Phase 1 of the P.B.S. model, the Primer Phase, is designed to create the greatest window of opportunity for you to make muscle-building progress long-term.

Before you keep reading, check out part 1 of the P.B.S. model.

The goal of the primer phase is to set you up for long-term muscle building. It is designed to create the greatest window of opportunity for you to make muscle-building progress long-term.

People tend to give up on building muscle for one of two reasons:

  1. They hit a plateau
  2. They get injured

These issues usually occur because of poor program design, crappy motor patterns, selecting exercises that create or reinforce muscle imbalances, or a lack of strategic variety in the program.

The P.B.S. system is designed to resolve all of these issues. It helps you to avoid hitting a plateau by strategically changing the training stimulus and helping to bullet-proof you against injury by teaching perfect exercise execution, building stability, structural balance, and strength.

The Primer phase is the critical first step in achieving all of this. The Primer takes a minimal effective dose (MED) approach to training volume. This creates a longer runway to utilize the powerful muscle-building potential of volume increase in later stages. A Primer phase really comes into its own though in its ability to fix weak links and improve the execution of all your lifts. This means you can build more muscle and reduce injury risk.

Recommended: Need help building muscle? Take our Free Muscle Building Course

By improving your execution, you are able to create a better growth stimulus on every single rep you do. Within your training, you should take the mindset that, ‘every rep is a growth opportunity’. The Primer phase teaches this concept and aims to develop your ability to get the most from the least. Making every set more effective means you can get a potent muscle-building stimulus with fewer sets. This increases your training efficiency and also opens up a wider window of opportunity to keep building muscle for longer.

The exercises selected for a primer phase all have a very specific goal. Fixing weak links is a vital element. Addressing these means you reduce your injury risk and also stop strength leaks causing your form to break down before the target muscle has been fully challenged. Often, I see guys stopping sets because their form failed not the muscle they were trying to train. When that happens, you have missed a muscle-building opportunity. To force a muscle to grow you want to stimulate and fatigue it so that the set stops because the muscle is the limiting factor.

By creating optimal mobility, stability, structural balance, and the skill to execute lifts perfectly you can keep tension on the target muscle, maximize the muscle-building stimulus, and see superior results. These components are all woven into the fabric of a Primer phase.

If you get a Primer phase right, it means all of your training after is more effective and that you are more resilient and can handle higher training loads. That adds up to more muscle long-term.

Related: The Importance of Coaching Yourself on Major Lifts

Woman setting up for a deadlift in a gym.

Programming a Primer Workout

A Primer phase workout can be broken into four fairly distinct sections. Each section aims to address one of the 4’s.

  1. Stability
  2. Skill
  3. Structural balance
  4. Strength in end ranges

The 4 S’s – An Overview

The first S, stability, is addressed within the warm-up. Primer phase warm-ups focus on developing mobility and stability.

The next section focuses on skill. Developing a skill is best done without excessive fatigue so, during this part of your session you should stay further from failure, take longer rest periods, and do more sets. This allows quality to be high on all of the skill-based work.

The goal of the third section is to create structural balance. This is usually a unilateral movement. On single leg work, this naturally includes a stability component too so you are reinforcing what you worked on in your warm-up.

Finally, a workout finishes with what I call a "strength output section." The goal of this section is to challenge the target muscle in its fully lengthened or shortened position (more on which one later) and learn to recruit and fatigue that muscle by taking sets to failure. To achieve this, select exercises that provide external stability. Towards the end of the session, fatigue is high and your ability to create stability yourself (internal stability) is diminished. Wasting energy on trying to stabilize at this stage is pointless and will take away from the goal of taking a muscle to momentary muscular failure. If you need to stabilize you’ll most likely find that you fail because of stability issues not because the target muscle has been maximally recruited and fatigued.

When it comes to muscle building, you want the muscle to be the limiting factor, not your ability to coordinate complex motor patterns. Early in the session, you engrain good motor patterns as a long-term investment in efficient training in future phases. At the end of the session, the goal is to create as much of a muscle-building stimulus in as stable of an environment as possible.

1. Stability

People often confuse stability and strength. Consequently, they try to fix stability issues with strength interventions. This is an inefficient approach.

Stability is your ability to resist force. Strength is your ability to exert force. Most gym rats have focused their attention on their ability to exert force. This makes a lot of sense when your goal is gaining strength and muscle mass. Most lifters are completely oblivious to the stability component. This is not a problem in the early days, but as the gap between your strength capacity and stability capability widens, it can become an issue.

Often people cannot reach their size and strength potential because their stability is inadequate. This lack of stability means that sets end because stability is the limiting factor, not the target muscle. This leaves the muscle undertrained. It’s like they have the horsepower of a race car, but the steering and tracking of a battered old rust bucket.

There are two types of stability:

  1. Internal
  2. External

Internal stability is your body’s ability to resist force and maintain your position in space. External stability is provided or created by an implement outside your own body.

When training your back, a chest-supported T-bar row provides much more stability than bent-over barbell rows. Likewise, when training legs, a leg press machine provides a lot more stability for you than a barbell back squat.

Your ability to create internal stability on exercises that don’t create stability for you will play an important role in you reaching your strength and size potential. You cannot fire cannons from a canoe. If you lack the ability to resist force and maintain proper joint alignment your force production capacity will suffer. If you lack the ability to stabilize a joint to allow for the target muscles to display their maximum force capacity then you will leave size gains on the table.

Many of my thoughts on stability were influenced by Dr. Jordan Shallow. He taught me that when developing stability there are two main methods you can use:

  1. Reducing the base of support
  2. Offsetting load

Changing the base of support is best illustrated by thinking of the difference between a Romanian deadlift and a single-leg Romanian deadlift. Rather than being on two feet, you are on one. As a consequence, the stability challenge on the working leg is significantly higher as it has to work overtime to resist force and keep you upright.

Offsetting the load when you perform an exercise is another way to challenge stability. To do this, only add load on one side of your body. For example, hold a dumbbell in the same hand as the front leg when performing split squats. The offset load can shift your center of mass and increase the stability challenge.

2. Skill

To maximally challenge a muscle, you need a sufficient skill level on an exercise to make the muscle the limiting factor. To achieve this, certain exercises/movement patterns will be a staple of a program for the entire P.B.S. sequence. I like to use "indicator" lifts during the duration of the Building phase. These lifts stay in the whole time and act as a good indicator of the overall success of the program. If performance on these steadily increases then you can be confident good things are happening.

I generally have 4 indicator lifts. These are:

  1. A squat pattern
  2. A hip-hinge/deadlift variant
  3. An upper body push
  4. An upper body pull

The exact exercise used is specific to the individual, but these 4 movement patterns are in every program.

During the primer phase, the groundwork is done on these movements. To achieve this the lift is programmed for several sets where the quality of execution is the focus. At this point, going to failure is avoided. Ingraining perfect form is the goal. This is better achieved by performing more sets with fewer reps a long way from failure than taking a couple of sets to failure.

I will often program these for 4-5 sets of 4-6 reps, leaving a couple of reps in the tank.

The rest of the Primer phase, however, operates at a higher relative intensity. Outside of the skill-based lifts, most sets are taken to, or very close to failure. This allows a significant muscle-building stimulus to be created with fewer overall sets.

Taking this MED approach to training volume by performing fewer sets per exercise, but pushing these lifts to technical failure creates a bigger window of opportunity to use increasing volumes as a method of progression in the Building phase that follows the Primer.

Muscular man doing incline machine chest press in a gym.

3. Structural Balance

Structural balance is about balancing your strength levels front to back and side to side. Developing an optimal ratio of push to pull strength or closing the gap in strength between your right and left leg for example. Doing this will help to manage your injury risk and allow you to get more from the building phase.

One of the factors that often holds back muscle-building progress is that a weak link in the chain prevents you from being able to fully challenge bigger, stronger muscles. Your body will not allow you to use loads and ranges of motion that represent a significant injury risk. Sadly, the ability to handle heavy loads across full ranges of motion is exactly what you need to grow.

Joint Movers vs. Joint Controllers

A car needs big horsepower and precision tracking to go fast! Your body is similar. To develop your physique, you need big strong prime movers and stabilizers. Another way to think of this is to think of muscles as joint movers and joint controllers. When you bench press, your chest, triceps, and anterior delts are the joint movers. Without adequate strength in the joint controllers for the bench press (e.g., rotator cuff, upper back, lats, biceps, etc.) you will not be able to perform optimally.

The primer phase picks specific exercises designed to eliminate these weak links. By creating structurally balanced strength levels throughout your body, you will be primed for growth because you can then challenge all of your muscles maximally through full ranges, safe in the knowledge that the opposing muscle groups are strong enough to do their job.

At the end of a Primer phase, you will have better technique, improved stability, structural balance, and you will also be much more robust. This makes you much less likely to pick up an injury that would keep you out of the gym. If you are out of the gym with an injury, you are not getting bigger!

4. Strength (End Ranges)

To finish a Primer workout, I program what I call strength output exercises. These exercises are chosen with the goal of you working to momentary muscular failure safely. The goal is to completely fatigue a muscle and teach yourself the ability to maintain textbook form as fatigue kicks in.

Selecting exercises that provide external stability such as machine-based movements is the best choice within this section.

Muscles tend to be strongest at their mid-range. They tend to weak at the extremes of range though (fully shortened or fully lengthened). Selecting exercises that really challenge the extreme points on the strength curve is, therefore, a key goal of the strength output section of a Primer workout.

If you are strong in the end ranges then the mid-range will take care of itself. Since these sets are done with extremely stable exercises, it is safe to push these to failure. This your chance to develop the capacity to get the most from the least. You will learn the skill of holding perfect form as failure approaches, keeping tension on the target muscle, avoiding momentum, and fully exhausting the muscle with just one, or perhaps, two sets. This minimum effective dose helps you make every set more effective but it also means you have a lot of scopes to ramp training volume up in subsequent phases.

Warm-Ups: The Gatekeeper to a Good Workout

A good workout starts with a good warm-up. A warm-up should accomplish two things:

  1. Prepare your body for performance
  2. Help prevent pain and injuries

Your warm-up should be specific to the upcoming workout and are a good opportunity to develop stability.

The drills you choose to implement should reflect the demands of the sessions and prepare you for these. A great warm-up signposts what you are planning on doing in your training session. Then, your training session should capitalize on this by further developing them. In time, this will reduce the amount of time needed for a warm-up.

Related: Warming Up For Dummies: A Lifter’s Guide to Injury Prevention

Using specific gatekeeper exercises can help to improve your warm-ups and workouts. These gatekeeper exercises are like tests that you have to pass to earn the right to move onto the main workout and load things up heavy. Incorporating gatekeeper exercises in the warm-up routines I write for clients usually means I am asking them to display mobility, control, and stability. These exercises are a better indicator of your readiness to train heavy than the fluffy activation/low-level strength work so many Instagram models promote. For example, band lateral walks do provide a strength challenge and activation drill for your glutes, but they don’t carry over that well to the true function of the glutes (and other muscles) in stabilizing the hip during gross movement. To target this function, you could add in an exercise that challenges your ability to create stability. A good choice in this example might be a single-leg RDL or hip airplane.

Utilizing gatekeeper exercises like this is a core element of the warm-ups within the P.B.S. framework. They help to develop stability which is great. They prime you for an effective workout. Even better, they show you have the requisite mobility and stability to push the envelope on the skill-based lifts in your workout.

Muscular woman doing lat pulldowns in a gym.

Example Primer Phase Workouts

Lower Body

Section 1 - Warm Up (Mobility and Stability Focus)

Exercise Sets Reps
A1. Couch Stretch  2 30 sec
A2. 90/90 Stretch  2 30 sec
A3. Single Leg RDL 2 8 each leg
A4. Counterbalance Squats 2 8

Section 2 - Skill Acquisition

Exercise Sets Reps Rest
Paused Front Squat 4 5 120 sec
Romanian Deadlift 4 6-8 120 sec

Section 3 - Structural Balance

Exercise Sets Reps Rest
D1. Ipsilateral DB Bulgarian Split Squat 3 10-12 each leg 90 sec
D2. Single Leg 45 Degree Hip Extension 3 10-12 each leg 90 sec

Section 4 - Strength Output

Exercise Sets Reps Rest
E1. Single Leg Extension 2 12-15 60 sec
E2. Eccentric Accentuated Lying Leg Curls* 2 8-10 each leg 60 sec
E3. Single Leg DB Calf Raise 2 12-15 60 sec

* Lift with two legs, lower with one for 5 seconds

Upper Body

Section 1 - Warm Up (Mobility and Stability Focus)

Exercise Sets Reps
A1. Foam Roll Thoracic Extension 2 30 sec
A2. Lat Stretch 2 30 sec
A3. Side-Lying Powell Raise 2 8 each arm
A4. Side-Lying DB External Rotation 2 8 each arm

Section 2 - Skill Acquisition

Exercise Sets Reps Rest
B1. Bench Press 4 5 120 sec
B2. Pull Ups  4 6-8 120 sec

Section 3 - Structural Balance

Exercise Sets Reps Rest
C1. One and Quarter Incline DB Bench Press* 3 8-10 90 sec
C2. DB Single Arm Rows 3 8-10 each arm 90 sec
D. DB Pullover** 2 10-12 90 sec

* Go all the way down, up a quarter of a rep, back down to your chest, and then all the way up

** Pause in stretched position for 2 seconds

Section 4 - Strength Output

Exercise Sets Reps Rest
E1. Seated Cable Fly 2 12-15 60 sec
E2. Rope Face Pulls 2 12-15 60 sec
F1. Chest Supported Rope Pressdowns 2 10-12 60 sec
F2. Single Arm DB Spider Curls 2 10-12 60 sec

It’s important to note that this is not the Primer workouts. They are just examples of how you can take the underlying principles and apply them. For example, the upper body session above would be a great choice for someone who wanted to improve their bench press but lacked thoracic extension.

As I identified earlier, a good warm-up should reflect the workout you are preparing for and the training session should mirror this back by building upon and engraining the elements addressed in the warm-up. For example, if thoracic extension is something you need to improve you would use drills in your warm-up to develop this mobility as I did in the above example. You would then progress to using exercises that trained you in this range to increase both stability and strength. By training these qualities within the session you help to consolidate the improved mobility created in the warm-up.

Related: Mobility 101: The Basics of Mobility (Plus a 15-minute Daily Mobility Routine)

Man holding a barbell in a front rack position in a CrossFit-style gym.

In time, this should mean your need for extensive warm-ups disappear and you retain good mobility at all times. Thus, your warm-ups can become much more streamlined and time-efficient. This will come in handy during the higher volume building phase when total training time increases somewhat.

When implementing this yourself establish what ranges of motion you need to improve. Use mobility and activation drills to create more range in your warm-ups then, place exercises in your workout to develop, reinforce, and strengthen these ranges during your training.

Here are some examples…

Lack thoracic extension?

Program some or all of face pulls, chest supported thoracic extension rows, and dual DB pullovers into your workout

Ankle mobility a limiting factor?

Include exercises that require you to work into full dorsiflexion and display stability and strength there. Including full ROM split squats with the intention of getting your hamstrings to sit on your calves at the bottom is a great strategy. Develop this by using a step to elevate the front foot so you can hit the full range. Each week reduce the height of the step slightly so that you can eventually achieve this with the front foot on the floor.

A lack of anti-rotation strength through your core a risk factor for lower back pain or injury?

Select exercises which will challenge this and strengthen you in this function. Good choices include staggered stance single arm DB rows, single-leg Romanian deadlifts, bird dogs, and Pallof presses.

Some of these exercises could actually be part of your warm-up and help bridge the gap from increasing mobility in a warm-up to strengthening ranges within the workout. On a day when a hip hinge like the Romanian deadlift is the indicator lift, you might need some hamstring mobility work to begin your warm-up. After this, a single-leg Romanian deadlift will help to further develop that but also train stability. Specifically, it will help to train your posterior oblique sling (a collection of muscles that help to provide lower back and hip stability and aid with rotation and anti-rotation). Selecting this exercise can improve stability and activate your lat, glutes, and hamstrings. This will prime you for a good performance on RDLs in the workout, but they also help train stability of the hip and your ability to control rotational forces. If this is something you need to develop then it’s a great two for one. Training efficiency at its finest.


Primer workouts provide an essential first step on the journey to maximal muscle building. They help create a firm foundation to build on. The bigger and stronger the foundations the bigger the building can be. This is true with building your body too. A properly performed Primer phase can literally prime you for months of effective muscle-building training. In the next installment, I will outline how to capitalize upon a Primer phase by creating an optimal building phase.

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