rest. When you're adapting your reps and sets scheme, you want to keep your goal in mind.

How to Target Different Fitness Goals

Hypertrophy training is meant for maximum muscle growth, so focus on high levels of volume in terms of sets and weight, but with fewer reps and minimal rest that result in increased muscle size.

Endurance training is meant to produce and maintain force for prolonged periods. You want to perform at higher intensities longer without becoming fatigued. Thus we focus on training with fewer sets but with higher repetitions of lighter weights with minimal rest.

Power training focuses on high force and velocity to increase power, typically by combining a strength exercise with a power move (i.e. a bench press superset with a medicine ball chest pass.)

Training Goal	Sets	Reps	Rest	Effort
Muscle (Hypertrophy)	3-6	6-12	2-4 min.	70% of 1 rep max
Strength	2-6	5-8	60 sec.	80% of 1 rep max
Weight Loss	3	10	90 sec.	Varies
Power	2-4	6-10 (explosive)	2-4 min.	90% of 1 rep max
Muscle Endurance	3-5	12-15+	30 sec.	60% of 1 rep max

How Many Reps Should I Do to Build Muscle?

The Argument for High Reps (15 or more)

When it comes to how many reps for hypertrophy, volume (think of total weight moved over all your reps) is more important than anything for adding muscle.

If you've ever tried a set of 15 or more reps, you know it can be difficult. If you're unaccustomed to training in this zone, you'll find your muscles fatigue quickly, and 40 pounds starts to feel more like 100 by the final rep.

While you’ll definitely get strong from heavy lifting, only focusing on big efforts isn’t the best method to pack on size. Long sets are a more effective way to break down a muscle group and spur growth and development.

Sets that stretch past 15 reps, though, have one major downside. The amount of weight you can handle isn't heavy enough to recruit fast-twitch type-2 muscle fibers.

Type-2 fibers are where the potential for growth resides, and they respond only to heavy weights—at least 75 percent of your one-rep max.

Prescription: Do 3 to 6 sets of 12 reps or more with 90 seconds of rest to bring on muscle exhaustion and open the door for growth.

The Argument for Moderate Reps (8 to 12)

The time-under-tension theory leads us to believe moderate-rep sets is integral for hypertrophy. At a cadence of two seconds on the concentric (lifting) action and two seconds on the eccentric (lowering) movement, your set will end up right in the middle of the optimum 30- to 60-second range for a given set of exercise.

When the set lasts longer than a few seconds, the body is forced to rely on the glycolytic-energy system, which leads to the formation of lactic acid.

You may think of lactic acid as a bad thing, since it's mistakenly associated with the muscle ache you feel days after a workout, but that soreness is actually a very fleeting reaction that's vital to new muscle-tissue production.

When lactic acid, or lactate, pools in large amounts, it induces a surge in anabolic hormone levels within the body, including the ultra-potent growth hormone and the big daddy of muscle-building, testosterone.

These circulating hormones create a highly anabolic state within the body and if you're after more muscle, that's exactly the state you want to be in.

The increased time under tension also leads to more muscle damage, imperative if you plan on getting larger any time soon. Theoretically, the longer a muscle is contracted, the greater the potential for damage to the tissue.

The moderate-rep range, when coupled with a challenging weight, will also bring about a much-desired condition: the muscle pump.

That tight, full feeling under the skin, caused by blood pooling in the muscle, has value beyond its ego-expanding qualities.

Studies have demonstrated that the physiological conditions that lead to a pump activate protein synthesis and limit protein breakdown.

Thus, more of the protein you eat goes toward muscle construction instead of being burned off for energy. In a scientific twist of good fortune, the fast-twitch fibers appear to be the biggest beneficiaries of this phenomenon.

Prescription: Do 3 to 6 sets of 12 reps with 30 to 90 sec. rest.

The Argument for Low Reps (5 or less)

Take a look around your gym, and you're likely to find an aspiring bodybuilder or two struggling through sets of squats or bench presses with weights at or near their one-rep maxes.

This method is a sure strength builder, and if you take a close look at any successful powerlifter, you'll notice the added mass in his frame.

However, low-rep training has one significant shortcoming: Muscle-fiber stimulation, and thus growth, is correlated closely to the amount of time a muscle is under tension.

Short, intense sets of 15 seconds or less will develop strength, but they simply aren't as effective in prodding a muscle to grow as sets of 30 to 60 seconds.

Prescription: Do 4-6 sets of up to 5 reps with up to 5 min. rest.

<p>James Michelfelder</p> — James Michelfelder

The Final Verdict on the Hypertrophy Rep Range

So, how many reps to build muscle? In the final analysis, substantial evidence argues that training in a moderate-rep range is the best way to build muscle mass.

It increases hormone response, spares protein, and provides the necessary time under tension to spark muscle damage. These benefits work in unison to get you from pencil neck to powerhouse in no time.

But does this mean you should ditch your low- and high-rep regimens? Certainly not. To make sure your body doesn't adapt to a particular regimen and stagnate, you need variety.

Cycle periods of low- and high-rep training into your overall program, while progressively trying to increase your strength and perfect your exercise form every time you lift.

How Many Reps Should I Do for Muscle Endurance?

High-rep training is an excellent means of increasing muscular endurance.

If you're after sports-specific adaptations such as a throwing arm for baseball that can hold out for more than half an inning or legs that will carry you to the finish line of a marathon, high reps can help.

Your muscles comprise a mix of fast- and slow-twitch fibers, but certain muscles are more geared toward endurance—like the upper back, quads, and the lower leg's soleus and plantaris—due to a higher distribution of slow-twitch fibers.

These predisposed slow-twitch muscles respond best to endurance-based work and longer sets. This can be taken a step further still by understanding that everyone has different levels of fast-twitch and slow-twitch fibers. Unfortunately, beyond those leg muscles, research is limited on what areas tend to have more slow- or fast-twitch fibers. So you'll have to treat yourself as a study of one and pay attention to what your body best responds to.

How Many Reps Should I Do for Strength?

If size is paramount, high reps won't get it done. In weight training, one adage has stood the test of time: To get big, you have to get strong. Taking that to an extreme, many lifters adopt a powerlifting approach, coupling very heavy weights with low reps. The neural output of those heavy lifts triggers the release of testosterone and human growth hormone.

Prescription: Do heavy sets of at least 4 to 6 sets of 5 to 6 (or fewer) reps with 3 minutes of rest.

Consider adding a burnout set at the end of your strength workouts: Shoot for at least 15 reps at about 60 percent of what you were lifting, and perform a single set of as many reps as possible until you hit technical failure.

How Many Reps Should I Do to Lose Weight?

When you want to burn calories, you don't need to go big on reps. You can achieve fat loss using heavy sets with 2 or 3 reps just as effectively as lighter sets of 20 reps—if you keep your rest brief.

For example, you can do a couple reps of heavy loads to help release more muscle-building, fat-burning hormones one training day. On an alternate day, pair non-competing lifts (like squats and pullups) into supersets to keep your heart rate up. Both will promote weight loss.

Prescription: For most traditional barbell and dumbbell exercises, do at least 3 sets of 10 reps, and keep rest intervals to 90 seconds or less.

As you lower your reps at heavier weights, add more sets. Overall, your goal is to increase the metabolic demand on your body. That comes from explosive movements, multi-joint exercises, and an elevated heart rate.

How Many Reps Should I Do to Build Explosive Power?

Training for explosive power is less about reps than it is about high force and velocity. Power, after all, is strength divided by time. This happens when you combine a strength exercise with a power move, such as performing a superset of a barbell bench press with a medicine ball chest pass. By performing, say, 5 reps of the bench and 10 with the chest pass, you’re best positioned to build explosive power.

Prescription: Do 2 to 4 sets of 6 to 10 explosive reps. Rest 2 to 4 min. for full recovery between sets.

How to Put this to Work: A Periodization Planner

If your haphazard training has been producing mixed results for a while now, consider periodizing your training.

Periodization is a system of training that organizes your workout into distinct cycles. Because each cycle has specific objectives, the number of reps for each varies sharply.

A typical periodization plan usually consists of three or four phases (depending on your goals):

Phase 1:

Preparatory, consisting of extremely high volume (15 or more reps, 3 to 5 sets) and low resistance.

Phase 2:

Hypertrophy, or growth, consisting of high volume (8 to 12 reps, 3 to 5 sets) and moderate resistance (50 percent to 75 percent of 1-rep max).

Phase 3:

Strength, consisting of moderate volume (5 or 6 reps, 3 to 5 sets) and heavy resistance (80 percent to 88 percent of 1-rep max).

Phase 4:

Power, consisting of low volume (2 to 4 reps, 3 to 5 sets) and very heavy resistance (90 percent to 95 percent of 1-rep max).

To build the explosive strength necessary for competition, athletes frequently use Phase 4, the power phase.

For the average lifter who's merely after more impressive weight-room results, Phases 1 through 3 are the way to go.

Keep reading for a simple three-month periodization cycle that can be used by both gym novices and grizzled veterans.

Get Bigger: The Sample Workout Program

This is arguably the perfect workout program to put on size.

Devote one month to each phase, gradually increasing resistance while decreasing the number of sets as the month progresses.

After the completion of this three-month cycle, actively rest (run, hike, play basketball, etc.) for a week or two before hitting the weights hard again. In the interest of simplicity, we have not changed the exercises between cycles.

Traditionally, however, the exercises do vary. Note how many reps to build muscle changes per phase. This will maximize growth by engaging the greatest number of muscle-fiber types.