The Pump: Broscience Or Legit Muscle Builder?

Man Pumped Muscle Dumbbell Row
The research is in and muscle pumps are legit. Find out just how much they can help you improve muscle gains. This feature includes a complete pump-inducing workout plan.

"Remember bodybuilding, and I stress (this) over and over, is mainly working for the pump and doing repetitions." - Jay Cutler


"The greatest feeling you can get in a gym, or the most satisfying feeling you can get in the gym is the pump." - Arnold Schwarzenegger

"You pump up, it goes down, a little bit stays. You pump up next time, a little more stays. And gradually that accumulates over time and that creates your look." - Frank Zane

Is the pump nonsense, or is it worth your time? That is the question.

In years past I dismissed the pump completely. I thought it was a complete waste of time and utter broscience. When someone would ask me if the pump was at all worthy of consideration I would beat the same drum:

Stick to progressive overload and don't worry about it.

Recently I learned that there is a fair amount of science backing up pump sets. During the last decade evidence has accumulated supporting the theory that blood flow is a major regulator of glucose uptake in muscle tissue. There is also research indicating that blood flow impacts muscle protein synthesis. It does so by increasing transport of free amino acids into muscle cells. This, in turn, stimulates protein synthesis.

This notion is supported by the high correlation between blood flow and fractional synthesis rate (FSR).

"In summary, the results of our study demonstrate that net protein synthesis during amino acid administration can be doubled by previous performance of heavy resistance exercise. Moreover, the data suggest a link between the stimulation of protein synthesis after exercise and an acceleration in amino acid transport. The greater rate of transport after exercise may be due to the increase in blood flow." [1]

Long story short, extended pump sets increase blood flow to muscle tissue, apparently creating potential for muscle tissue size increases because of their impact on protein synthesis.

The pump as a stand alone training tool

We have established that the pump is indeed a valid training tool, but it should be stressed that hypertrophy (the muscle building process) is a very complex process and will require a multitude of methods if maximal size is the end goal. Research shows us that the pump creates a potential for more size, but it is not the only muscle building mechanism.

If one were to only train for the pump, and ignore all other research on the muscle building process, it is unlikely that a substantial amount of muscle mass would be built. The pump should be used in concert with other muscle building tools, and not used instead of them. Think of muscle pumps as gains amplifiers rather than prime stimulators.

The human body is very efficient at acclimating to external stimulus. If you started your training with a 95 pound bench press and never pushed for weight advancement, choosing only to focus on pump sets, it is likely that you would add some muscle size for the first several months. After that point, once adaptation to this specific demand has taken place, muscle gains would slow dramatically.

How do we know for sure? Let's look at the evidence. I implore you to draw your own conclusion from the following information.

SAID principle. The SAID principle, specific adaptation to imposed demands, is very real. If you cease to challenge your body in new and more intense ways, your muscles will have no reason to grow. You can certainly continue to use the same weight and add more reps and/or sets, but this approach will have its limitations.

It is theoretically possible to start with 95 pounds on the bench and only increase the sets and reps performed. For example, a trainee could begin with 5 sets and push them for as many reps as possible. This would be a quality starting point, and would likely lead to a muscle pump.

From there extra sets could be added. Reps could be added as well, but it likely wouldn't take more than several months for a bench press program like this to reach critical mass. By this I mean once you are performing 8, 9 or even 10 sets for as many reps as possible it becomes extremely difficult to add more. You will either run out of time at the gym, or run out of energy.

At this point drop sets, rest-pause training or other advanced training techniques could be implemented. But if you follow this path of only chasing the pump, there is a finite amount of volume/drop sets/etc. you can add before you reach your limit. (Unless you want to live in the gym for 2-3 hours per day chasing the pump)

How long would it take you to max out set and intensity additions while sticking with the same weight? Probably not long unless you are superhuman or independently wealthy and don't mind training for hours on end. Even in extreme cases where a trainee chases only set additions, somewhere during the first year of trainee he would need to turn his focus over to progressive overload. Set/volume additions can only be done for so long. They are finite. On the other hand, progressive overload can be chased virtually ad nauseam.

It is certainly possible to work up to 15 sets of bench press using 95 pounds. Would this build muscle? Yes, of course. Would you be building muscle at an optimal rate? Highly unlikely. A stronger muscle is a bigger muscle. Would it not be better to use the pump along with progressive overload? I think the answer is obvious here. The body of research on muscle hypertrophy backs this conclusion.

When you reach this set and volume limit, and can no longer stand to add more work because of time or energy constraints, gains will slow substantially because the stimulus is not changing. The body will adapt, and no further challenge will lead to trivial gains. Either that or the body will break down because of the brutality involved with this high volume, high rep, super-intense style of training.

It becomes apparent to me, when looking at the finite nature of volume additions in light of the SAID principle, that the pump must be used in addition to other hypertrophy methods and not as a stand alone tool. If you want to forsake all other muscle building gold standards, such as progressive overload, and simply find more creative ways of challenging your body using the same weight, I'd love to hear your story and see if you achieved any substantial amount of results.

Where are the weak bodybuilders? There are none. In fact, I never met a lifter with an appreciable amount of muscle size that hadn't accrued a substantial amount of strength. This doesn't mean they are powerlifter strong, but these guys are certainly a lot stronger than when they first started pushing around the iron.

You often hear experienced lifters talk about chasing the pump instead of "heavy weight." Jay Cutler talks about this in his video here at Muscle & Strength.

Let's put Jay's pump talk in perspective by looking at his overall strength levels. In a recent article (June, 2014) written by Jay Cutler [2], he makes the following statements:

"The best I ever did on the flat bench was 550 for 2 reps."

"At 19 I remember squatting with close to 700 pounds for a couple reps, and the reps were always ass-to-the-floor."

"I've done 405 for 8-10, and I can do 365 for 10 at any back workout." Note: Jay Cutler was referencing his barbell row strength.

Neither Arnold Schwarzenegger or Frank Zane were weak either. Arnold had Herculean strength (sorry Lou Ferrigno), and I have personally had the pleasure of talking with Mr. Olympia Frank Zane about his early strength training days. He was very strong before he made the switch to a pump-focused method of training.

Each of these Olympians, despite a later focus on chasing the pump, built an incredible strength base before doing so. What does this tell us? That strength plays a vital role in muscular development and should be combined with the pump for maximal results.

Over the course of the last 28 years I have had the opportunity to speak with hundreds upon hundreds of muscular lifters. These individuals include natural pros, top-level fitness models, and even female Olympians. Despite the fact that many of them make similar statements, like I don't focus on heavy lifting or chasing PRs, each of them is insanely strong in their own right.

What is going on here? The answer is simple in my book. Each of these lifters built a muscle base using some form of progressive overload. When the demands of heavy lifting started to punish them physically, they sought out other ways of challenging their bodies other than straight progression.

By and large, bodybuilding has yet to embrace the concept of intensity periodization. As a result, it is quite commonplace to see experienced lifters move away from a singular focus on progressive overload. They must, to save their body wear and tear.

It should be noted that these physique athletes are still tossing around more weight during their pump sets than most of us are using during our heavy sets. All things are relative, and this reality must not be ignored.

The "other" science of muscle building

Muscle pumps are far from the only lifting tool backed by research. Science also tells us the following are important aspects of hypertrophy:

  • Heavy sets (80-85% one rep max range), which recruit maximal muscle fibers from the first rep
  • Progressive overload (strength increases) [3]
  • Maximizing sets (pushing sets for as many reps as possible) [4]

Extreme muscle pump

5-8 rep range. Heavy sets will recruit maximal muscle fibers simply because of the weight involved. Research shows us that sets involving 80 to 85% of your one rep max (5-8 rep range) tend to recruit a near-maximal amount of muscle fibers. Simply stated, nearly every rep will involve maximal fiber recruitment.

It should also be noted that of the 2 types of muscle fibers (types I & II), type II fibers generate the most force and have the greatest potential for size increases. Type II fibers also require a substantial amount of weight to become activated, making lower rep sets a muscle building tool that must not be discounted.

Type II muscle fibers are actually comprised of  sub-categories, the 2 notable being:

  • Type IIA - Require slightly lighter weight than Type IIB fibers to be recruited. In the case of most muscle building programs, you will utilize conventional rep ranges (8-12) to activate these fibers.
  • Type IIB - Requires very heavy weight to be activated. In most case this involves sets around the 5-8 rep range.

As you can see, low rep and conventional rep sets work in concert to target Type II muscle fibers, which again, have the greatest potential to create muscle size increases.

Maximal reps per set. Another major factor leading to improved muscle fiber recruitment is relative set duration. Simply stated, the closer you push a set towards failure, the greater number of muscle fibers you recruit.

This practice transcends rep ranges. By this I mean that regardless of the rep range used, as long as you are pushing a set close to failure, you are recruiting as many muscle fibers as possible.

Understand there is no need to train a set to failure.This does not increase fiber recruitment. I personally recommend pushing each set for as many reps as possible, stopping a set when you feel like you might fail on the next rep, or when your form starts to noticeably deteriorate.

Training to failure only adds risk, and increases the potential for injury. Your form is bound to breakdown on the failing rep. With that said, some exercises you can push to failure without adding much risk. Each exercise is different. Use your best judgment, but understand that training to failure isn’t a requirement for muscle growth.

There have been several studies that indicate the greater the effort there is on a rep, the greater the response. Dr Ralph N. Carpinelli, a faculty member at the Human Performance Laboratory at Adelphi University in Garden City, New York, completed an exhaustive meta-analysis on the science of weight training and gains. [4]

Dr. Carpinelli had this to say:

“The size principle states that when the central nervous system recruits motor units for a specific activity, it begins with the smallest, more easily excited, least powerful motor units and progresses to the larger, more difficult to excite, more powerful motor units to maintain or increase force.”

Why does any of this matter? Simple...more intense reps activate more muscle fibers. The deeper you venture into a set, the more muscle fibers you recruit because the reps become more difficult to complete.

The pump "plus" - building a well-rounded muscle building plan

So in this article we have established several things about the muscle building process:

  1. The pump is a quality muscle building tool.
  2. Chasing muscle pumps alone is unlikely to lead to optimal hypertrophy.
  3. Heavy and conventional set training work in concert to stimulate Type II muscle fibers, which have the most potential for growth.
  4. Pushing sets for as many sets as possible encourages recruitment of more muscle fibers.

To maximize the muscle building progress, we should take each of these research-based principles seriously. One tool alone can build muscle (to varying degrees, based on that individual tool), but each of these tools working together has the greatest potential to forge gains. At the very least, they provide a quality starting point. Training can be evolved from here based on needs and body feedback.

So while the pump is an effective muscle building tool, it makes little sense to make it your only focus. Without a strength base, and without a quality amount of workout intensity (pushing a high percentage of sets for as many reps as possible), the pump won't yield the quality amount of muscle mass you are after.

Intense chest pump

Structuring a workout for major body parts

When attacking a major muscle group, it makes sense to first target your Type IIB fibers with heavy weight in the 5-8 rep range. After this point you can shift your focus to Type IIA fibers and more conventional rep ranges (8-12ish). This combination creates a quality potential for muscle growth, and is a highly effective base.

To amplify the results from these sets, make sure that they are pushed for as many safe reps as possible. Never jeopardize form for an extra rep. Live for progress, but not when extra risk is involved.

After you have challenged a muscle group in these 2 rep ranges, it's time to move on to pumping work. Pump work can take many forms. It can involve:

  • Volume sets, say 5 sets x 8-15 reps with a limited amount of rest between sets.
  • Burn sets, which are detailed in this Power, Muscle, Burn workout.
  • Supersets, trisets, giant sets or drop sets, which push a muscle without rest into the pain and pump zone.

Minor muscle groups are often taxed heavily while performing compound movements. It can be quite difficult to train smaller muscle groups using the 5-8 rep range. When training minor muscle groups, stick with more conventional rep ranges and round out your session with pump work.

Here are a few sample workouts that involve pump work, one for chest, quads and a sample calves program.

Chest workout with pump focus
Chest Pump Workout
Exercise Sets Reps
Bench Press 4 4-6
Incline Dumbbell Bench Press 3 8-12
Machine Chest Press 3 8-12
Pec Dec - 20 seconds rest between sets 5 10
Quads workout with pump focus
Quad Pump Workout
Exercise Sets Reps
Squats 5 5
Leg Press 5 10-15
Leg Extensions - Drop sets, run the rack. Perform as many reps as possible and keep dropping the weight by 10 pounds until you can't continue.  2 Drop set sequence
Calves workout with pump focus
Calves Pump Workout
Exercise Sets Reps
Seated Calf Raise 4 10-15
Superset - Standing Calf Machine 3 15
Superset - Jump Squats 3 20

Building a complete intermediate program

Lifting heavy week in and week out can take it's toll on the body. Still, the need for progressive overload remains. Instead of abandoning the heavier side of training altogether as you progress into your intermediate years, I recommend using periodization.

This sample workout rotates between 3 distinct types of training:

  • Week 1 - Heavy training, 5-8 rep range
  • Week 2 - Conventional training, 8-12 rep range
  • Week 3 - Pump training, superset focus

Every set will be pushed for as many reps as possible. This will allow you to constantly challenge your body and push for progressive overload without training super-heavy each week.

Week 1 - Heavy training

Here is a sample schedule for week 1:

  • Monday - Lower Body A
  • Tuesday - Upper Body A
  • Thursday - Lower Body B
  • Friday - Upper Body B
Lower Body A
Exercise Sets Reps
Squats 3 5-8
Hack Squats 3 5-8
Romanian Deadlifts 3 5-8
Seated Calf Raises 3 8-12
Planks 3 60 sec
Upper Body A
Exercise Sets Reps
Bench Press 3 5-8
Barbell Rows 3 5-8
Single Arm Overhead Dumbbell Press 3 5-8
Weighted Dips 3 5-8
Barbell Curls 3 5-8
Lower Body B
Exercise Sets Reps
Front Squats 3 5-8
Leg Press 3 5-8
Wide Stance Good Mornings 3 5-8
Standing Calf Raises 3 8-12
Ab Wheel Rollouts 3 8-15
Upper Body B
Exercise Sets Reps
Incline Bench Press 3 5-8
Deadlifts 3 5-8
Military Press 3 5-8
Close Grip Bench Press 3 5-8
Weighted Chin Ups 3 5-8

Muscle pump

Week 2 - Conventional training

Here is a sample schedule for week 2:

  • Monday - Lower Body A
  • Tuesday - Upper Body A
  • Thursday - Lower Body B
  • Friday - Upper Body B
Lower Body A
Exercise Sets Reps
Squats 4 8-12
Dumbbell Lunges 4 8-12
Leg Curls 4 8-12
Leg Machine Calf Press 4 10-15
Planks 4 60 sec
Upper Body A
Exercise Sets Reps
Bench Press 4 8-12
One Arm Dumbbell Rows 4 8-12
Seated Arnold Press 4 8-12
Cable Tricep Extensions 4 8-12
EZ Bar Curls 4 8-12
Lower Body B
Exercise Sets Reps
Leg Press 4 8-12
Hack Squats 4 8-12
Dumbbell Stiff Leg Deadlifts 4 8-12
Seated Calf Raise 4 8-12
Ab Wheel Rollouts 4 8-12
Upper Body B
Exercise Sets Reps
Incline Dumbbell Bench Press 4 8-12
(Weighted) Pull Ups or Lat Pull Downs 4 8-12
Upright Rows 4 8-12
Skullcrushers 4 8-12
Dumbbell Curls 4 8-12
Week 3 - Pump training

Here is a sample schedule for week 3. Keep rest in between superset combos to a maximum of 60 seconds.

  • Monday - Lower Body A
  • Tuesday - Upper Body A
  • Thursday - Lower Body B
  • Friday - Upper Body B
Lower Body A
Exercise Sets Reps
Superset - Squats and Leg Extensions 3/3 8/12
Superset - Hack Squats and Bodyweight Jump Squats 3/3 10/20
Superset - Good Mornings and Leg Curls 3/3 8/12
Superset - Seated Calf Raise and Bodyweight Rocking Calf Raise 3/3 12/20
Superset - Planks and Cable Crunches 3/3 60 sec/20
Upper Body A
Exercise Sets Reps
Superset - Bench Press and Cable Crossovers 3/3 8/12
Superset - Barbell Rows and Pull Ups 3/3 8/AMAP
Superset - Machine Overhead Press and Side Laterals 3/3 10/12
Superset - Skullcrushers and EZ Bar Close Grip Bench Press 3/3 10/15
Superset - Dumbbell Curls and EZ Bar Preacher Curls 3/3 10/10
Lower Body B
Exercise Sets Reps
Superset - Leg Press and Goblet Squats 3/3 12/15
Superset - Front Squats and Dumbbell Lunges 3/3 8/12
Superset - Reverse Hack Squats and Dumbbell Stiff Leg Deadlifts 3/3 8/8
Superset - Smith Machine Calf Raise and Standing Dumbbell Calf Raise 3/3 12/12
Superset - Ab Wheel Rollouts and Weighted Sit Ups 3/3 10/20
Upper Body B
Exercise Sets Reps
Superset - Incline Dumbbell Bench Press and Pec Dec 3/3 10/12
Superset - Seated Cable Rows and Lat Pull Downs 3/3 10/10
Superset - Military Press and Dumbbell Upright Rows 3/3 8/15
Superset - Close Grip Bench Press and Rope Cable Tricep Extensions 3/3 8/12
Superset - Drag Curls and Rope Cable Curls 3/3 10/12

Final thoughts

There is no single magical muscle building workout formula. You can build plenty of muscle without heavy, low rep sets, and you can build muscle without the pump. Progression and consistency will take you a long way, especially when a solid majority of these sets are pushed for as many reps as possible.

Arnold Schwarzenegger wasn't just a fan on the pump. He was also bear-strong, and made sure to push as many sets as possible to their limit.

"The last three or four reps is what makes the muscle grow. This area of pain divides the champion from someone else who is not a champion. That's what most people lack, having the guts to go on and just say they'll go through the pain no matter what happens." - Arnold Schwarzenegger

Once you push a set for max reps, it's quite easy to beat a muscle when it's down and go for an intense muscle pump. You can jump right into a superset, drop set, add in rest-pause volume work, or simply perform a burn set.

However you perform pump work, if you perform pump work, use it as the coup de grace (final death blow).

Note on AAS use as it relates to the pump

Prolonged AAS (androgenic anabolic steroids) use can lead to receptor desensitization. This receptor fatigue inhibits the gains experienced from steroids. Several scientific studies exist that reveal training helps to renew these desensitized receptors. Known steroid expert Dharkam had this to say about training intensity and receptor stimulation:

"Since muscle contraction is one of the main up-regulators of androgen receptors, the harder your muscle contracts, the more androgen receptors you'll get."

It goes without saying that pump training produces brutal muscle contractions. For this reason, "the pump" appears to be a more beneficial tool for enhanced bodybuilders.


1. Biolo, G. An abundant supply of amino acids enhances the metabolic effect of exercise on muscle protein, Am. J. Physiol. 273 (Endocrinol. Metab. 36): El22-E129, 1997

2. Cutler, Jay. 4x Mr. Olympia Jay Cutler's best lifts for every bodypart. Muscular Development, June 28th, 2014. 

3. Golberg, AL. Mechanism of work-induced hypertrophy of skeletal muscle. Med Sci Sports. 1975 Fall;7(3):185-98.

4. Carpinelli RN. The size principle and a critical analysis of the unsubstantiated heavier-is-better recommendation for resistance training. J Exerc Sci Fit 2008; 6: 67-86. (Available at: