How Diaphragm Function and Breathing May Improve Strength, Balance, and Recovery

Part 2: Improving Force Production and Movement From Head to Toe

Written by Michael Crawley, BSc, BPT, CSCS

Part 1 of this series looked at how jaw and tongue position influence force output and function. Part 2 turns to the diaphragm and breathing, and how they influence those same systems. As you'll see, good tongue and jaw function and good diaphragm function are closely connected, each affecting the other.

For a healthy individual, the diaphragm works through roughly 18,000 to 30,000 breaths a day. Breathing rate is largely involuntary, generated by the brainstem, but we can also consciously control it for more deliberate tasks.

Learning to influence your breathing can improve athletic performance, reduce some of the risks associated with aging, and support recovery. Before getting into that, here's a quick look at the anatomy involved.

Anatomy

The diaphragm's anatomy is complex, with connection points throughout the body. These connections include the sternum, ribs, and lumbar spine. The diaphragm also has openings that allow passage for major vessels such as the aorta and esophagus, creating a functional link between the thorax above and the abdomen below (Bordoni & Zanier, 2013).

Neural drive to the diaphragm comes from the cervical spine (C3, C4, C5), often remembered with the cue “C3-4-5 keeps the diaphragm alive.” Another key input comes from the vagus nerve, which helps regulate the depth and frequency of diaphragmatic movement, and plays an especially important role in the parasympathetic (“rest and digest”) side of breathing. These details set up the mechanisms discussed below, and help explain how to bias breathing for different outcomes.

Diaphragm, Valsalva, and Force Production

You've probably heard the cue “use your core” in gym and sport settings. It's not a particularly useful instruction, and it often gets misread as crunching the abdominals down and forward. That doesn't support what we call The Stack at Avos Strength, and it doesn't create an efficient system for force production.

As you inhale and exhale, the diaphragm's movement changes lung volume, which can be used to increase intra-abdominal pressure (IAP). This pressure allows the breath, abdominal muscles, and back muscles to work together, improving spinal stability and force production (Guo et al., 2021).

The Valsalva maneuver (VM) is a forceful exhale against a closed airway. Lifting heavy loads, or lighter loads close to failure, naturally creates a brief VM (Hackett & Chow, 2013). Combined with increased IAP, this is thought to improve spinal stability and allow for more efficient force production.

Disclaimer: Confirm with a healthcare provider that increasing training intensity or intentionally using the Valsalva maneuver is appropriate for you before adding it to your training.

A common strategy is to crunch the abdominals aggressively, which shortens the abdominal muscles and pulls the chest forward. Ironically, this limits the diaphragm's ability to descend and air to enter the thorax. To make this more concrete, here's a simple bracing sequence using the squat as an example:

1. Standing / prep: A gentle breath in, ideally through the nose.

2. Standing / prep: A slow, relaxed exhale through the mouth to generate abdominal tension.

3. Immediately pre-squat: A slight re-inhale to increase pressure against the abdominal wall.

4. Bottom position: An exhale against a closed mouth or pursed lips if the weight is heavy or fatigue is building.

For a step-by-step walkthrough, see this short video: The Myth of Bracing.

There's nuance here depending on load and volume. For example:

• At higher intensity (4 sets of 3 reps at 80% 1RM), you might reset your brace and breath every rep, or every second rep, using step 4 each time.

• At higher volume with lower intensity (3 sets of 6 reps at 70% 1RM), you might complete the first 3 to 4 reps without resetting, and without needing a forceful exhale against a closed mouth. Step 4 might only be needed on the last rep or two.

This sequence isn't necessary for every movement. Relaxed, lower-intensity work without a deliberate brace and Valsalva maneuver is a perfectly healthy strategy for exercises such as:

• Jefferson curl variations

• Spinal flow and rotational work

• Lower-intensity isometric work with continuous breathing

Now, from force production to the softer, broader effects of the diaphragm and breathing.

Further Roles and Influence

1. Proprioception, Balance, and Coordination

Proprioception (your sense of position in space), balance, and coordination are constant, everyday requirements, drawing on input from the inner ear, muscles, eyes, and nervous system. As people age, this information tends to travel less quickly and smoothly, which raises the risk of falls and related injuries. Balance exercises, walking on uneven ground, and visual exercises can all help offset that risk.

The diaphragm plays a role here too. Through its relationship with visceral fat, the diaphragm is itself a source of proprioceptive feedback (Bordoni & Zanier, 2013). Nazir et al. (2026) found that diaphragmatic breathing exercises improved balance confidence, reduced fatigue, and improved gait velocity in older adults.

The exercise used to produce that improvement was simple:

• Twice a week: 2 rounds of 6 minutes of focused diaphragmatic breathing.

• Diaphragmatic breathing: one hand on the chest, one hand on the belly button. Breathe in through the nose for 4 seconds, out through the mouth for 6 seconds.

No equipment, minimal time, and a meaningful reduction in fall risk. That's a good example of how much reach this type of training can have.

2. Restoration and Recovery

Many people are good at the hard side of training: pushing through a tough session, finishing a hard interval workout. Deliberate breathing plays an important role there, as discussed above, but recovery and downregulation matter just as much.

As mentioned in the anatomy section, the vagus nerve supplies the diaphragm and is tied to the rest-and-digest side of the nervous system. Slower, relaxed, mindful breathing after high-intensity activity can help activate the parasympathetic nervous system. Research has linked this to reductions in heart rate and respiration rate, and improvements in heart rate variability (Renaghan et al., 2023). See also Why Your Training Program Won't Work Without Sleep, Nutrition, and Recovery for more on why recovery deserves this kind of attention.

A simple way to introduce this: find a comfortable position (sitting, lying flat, or on your side) and take 10 to 20 relaxed breaths in through the nose and out through the mouth. Beyond supporting recovery, it also bookends the workout, creating a clear separation between the hard and the soft.

These are two of many ways the diaphragm and breathing influence training and daily life. There's a lot of literature on specific breathing styles (box breathing, Buteyko, and others), which can get overwhelming quickly. The simplest entry point is just adding short periods of focused, intentional breathing: relaxed in through the nose, slightly prolonged out through the mouth.

How to Apply This in Training

• Resistance training: Don't crunch the abdominals. Use a deliberate inhale-exhale to create stiffness before the movement. If appropriate, incorporate the Valsalva maneuver on higher-intensity efforts or more fatiguing higher-rep sets.

• Balance and proprioception: For older adults, add 2 sessions per week of 10 to 15 minutes of deliberate breathing practice to help offset age-related balance and fall risk.

• Restoration: Use relaxed breathing in a comfortable position after hard training to support recovery and help the body absorb the training stimulus.
  

Key Takeaways

• The diaphragm supports force production during strength training, largely through its role in generating intra-abdominal pressure.

• Deliberate breathing, not aggressive crunching, is what creates a stable, braced trunk.

• Diaphragmatic breathing can meaningfully improve balance and reduce fall risk in older adults, with just a few minutes of practice per week.

• Slow, relaxed breathing after training helps activate recovery through the parasympathetic nervous system.

• Simple, short breathing practices, done consistently, offer an outsized return relative to the effort involved.

Next Up

Moving down the body: the next post in this series will cover foot pressure and foot strength, and how they relate to force production, balance, and longevity, in the gym, in sport, and in everyday life.

References

Bordoni, B., & Zanier, E. (2013). Anatomic connections of the diaphragm: Influence of respiration on the body system. Journal of Multidisciplinary Healthcare, 6, 281–291. https://doi.org/10.2147/JMDH.S45443

Guo, J., et al. (2021). Embodiment of intra-abdominal pressure in a flexible multibody model of the trunk and the spinal unloading effects during static lifting tasks. Biomechanics and Modeling in Mechanobiology, 20(4), 1599–1626. https://doi.org/10.1007/s10237-021-01465-1

Hackett, D. A., & Chow, C.-M. (2013). The Valsalva maneuver: Its effect on intra-abdominal pressure and safety issues during resistance exercise. Journal of Strength and Conditioning Research, 27(8), 2338–2345. https://doi.org/10.1519/JSC.0b013e31827de07d

Nazir, S., et al. (2026). The effect of diaphragmatic breathing and diaphragmatic mobilization on physical performance, fear of falling, and quality of life in community-dwelling older adults: A randomized controlled trial. PLoS ONE, 21(1), e0339868.

Renaghan, E., et al. (2023). The effects of relaxation techniques following acute, high intensity football training on parasympathetic reactivation. Frontiers in Sports and Active Living, 5. https://doi.org/10.3389/fspor.2023.1267631

GLP-1 Medications and Weight Loss: What to Know Before You Start

Written by Evelyn Calado, MKin, CSCS, RKin

GLP-1 medications like Ozempic, Wegovy, Mounjaro, and Zepbound are everywhere right now. Your coworker might be on one. Your neighbour might be on one. There is a good chance someone in your gym is using one too.

The conversation around these medications is loud. Some of it is hype. Some of it is fear. A lot of it is missing important context.

This post is not here to convince you to use these medications, and it is not here to scare you away from them either. That decision belongs between you and your healthcare provider.

What I want to do is help you understand what the research says, especially as it relates to body composition, muscle loss, training, and long-term health.

As a kinesiologist, I believe movement, strength training, nutrition, sleep, and lifestyle habits are the foundation of long-term health. I also believe that mental health and psychological support are often left out of the weight loss conversation. For many people, body weight is connected to stress, trauma, emotional patterns, environment, and years of repeated dieting. No medication addresses all of that on its own.

That said, I am not here to judge anyone for using GLP-1 medications. If they are improving your health and quality of life, and you are using them under proper medical supervision, that is your decision to make.

But before starting, it is important to understand what these medications do, what they do not do, and what you need to do to protect your body while using them.

What Are GLP-1 Medications?

GLP-1 stands for glucagon-like peptide-1. It is a hormone your gut naturally releases when you eat. It helps regulate blood sugar, signals fullness to the brain, and slows how quickly food leaves your stomach.

GLP-1 medications work by mimicking that hormone and extending the fullness signal. This can reduce appetite, lower food intake, and improve blood sugar regulation.

Some of the most well-known medications include semaglutide, sold under names like Ozempic and Wegovy, and tirzepatide, sold under names like Mounjaro and Zepbound.

Tirzepatide is slightly different because it targets both GLP-1 and GIP receptors. This is one reason why weight loss outcomes with tirzepatide tend to be higher in clinical trials.

These medications were originally developed for type 2 diabetes management. Weight loss was initially seen as a side effect, but the effect was significant enough that some of these medications are now also approved for obesity management.

The Weight Loss Results Are Significant

The weight loss results with GLP-1 medications are real.

Lifestyle interventions alone often lead to modest weight loss, commonly in the range of 3 to 8 percent of total body weight depending on the level of support and intensity. Clinical trials with GLP-1 medications show much larger reductions.

Semaglutide has been shown to produce roughly 15 percent total body weight loss in some trials. Tirzepatide has shown even higher results, with some studies reporting average losses above 20 percent in people without type 2 diabetes.

These medications can also improve important health markers. Research has shown improvements in blood sugar control, blood pressure, cholesterol, triglycerides, and cardiovascular risk markers, especially in people with obesity-related health conditions.

That matters.

For some people, these medications can be life-changing. They may improve mobility, reduce health risks, and create a sense of control after years of struggling with weight management.

But weight loss alone does not automatically mean better health. What you lose matters.

That brings us to the part that needs far more attention.

The Part That Matters for Training: Muscle Loss

This is the part I care about most as a kinesiologist.

GLP-1 medications can help people lose a significant amount of weight, but the weight lost is not just body fat. Some of it is lean mass, which includes muscle.

That matters because muscle is not just about looking strong. Muscle supports your metabolism, strength, balance, independence, injury resilience, and long-term health.

Body composition research has shown that a meaningful portion of weight lost on GLP-1 medications can come from lean mass. With semaglutide, some research has found that approximately 38 percent of the weight lost came from lean mass. With tirzepatide, the proportion appears lower, closer to 25 percent in some studies, but it is still significant.

This does not mean these medications are bad. It means the way you use them matters.

If someone loses a large amount of weight but also loses a significant amount of muscle, that is not an ideal outcome. The goal should not simply be a lower number on the scale. The goal should be improved body composition, better health, greater strength, and better long-term function.

This is why strength training is not optional if you are using a GLP-1 medication.

Resistance training helps preserve muscle during weight loss. It gives your body a reason to hold onto lean tissue while body weight is coming down. Without it, you are increasing the risk that more of your weight loss comes from muscle.

At a minimum, people using these medications should be strength training 2 to 3 days per week, with a full-body approach that includes major movement patterns like squatting, hinging, pushing, pulling, carrying, and single-leg work.

Cardiovascular training still matters too. These medications can reduce appetite and body weight, but they do not build cardiovascular fitness. Your heart, lungs, and muscles still need training.

The big takeaway is this:

GLP-1 medications may help with weight loss, but exercise determines a lot of what kind of weight you lose, how well you function, and how prepared you are to maintain your results long term.

What Happens If You Stop?

This is another part of the conversation that needs to be discussed before someone starts.

For many people, the weight loss achieved with GLP-1 medications is not fully maintained after stopping the medication.

Clinical trial data shows that weight regain is common after discontinuation. In the STEP 1 extension study, participants regained approximately two thirds of the weight they had lost within one year of stopping semaglutide (Wilding et al., 2022). In the STEP 4 trial, people who stopped semaglutide regained weight, while those who continued treatment lost more weight (Rubino et al., 2021). Similar findings have been reported with tirzepatide, where stopping treatment led to significant regain compared with continued use (Aronne et al., 2024).

This does not mean these medications do not work. It means they appear to work more like long-term treatment for a chronic condition, rather than a short-term fix.

That is an important distinction.

Many people start these medications thinking they will use them temporarily, lose the weight, and then stop. But if stopping leads to significant weight regain, then the long-term plan needs to be part of the conversation from the beginning.

Before starting, it is worth asking:

• Can I afford this long term?

• Am I prepared to stay on it if that is what is needed?

• What happens if side effects become difficult?

• What happens if my coverage changes?

• What habits am I building while I am on it?

• Am I strength training and eating enough protein to protect my muscle?

These are not small questions. They are central to making an informed decision.

Side Effects, Safety, and Medical Supervision

The most common side effects of GLP-1 medications are gastrointestinal. Nausea, diarrhea, constipation, bloating, abdominal discomfort, and indigestion are all commonly reported, especially when starting the medication or increasing the dose.

For some people, these symptoms improve over time. For others, they are significant enough to stop treatment.

There are also less common but more serious risks that need medical oversight, including pancreatitis, gallbladder disease, changes in heart rate, and specific considerations for people with diabetes-related eye disease. These risks do not mean everyone should avoid these medications, but they do mean medical supervision matters.

This is also why the rise in black market and unregulated versions of these medications is concerning.

Because of cost, access issues, and high demand, some people are obtaining compounded, counterfeit, or research versions of these drugs online or outside proper medical channels. That comes with real risk. You may not know the dose, purity, concentration, or safety of what you are taking. You also lose the medical monitoring that should come with these medications.

If you are going to use a GLP-1 medication, use it under the care of a qualified healthcare provider who knows your health history.

What You Should Do If You Are Taking a GLP-1 Medication

If you are currently taking one of these medications, or you are thinking about starting, here are the main things I would want you to prioritize.

First, strength train consistently. Aim for 2 to 3 full-body sessions per week. This is one of the most important things you can do to help preserve muscle while losing weight.

Second, eat enough protein. Appetite suppression can make it harder to eat enough total food, but protein matters for muscle retention, recovery, and long-term health.

Third, do not ignore cardiovascular fitness. Walking, cycling, incline treadmill work, rowing, and other forms of aerobic exercise still matter. These medications do not replace the benefits of conditioning.

Fourth, pay attention to how you feel. Low energy, dizziness, poor recovery, rapid strength loss, and extreme food restriction are not signs that things are going well. They are signs that your plan may need adjusting.

Finally, think beyond the scale. Weight loss can be valuable, but strength, energy, mobility, confidence, and long-term function matter too.

The Bottom Line

GLP-1 medications are powerful tools. The weight loss results are real, and the health benefits can be meaningful, especially for people with obesity-related health conditions.

But they are not a replacement for lifestyle.

They do not build muscle. They do not improve your strength. They do not train your cardiovascular system. They do not address every behavioural, emotional, or environmental factor that may have contributed to weight gain in the first place.

They can be part of the solution, but they should not be the whole solution.

If you are using a GLP-1 medication, strength training should be a priority. So should protein, movement, sleep, and a realistic long-term plan.

The goal is not just to lose weight.

The goal is to lose weight in a way that protects your muscle, supports your health, and helps you function better for years to come.

This post is intended for general educational purposes only and is not medical advice. Always speak with a qualified healthcare provider before starting, changing, or stopping any medication.

References

Aronne, L. J., et al. (2024). Continued treatment with tirzepatide for maintenance of weight reduction in adults with obesity: The SURMOUNT-4 randomized clinical trial. JAMA, 331(1), 38-48.

Kolli, R. T., Aoutla, S., Jyothi, N., et al. (2025). Rebound or retention: A meta-analysis of weight regain after the discontinuation of glucagon-like peptide-1 receptor agonists and other anti-obesity drugs. Cureus, 17(10), e94926.

Moiz, A., Filion, K. B., Knäuper, B., et al. (2026). Weight maintenance after discontinuation of GLP-1 therapies. eClinicalMedicine, 96, 103992.

Rubino, D., et al. (2021). Effect of continued weekly subcutaneous semaglutide vs placebo on weight loss maintenance in adults with overweight or obesity: The STEP 4 randomized clinical trial. JAMA, 325(14), 1414-1425.

Wilding, J. P. H., et al. (2022). Weight regain and cardiometabolic effects after withdrawal of semaglutide: The STEP 1 trial extension. Diabetes, Obesity and Metabolism, 24(8), 1553-1564.

Diabetes Care. (2025). Standards of care in diabetes. Diabetes Care, 49(Suppl. 1), S89-S131.

Endocrine Practice. (2025). Clinical practice guidance related to obesity and incretin-based therapies. Endocrine Practice, 31(11), 1351-1394.

Metabolism. (2025). Lean mass changes during GLP-1 based therapy. Metabolism, 164, 156113.

Diabetes, Obesity and Metabolism. (2025). Tirzepatide trial data and cardiometabolic outcomes. Diabetes, Obesity and Metabolism, 27(10), 5386-5392.

BMJ. (2025). Warning regarding unregulated GLP-1 products. BMJ, 390, r1917.

Health Canada. (2026). Public advisory on unauthorized GLP-1 products.

Therapeutic Goods Administration. (2026). Safety alert regarding counterfeit GLP-1 products.

What Is the Stack? How Rib Cage and Pelvis Position Affect Movement

Written by Evelyn Calado, MKin, CSCS, RKin

If you've trained at Avos Strength for any length of time, you've probably heard us talk about "the stack."

Whether we're coaching a squat, a deadlift, a breathing drill, a carry, or simply standing posture, the concept comes up repeatedly.

That's because the stack is one of the foundational principles that influences how we breathe, move, stabilize, and produce force.

While it may seem like a small detail, it often has a significant impact on movement quality and performance.

What Is the Stack?

At its simplest, the stack refers to the relationship between the rib cage and the pelvis.

One way to visualize this is to think of both the rib cage and pelvis as buckets of water. When the buckets are stacked on top of one another and remain relatively level, the body is generally in a better position to manage pressure, breathe efficiently, and move well.

When either bucket tips excessively forward or backward, the relationship between the rib cage and pelvis changes. The body may then rely on compensatory strategies to create stability, manage pressure, or access movement.

While no one maintains a perfectly stacked position all the time, this analogy provides a useful framework for understanding why rib cage and pelvic position matter.

When we talk about being stacked, we're generally referring to the rib cage being positioned over the pelvis.

This doesn't mean flattening the spine, tucking the pelvis excessively, or walking around with your ribs permanently pulled down.

A stacked position still maintains the natural curves of the spine. Instead, it creates an environment where the body can effectively manage pressure, breathe efficiently, and move through available ranges of motion.

From a biomechanical perspective, stacking helps align the thoracic diaphragm and the pelvic floor. These structures form the top and bottom of a pressure system that works together with the abdominal wall to create stability throughout the trunk.

When the rib cage and pelvis are positioned well relative to one another, the body has a stronger foundation from which movement can occur.

Why We Coach the Stack

Many people think of strength, mobility, and stability as separate qualities.

In reality, they are deeply connected.

One of the primary reasons we coach the stack is because it influences the body's ability to manage pressure.

The diaphragm sits at the top of the abdominal cavity. The pelvic floor sits at the bottom. The internal obliques, transverse abdominis, and other abdominal muscles form the walls of this cylinder.

Together, these structures help regulate intra-abdominal pressure.

This pressure system plays a critical role in spinal stability, force transfer, breathing mechanics, and movement efficiency.

When pressure is managed effectively, the body is often able to access movement options more easily and distribute forces more efficiently.

A useful way to think about this is to imagine an empty aluminum pop can. Despite being made of very thin metal, an undamaged can can support a surprising amount of weight when force is distributed evenly through the structure. The moment the side of the can is dented, however, its ability to manage force drops dramatically.

While the human body is far more complex than a pop can, the analogy illustrates an important principle. When the diaphragm, abdominal wall, pelvic floor, rib cage, and pelvis work together to manage pressure, the trunk becomes remarkably efficient at transferring and resisting force.

When pressure management is compromised, the body may begin relying on compensatory strategies to create stability and movement.

The stack is not the solution to every problem, but it often provides the foundation that allows other solutions to work.

How the Stack Affects Breathing

Breathing is much more than simply getting air into the lungs.

Effective breathing requires coordination between the diaphragm, rib cage, abdominal wall, and pelvic floor. Together, these structures help create and manage pressure throughout the trunk, providing a foundation for both movement and stability.

When the rib cage and pelvis are positioned well relative to one another, the diaphragm is able to function more effectively. One reason for this is a concept known as the Zone of Apposition, which refers to the area where the diaphragm sits against the inner surface of the lower rib cage.

While the details are beyond the scope of this article, the important takeaway is that the position of the rib cage influences the position and function of the diaphragm.

When the rib cage becomes excessively elevated or flared, the diaphragm may lose some of its mechanical advantage. As a result, the body often begins relying more heavily on accessory muscles of respiration, including muscles of the neck, upper chest, and lower back.

This is one reason why individuals who struggle with breathing mechanics frequently report chronic tension through the neck, shoulders, or low back.

A complete exhalation is often one of the simplest ways to improve this relationship. Exhaling fully helps bring the rib cage down and in, allowing the diaphragm to return to a more advantageous position and creating a better starting point for the next inhale.

When the stack is present, we should see expansion occur throughout the rib cage and abdominal canister rather than exclusively through the chest, shoulders, neck, or belly.

This includes expansion through the front, sides, and back of the rib cage, as well as coordinated movement of the diaphragm and pelvic floor. This is often referred to as 360-degree expansion.

The rib cage itself is designed to move in multiple directions during respiration. As we inhale, the ribs expand and rotate to accommodate incoming air. As we exhale, they return toward a more neutral position. These movements help distribute pressure throughout the system and allow breathing to support movement rather than interfere with it.

When the stack is lost, these expansion patterns can become biased toward a particular region. Some individuals become upper-chest dominant, relying heavily on the neck and shoulders to breathe. Others primarily expand through the front of the abdomen while gaining little expansion through the sides and back of the rib cage.

Our goal is not simply to breathe into the chest or the belly. Our goal is to create balanced expansion throughout the entire canister, allowing the body to efficiently manage pressure, move well, and perform at its best.

How the Stack Affects Mobility

One of the most common misconceptions in fitness is that mobility limitations are always the result of tight muscles.

While tissue restrictions can certainly exist, many mobility limitations are influenced by joint positioning and pressure management.

The body is often reluctant to access movement that it cannot control.

When the rib cage and pelvis are poorly positioned relative to one another, the body may lose access to certain movement options.

This can influence hip internal rotation, thoracic rotation, shoulder motion, and other ranges of motion throughout the body.

As a result, an individual may feel stiff or restricted despite spending significant amounts of time stretching.

In some cases, restoring a better stack can immediately improve movement quality without any traditional stretching at all.

This doesn't mean stretching is unnecessary. Rather, it highlights the importance of addressing the underlying positional and pressure-management strategies that influence movement.

At Avos Strength, we frequently assess movement both before and after breathing and positional interventions. It is not uncommon to see meaningful changes in mobility once the body is placed in a position that allows it to better manage pressure.

How the Stack Affects Strength and Performance

Strength is ultimately the ability to produce and transfer force.

The stack plays an important role in both.

When the rib cage and pelvis are positioned effectively, the body is often better able to transfer force between the upper and lower extremities.

This can influence performance in squatting, deadlifting, pressing, carrying, sprinting, jumping, and change-of-direction activities.

The stack also influences the body's center of mass.

An individual's ability to shift, rotate, accelerate, and decelerate depends in part on where their mass is positioned and how effectively they can manage it.

When the body relies heavily on compensatory strategies, force production may become less efficient and movement options may become more limited.

This is one reason why we frequently revisit the stack during both rehabilitation and performance-focused training.

How We Help Clients Find Their Stack

For most clients, learning the stack begins with breathing.

One of the simplest ways to improve the relationship between the rib cage and pelvis is through a full exhalation. By fully exhaling, the ribs are able to move down and in, allowing the diaphragm, abdominal wall, and pelvic floor to work together more effectively.

If you'd like to try this yourself, watch our short video demonstrating how to find a stacked position from standing.

For some individuals, finding this position can be challenging while standing. In these situations, positional drills may be useful. Exercises such as a 90-90 Hip Lift can help reduce the influence of gravity and provide the body with a simpler environment in which to learn how to manage pressure and find a stacked position.

From there, we gradually integrate these concepts into movement.

This may involve developing awareness of rib cage position, pelvic position, foot pressure, breathing mechanics, and how these factors influence movement quality.

The appropriate strategy depends on the individual.

Our goal is not to force every client into the same posture. Rather, we aim to improve their ability to manage pressure, access movement options, and move efficiently.

As clients become more aware of these relationships, they often develop a greater understanding of how breathing, mobility, strength, and movement quality are interconnected.

Final Thoughts

The stack is not a magic position.

Nor is it a position that we aim to maintain at all times.

Movement is dynamic. Athletes constantly move through flexion, extension, rotation, and lateral movement depending on the demands of the task in front of them. The goal is not to remain perfectly stacked at all times or to create a rigid posture. Rather, the stack provides a foundation from which movement can occur. When the body can effectively organize the relationship between the rib cage and pelvis, it is often better able to transition into and out of different positions while maintaining efficient breathing, pressure management, and force production.

The stack simply provides a foundation.

It is a position from which the body can effectively manage pressure, breathe efficiently, and access movement options when needed.

When the rib cage and pelvis work together effectively, the body is often able to breathe better, manage pressure more efficiently, access movement options, and transfer force more effectively.

For that reason, the stack remains one of the most important concepts we teach at Avos Strength.

Whether the goal is improved mobility, greater strength, athletic performance, or simply moving and feeling better, the stack provides a foundation upon which all of those qualities can be built.

How Tongue Position and Jaw Function May Improve Strength, Balance, and Breathing

Part 1 of the Improving Force Production and Movement From Head to Toe Series

Written by Michael Crawley, BSc, BPT, CSCS

Introduction

When people think about improving strength and force production, attention is usually directed toward the obvious areas: the legs, hips, trunk, and shoulders. Rarely does anyone consider the tongue or jaw.

At first glance, this seems reasonable. The tongue is typically associated with speech, swallowing, and airway function rather than athletic performance. However, emerging research suggests that tongue position, tongue strength, and jaw function may influence force production, balance, coordination, and respiratory mechanics.

Force is rarely generated by a single muscle or body part in isolation. Instead, it is transferred throughout the body as multiple regions work together. A foundational piece of this is learning how to position the body to generate and transmit tension effectively. As covered in The Stack blog post, the alignment of the rib cage relative to the pelvis and head provides a structural template that underpins efficient force production. The strategies explored in this series build on that foundation.

This article is the first in a series examining how different regions of the body contribute to force production and movement quality. We will begin at the top, exploring the tongue and jaw, before working downward through the diaphragm and foot.

Series Breakdown

This series will explore three often-overlooked contributors to force production, movement quality, and long-term function:

1. The tongue and jaw

2. The diaphragm and bracing

3. The foot and pressure distribution

Together, these concepts provide additional tools that may help an individual break through a plateau in a lift, improve their strategies to strength train, or attenuate some of the deficits and systemic problems which develop with age. Each of these builds on the positional foundation established in The Stack.

The Tongue & Jaw: Pressure and Position

The embryological development and anatomy of the tongue can shed light on how it is a forgotten piece in strength training and human function beyond mastication and speech. The tongue consists of intrinsic and extrinsic muscle connections. This allows an intricate dance where the complex can adapt its activation and position differently during breathing and swallowing (Fregosi and Ludlow 2014).

The tongue has the same neural origins as the hyoid bone and associated musculature involved in head and neck stabilization. The hyoid bone is a floating bone acting as an interface for the origin of the tongue and connector of important neck and jaw muscles.

There is a functional relationship between the tongue and diaphragm, demonstrated through the coordinated activation of specific extrinsic tongue muscles during respiration (Sokoloff 2004). As a result, tongue function can influence how easily air moves through the airway and how efficiently we breathe. This will really be hammered home in Part 2 regarding the diaphragm and bracing.

The tongue and jaw do not operate independently. Resting tongue position helps influence both jaw alignment and head posture, with the ideal resting position being the tongue gently placed against the roof of the mouth.

The jaw is also closely connected to the neck and upper body through muscles, nerves, and connective tissues (Silveira et al. 2015). Because of these connections, changes in jaw position can influence how the head, neck, and shoulders work together.

This is important because force is rarely generated by a single muscle or body part. Instead, it is transferred throughout the body as multiple regions work together. The tongue and jaw may seem far removed from exercises such as squats, deadlifts, or carries, but their connections to the neck and upper body suggest they can still influence posture, stability, and force production.

The image below highlights some of the tissues that link the jaw, neck, and shoulder region. Next, we will discuss how tongue function changes over time and why this may be particularly important for the older athlete.

Importance of Tongue Function in the Older Athlete

When most people think about age-related muscle loss, they think of weaker legs, reduced grip strength, or difficulty getting up from a chair. What is often overlooked is that the tongue also loses strength and muscle mass with age.

This decline in tongue function has been associated with several important health concerns, including impaired swallowing, increased risk of aspiration, and poorer balance (Bordoni et al. 2018). In other words, tongue function may influence much more than speech or eating.

For older athletes and gym-goers, this creates an interesting opportunity. Maintaining tongue strength and awareness may be a simple strategy to support both performance and long-term health. While it is unlikely to be the most important piece of the puzzle, it may be one of the easier ones to address. Similar to strength training itself, small improvements maintained over time can have a meaningful impact on long-term health, balance, and independence.

This could be as simple as applying firm tongue pressure to the roof of the mouth during heavier lifts or practicing proper resting tongue position while performing breathing exercises and warm-up activities.

Evidence of Tongue Pressure and Strength Performance

At this point, it is reasonable to ask whether tongue position and tongue pressure actually influence strength and movement, or whether this is simply an interesting anatomical discussion.

While the research in this area is still developing, several studies have demonstrated improvements in force production, balance, and movement performance when tongue position or tongue stimulation is altered.

Some examples include:

• Saito et al. (2022) demonstrated that the rate of force development (RFD) of tongue pressure was strongly correlated with knee extensor strength and single-leg stand time in adults over 65.

• di Vico et al. (2013) found that tongue position significantly impacted knee flexor strength test performance. Participants generated approximately 30% greater force when the tongue was pressed against the roof of the mouth compared to a resting position.

• Wildenberg et al. (2010) found improvements in balance and postural sway following external tongue stimulation in older adults.

Taken together, these findings suggest that tongue function may influence more than just speech, swallowing, and breathing. It may also play a role in force production, balance, and coordination.

This does not mean tongue position should become the primary focus of a training program. Rather, it may represent another small but useful strategy that can be incorporated alongside sound strength training principles.

The diagram below demonstrates the recommended tongue position, with the tongue resting against the roof of the mouth and the tip sitting just behind the upper front teeth. The next question is why these changes might influence performance in the first place.

Why Might the Tongue and Jaw Influence Performance?

At this point, the obvious question is: why would tongue position or jaw activity affect strength, balance, and movement quality in the first place?

The honest answer is that we do not know exactly. While the relationship between tongue position and breathing is well established, the mechanisms behind its apparent influence on force production and coordination are still being investigated.

Several theories have been proposed, including changes in nervous system activation, interactions between cranial nerves involved in coordination, and connective tissue links between the tongue, neck, and chest (Bordoni et al. 2018). Regardless of the exact mechanism, multiple studies have demonstrated improvements in strength, balance, and movement performance when tongue position, tongue pressure, or jaw activity are altered.

Similar findings have been reported with jaw clenching. Research has demonstrated improvements in force production, grip strength, jumping performance, rowing strength, and balance when a jaw clench is incorporated during testing (Allen et al. 2017; Buscà et al. 2016; Alghadir et al. 2015).

However, there is an important trade-off. Unlike tongue position, excessive or habitual jaw clenching can contribute to issues such as teeth grinding (bruxism) and temporomandibular joint (TMJ) irritation. For that reason, I generally place greater emphasis on tongue position and tongue strength than aggressive jaw clenching. The potential benefits appear similar, while the downside risk is lower.

The broader lesson is that force production is not simply a function of the muscles directly involved in a lift. The body operates as an integrated system, and seemingly small factors such as tongue position, breathing strategy, and jaw position may influence how force is generated and transferred throughout the body.

This is one reason why movement assessments should look beyond individual muscles and joints. At Avos Strength, our assessment process examines how multiple systems work together to influence movement quality, performance, and long-term function.

Summary

The tongue and jaw may influence more than speech, swallowing, and chewing. Research suggests they can also affect breathing, balance, coordination, and force production.

While these factors are unlikely to be the primary drivers of performance, they represent simple strategies that may improve movement quality and strength expression when combined with sound training principles.

For older adults, maintaining tongue function may also have benefits beyond the gym, supporting balance, respiratory function, and overall quality of life.

Takeaways

• Pressing the tongue firmly against the roof of the mouth may help improve force production during strength exercises.

• Resting the tongue gently against the roof of the mouth can support an open airway and efficient breathing during mobility, warm-up, and recovery work.

• Jaw clenching may improve strength, jumping performance, and balance, but excessive or habitual clenching can contribute to jaw irritation and teeth grinding.

• If choosing between the two strategies, tongue position is likely the lower-risk and more practical place to start.

• These concepts should be viewed as small pieces of the puzzle, not replacements for sound strength training, recovery, and exercise technique.

Next Up

In Part 2, we will move one step lower and examine the diaphragm, breathing, and bracing.

Topics will include:

• Basic diaphragm anatomy and function

• The relationship between breathing and trunk stability

• Bracing strategies for strength training performance

• Practical applications for both performance and long-term health

References

Alghadir, A. H. et al. 2015. Effect of three different jaw positions on postural stability during standing. Funct Neurol 30(1), pp. 53-57.

Allen, C. et al. 2017. The Effects Of Jaw Clenching And Jaw Alignment Mouthpiece Use On Force Production During Vertical Jump And Isometric Clean Pull. Journal of Strength and Conditioning Research 32, p. 1. doi: 10.1519/JSC.0000000000002172

Bordoni, B. et al. 2018. The Anatomical Relationships of the Tongue with the Body System. Cureus 10. doi: 10.7759/cureus.3695

Buscà, B. et al. 2016. Effects of Jaw Clenching While Wearing a Customized Bite-Aligning Mouthpiece on Strength in Healthy Young Men. The Journal of Strength & Conditioning Research 30(4).

di Vico, R. et al. 2013. The acute effect of the tongue position in the mouth on knee isokinetic test performance: a highly surprising pilot study. Muscles Ligaments Tendons J 3(4), pp. 318-323.

Fregosi, R. F. and Ludlow, C. L. 2014. Activation of upper airway muscles during breathing and swallowing. J Appl Physiol 116(3), pp. 291-301. doi: 10.1152/japplphysiol.00670.2013

Miró, A. et al. 2023. Acute effects of jaw clenching while wearing a customized bite-aligning mouthguard on muscle activity and force production during maximal upper body isometric strength. Journal of Exercise Science & Fitness 21(1), pp. 157-164. doi: https://doi.org/10.1016/j.jesf.2022.12.004

Saito, S. et al. 2022. Relationship between Rate of Force Development of Tongue Pressure and Physical Performance. J Clin Med 11(9). doi: 10.3390/jcm11092347

Silveira, A. et al. 2015. Jaw dysfunction is associated with neck disability and muscle tenderness in subjects with and without chronic temporomandibular disorders. Biomed Res Int 2015, p. 512792. doi: 10.1155/2015/512792

Sokoloff, A. J. 2004. Activity of tongue muscles during respiration: it takes a village? Journal of Applied Physiology 96(2), pp. 438-439. doi: 10.1152/japplphysiol.01079.2003

Wildenberg, J. C. et al. 2010. Sustained cortical and subcortical neuromodulation induced by electrical tongue stimulation. Brain Imaging Behav 4(3-4), pp. 199-211. doi: 10.1007/s11682-010-9099-7

Why Your Training Program Won’t Work Without Sleep, Nutrition, and Recovery

Written by Evelyn Calado, MKin, CSCS, RKin

One of the hardest things for coaches to accept is this:

You can write the most detailed, individualized, evidence-informed training program possible, and it still may not work if the big rocks are not in place.

I’ve seen this over and over again throughout my coaching career.

The athlete is committed.
They show up consistently.
They follow the sets, reps, tempos, and rest periods.
They train hard.
They genuinely want results.

But outside the gym?

They’re sleeping five hours a night.
Their stress is through the roof.
They barely drink water.
Their nutrition is inconsistent.
They rely on caffeine to survive the day and supplements to try to “fix” the problem.

At some point, the body stops being able to recover.

And recovery is where adaptation actually happens.

You Don’t Get Better During Training

Training is the stimulus.

Recovery is where the body adapts.

That means if you’re constantly exhausted, under-fueled, dehydrated, stressed, or running on poor sleep, your body has a much harder time repairing tissue, building muscle, improving conditioning, regulating hormones, and recovering from the demands of training.

This is one of the reasons why two people can follow the exact same program and get completely different results.

The program matters.

But the foundation matters more.

This is also why progress in strength, muscle growth, and conditioning often takes longer than people expect. Adaptation requires recovery capacity. How Long Does It Take to See Results from Training

Sleep Is One of the Biggest Performance Enhancers We Have

This is probably the most common issue I see.

People want better energy, better recovery, improved body composition, more muscle mass, lower pain levels, and better athletic performance, but they’re sleeping poorly every single night.

If you constantly wake up throughout the night, struggle with insomnia, or spend most of your day exhausted, your recovery capacity drops significantly.

Sleep impacts:

• Recovery from training

• Muscle repair and growth

• Hormonal regulation

• Mood and mental health

• Pain sensitivity

• Cognitive function

• Energy levels

• Immune function

You cannot out-train chronic poor sleep.

And no supplement stack is going to replace it.

Recovery Is More Than Just Taking a Rest Day

A lot of people think recovery simply means taking a day off from training.

But recovery is much bigger than that.

Recovery includes:

• Sleep quality

• Nutrition

• Hydration

• Stress management

• Recovery between training sessions

• Nervous system regulation

• Overall lifestyle habits

You cannot continuously add more stress to the system without giving the body the resources it needs to recover and adapt.

Sometimes the issue is not the program itself.

Sometimes the body simply has no remaining capacity to tolerate additional stress.

Stress Is Still Stress

This is another major piece people underestimate.

Your body does not separate “life stress” from “training stress.”

Heavy training is a stressor.
Long work hours are a stressor.
Financial pressure is a stressor.
Relationship issues are a stressor.
Anxiety is a stressor.

It all contributes to your total stress load.

One book I often recommend is the Why Zebras Don't Get Ulcers by Robert Sapolsky, which discusses how humans often stay stuck in a chronic fight-or-flight state.

A lot of people are constantly “on.”

Their nervous system never really gets a chance to downshift.

Then they wonder why they feel exhausted, inflamed, sore, unmotivated, or unable to recover.

Nutrition Is Not Optional

You cannot build a high-performing body without giving it the raw materials it needs.

Protein matters.
Micronutrients matter.
Overall calorie intake matters.
Hydration matters.

If most of your diet consists of highly processed foods, takeout, chips, candy, and energy drinks, your recovery, energy levels, body composition, and performance are going to suffer.

That does not mean you need to eat “perfectly.”

But your body still needs adequate nutrients and amino acids to:

• Build and maintain muscle

• Recover from training

• Support connective tissue health

• Improve body composition

• Regulate energy levels

• Support overall health and longevity

Supplements can support a good foundation.

They cannot replace one.

Creatine is great.
Protein powder can be helpful.
Certain supplements absolutely have value.

But supplements cannot compensate for chronic sleep deprivation, poor nutrition, dehydration, and unmanaged stress.

If you want a deeper breakdown on the supplements that actually matter most for recovery and performance, check out The Only Two Supplements Most Athletes Actually Need.

Hydration Is More Important Than People Think

This is another one that gets overlooked constantly.

The number of people I meet who drink one or two glasses of water per day is honestly surprising.

Many people function almost entirely on coffee and caffeine.

Hydration impacts:

• Performance

• Recovery

• Energy

• Cognition

• Joint comfort

• Muscle function

• Cardiovascular function

Even mild dehydration can negatively affect how you feel and perform.

Coaches Cannot Do The Work For You

As coaches, we can guide you.
We can educate you.
We can build individualized programs.
We can adjust your training loads.
We can help create structure and accountability.

But we cannot sleep for you.
We cannot manage your stress for you.
We cannot hydrate for you.
We cannot make your nutritional choices for you.

If we see you twice per week in person, that’s two hours out of a 168-hour week.

The other 166 hours matter.

A lot.

This is one of the reasons why our initial assessment process focuses on more than just exercises and sets and reps. Understanding lifestyle, recovery, stress, injury history, and daily habits matters when building an individualized plan. What Actually Happens During an Initial Assessment?

The Big Rocks Come First

People often search for advanced solutions before they’ve mastered the fundamentals.

They want the perfect program.
The perfect supplement stack.
The perfect recovery gadget.
The perfect optimization strategy.

Meanwhile:

• They sleep poorly

• They are chronically stressed

• They barely eat protein

• They drink almost no water

• They recover inconsistently

The basics are not boring.

The basics are foundational.

And honestly, these “big rocks” are not just important for performance or body composition goals. They are fundamental for living a healthier, more energetic, and more resilient life.

That’s one of the reasons why strength training and recovery habits become increasingly important as we age. Strength Training for Longevity: Staying Active, Capable and Competitive as You Age

Training matters.
Strength matters.
Conditioning matters.

But none of it works as well if the foundation underneath it is unstable.

Get the big rocks in place first.

Everything else works better after that.

At Avos Strength, we focus on individualized coaching that takes into account your training history, recovery capacity, lifestyle, stress levels, and long-term goals. Training is important, but sustainable progress comes from addressing the full picture.

If you’re looking for guidance with strength training, recovery, performance, or long-term health, you can learn more about our coaching and assessment services here.

Frozen Shoulder: Unravelling the Complexities and Providing Clarity

Written by Michael Crawley, BSc, BPT, CSCS

Nearly 100 years ago, Earnest Codman coined the term “frozen shoulder” and highlighted three clinical issues (Salamh et al. 2025):

• Difficult to define

• Difficult to treat

• Difficult pathology to explain to patients

Those three points still hold true today.

Multiple structures and pathological findings have been implicated in the development of frozen shoulder. This includes the accumulation of immune system mediators, thickening of ligaments, and altered collagen translation (Pandey and Madi 2021). Clinically, this presents as a shoulder with reduced range of motion in both active and passive flexion, abduction, and external rotation (as seen in the image below).

Figure 1: Reduced Shoulder range of motion (ROM) with frozen shoulder

The Real Impact of Frozen Shoulder

A scoping review examining how people experience and live with frozen shoulder demonstrates how debilitating and impactful the condition can be. King and Hebron (2023) identified five major themes:

1. “Dropping me to my knees, due to the pain”

2. Struggle for normality

3. Emotional change for self

4. Challenges through the healthcare journey

5. Coping & adapting

This highlights that frozen shoulder is not just a physical limitation. It can significantly alter how someone functions and experiences their daily life.

Unfortunately, frozen shoulder demonstrates a bias towards a particular demographic. Females in the 40–60 age category take the brunt of diagnoses. To rub salt in the wounds, females are more likely to experience a more prolonged and symptomatic course compared to male counterparts.

Types of Frozen Shoulder

Frozen shoulder can be broadly classified into two categories (Pandey and Madi 2021):

Primary:
A stiff shoulder developing with no known cause. However, there are commonly linked conditions, most notably diabetes mellitus and thyroid dysfunction. The incidence of frozen shoulder can reach as high as 30% in individuals with diabetes.

Secondary:
A stiff shoulder with an underlying cause such as direct trauma (e.g. a fall), infection, or inflammatory conditions.

The Three Stages of Frozen Shoulder

Frozen shoulder follows a series of stages, delineated by changing symptoms (Date and Rahman 2020). While approximate timelines are often attached, there is significant variability, and for some individuals, full resolution may not occur within 3–5 years.

Freezing Stage (Stage 1: 2–6 months)

• Predominantly characterised by moderate to severe pain and partial restriction of ROM

• Early stages may present with pain and only terminal loss of ROM

This stage can be confused with rotator cuff tendinopathy. However, ROM does not progressively worsen in tendinopathy, whereas it continues to worsen with each follow-up in frozen shoulder.

Frozen Stage (Stage 2: 4–12 months)

• Characterised by both pain and stiffness in varying proportions

• Early phase tends to be more pain-dominant

• Later phase becomes more stiffness-dominant

Thawing Stage (Stage 3: 6–26 months)

• Characterised by minimal pain

• Gradual resolution of stiffness

• Progressive return of movement

Pathologically, this reflects a gradual reduction in inflammation and restoration of movement.

Treatment and Management Across the Stages

What actually works, and when it matters

The research on the effectiveness of treatments for frozen shoulder remains conflicting. However, a conservative approach is typically recommended as the starting point (Date and Rahman 2020).

Common interventions include:

• Analgesics

• Physiotherapy

• Intra-articular injections

• Suprascapular nerve block

Early Stage: Movement Within Tolerance

In the early stage of frozen shoulder, gentle stretching and mobility exercises within a pain-free range are advised (Date and Rahman 2020).

Creativity can play a key role here, as Louis Gifford, the brilliant pain specialist, stresses. In his book Aches and Pains, he explains how adjusting body position can influence the amount of pain-free range available to a limb.

The videos below demonstrates this concept. The key idea is simple:

• The arm can move relative to the body

• Or the arm can stay fixed while the body moves around it

Shoulder Range of Motion Wall Drills:
https://youtu.be/9_GwO7r24hM

Passive and active-assisted exercises can also be incorporated. These reduce the working stress on affected structures, allowing the humerus to move through range without generating or exacerbating pain.

Active Assisted and Passive Shoulder:
https://youtu.be/072jZDVW-ac

As Pain Settles: Introducing Strength

As pain begins to reduce and become more manageable, strengthening exercises can be introduced.

Here, the principle that “the dose and position make the poison” becomes particularly relevant.

Using isometrics in varying positions and directions allows for global loading through the shoulder while staying within tolerable limits.

Entry Level Isometric:
https://youtu.be/mDzgyyKlzZo

Later Stages: What Are Mobilisations Actually Doing?

Mobilisations performed by a physiotherapist in the later stages have shown some utility. However, the mechanism behind their effectiveness is contested.

For many years, the prevailing thought was that inferior mobilisation directly impacted the shoulder joint capsule. However, Jeremy Lewis, a well-known Australian shoulder specialist, has pointed out that a physiotherapist would need to generate approximately 600kg of force to meaningfully affect the capsule.

I am not aware of many Canadians with a 600kg deadlift.

The best approach at this stage would be to continue to progress strength training through pain free range.

Injections and Medical Management: Timing Is Key

Outside of physiotherapy, injections and pharmacological treatments are often used.

Nonsteroidal anti-inflammatories have shown little impact in the case of frozen shoulder. Intra-articular steroid injections, however, have demonstrated positive effects, particularly when used at the right time.

Again, Jeremy Lewis stresses that these injections must be used in the early stages, when pain is highest. This reinforces the importance of early and accurate diagnosis.

A similar pattern is seen with suprascapular nerve blocks, which can also have a positive effect on pain relief when applied early (Date and Rahman 2020).

Surgical Options: Often Less Helpful Than Expected

Surgical options are available, but often yield little additional benefit.

Beard et al. (2018) found no clinically significant benefit of shoulder arthroscopy compared to sham surgery. This was further supported by the large UK FROST trial (Corbacho et al. 2021), which reported that early physiotherapy was more cost-effective and accessible compared to invasive and costly surgical approaches.

Interestingly, manipulation under anaesthetic, which previously had negative connotations, has shown some efficacy. This likely relates to the reduction of muscle guarding and tension that can develop with frozen shoulder. When under anaesthetic, this guarding effect is temporarily removed.

Looking Beyond the Shoulder

An important point that is often not expressed or evaluated in the research is that frozen shoulder may be a sign of broader health issues, stemming from multiple systems in the body.

In many cases, it can act as a wake-up call to incorporate strength and conditioning into your lifestyle and address other health metrics.

You may not be able to train the affected side in the same way, but there are still many full-body exercises that can be performed without exacerbating the shoulder:

• Towing a sled

• Belt squat

• Walking lunges

• Step-ups

Why This Matters

There are three key reasons why this approach is important:

1. Approximately 1 in 5 people go on to develop similar symptoms in the opposite shoulder (Pandey and Madi 2021)

2. Sedentary individuals are more likely to receive a frozen shoulder diagnosis

3. Well-designed strength and conditioning programs can positively influence the systems linked to frozen shoulder development, including endocrine, immune, and cardiovascular systems

Deeper Dive into Causation and Management

Recent research has continued to highlight the multi-faceted nature of frozen shoulder and the challenges associated with its management (Navarro-Ledesma 2025a).

This is not a condition driven by a single structure or isolated tissue. Instead, it reflects the interaction of multiple systems within the body.

The diagram below highlights this well. Rather than being caused by one specific issue, frozen shoulder appears to sit at the intersection of several physiological systems, all of which can influence one another.

Estrogen and Menopause

One of the more consistent patterns seen in the research is the increased prevalence of frozen shoulder in peri-menopausal women. This has led to estrogen being identified as a key player in its development (Wend et al. 2012).

As shown in figure below, estrogen has effects that extend well beyond the reproductive system. Its influence spans multiple systems that are directly relevant to frozen shoulder.

Neuroendocrine System

Declining estrogen levels can influence the nervous system through several mechanisms, impacting pain thresholds, resilience to stress, and central sensitisation.

A useful way to think about this is the “fire alarm” analogy.

You leave the bacon on the grill too long and the fire alarm goes off because of the smoke. There is no fire, but the system reacts as if there is.

With reduced estrogen levels, the threshold for triggering that “alarm” can become lower. The result is an amplified pain experience, even when the underlying tissue irritation may not fully justify it.

Metabolic System

Estrogen also plays a key role in fat metabolism, glucose regulation, and resistance to oxidative stress.

When these systems are disrupted, it can create an internal environment where tissue repair is compromised. This contributes to fibrosis, which is a hallmark of frozen shoulder.

Immune System

The same pattern continues within the immune system.

Declining estrogen levels tend to promote a more pro-inflammatory state. Immune system mediators accumulate within the tissues involved in frozen shoulder, and when combined with metabolic dysfunction, this can further drive the condition.

Targeting the System, Not Just the Shoulder

The research highlights how frozen shoulder is influenced by multiple systems, not just the shoulder itself. As a result, management is not limited to physiotherapy or surgical intervention alone.

There are a number of factors that could be explored here, but for the purpose of this piece, three of the more relevant and actionable areas will be discussed below.

Strength and Conditioning

Well-designed and properly implemented strength and conditioning programs have demonstrated positive impacts on estrogen levels, muscle mass, and fat mass in menopausal women (Razzak et al. 2019).

As mentioned previously, even with an impacted and painful shoulder, this does not mean avoiding training altogether or waiting for full resolution before doing anything.

The whole-body and multi-system benefits of strength training can influence long-term outcomes indirectly. While the shoulder itself may be limited, the broader physiological adaptations still matter.

Nutrition

Diet quality also plays a meaningful role.

A nutritional approach centred around higher-quality, minimally processed foods has been shown to impact symptom severity in individuals with frozen shoulder (Hamed-Hamed et al. 2026).

In practice, the decision to implement a structured strength training program often leads to improvements in other lifestyle behaviours, including dietary choices.

In the same way that hormonal, metabolic, and immune factors can drive the development of frozen shoulder, lifestyle decisions can push back against these drivers. This not only has the potential to improve current symptoms, but also to reduce the likelihood of future development.

Sleep and Circadian Rhythm

Circadian rhythm and sleep regulate inflammatory processes, hormonal release, and tissue repair (Navarro-Ledesma 2025a).

These are central to both general health and the development and recovery of frozen shoulder, as well as adaptation to strength training and exercise.

This is where the entanglement of systems becomes more apparent.

Bringing It Together

Sleep, exercise, and nutrition can be thought of as a three-legged stool. Each supports the others, and removing one weakens the entire system.

Addressing these factors will not provide an immediate solution to frozen shoulder. However, they can set the conditions for recovery and reduce the likelihood of recurrence, particularly when considering that approximately 20% of individuals will experience similar symptoms in the opposite shoulder.

Summary and Takeaways

Frozen shoulder is a systems issue, not just a joint problem

Frozen shoulder is not a local condition. It can have significant and long-term effects on both physical and psychological well-being.

In some cases, it can be so debilitating that it alters how an individual functions day to day. That may sound hyperbolic, but when revisiting the five themes outlined earlier, alongside the number of systems involved, it becomes more understandable.

Approaching treatment with a reductionist lens, relying solely on an injection or a home exercise program, is akin to using a hammer where a scalpel is required. This sentiment is supported in a recent review by Brindisino et al. (2026).

Effective management requires a more nuanced and personalised approach that considers the multiple drivers involved:

• Hormonal (endocrine)

• Immune system (autoimmune / inflammatory)

• Strength, mobility, and capacity

• Cardiovascular health

• Pain psychology (sensitisation and emotional drivers)

• Structural factors

• Circadian rhythm and sleep

Key Takeaways

• General strength training can still be completed and is beneficial with a frozen shoulder diagnosis

• Surgical interventions are often unwarranted and do not demonstrate superior outcomes

• Frozen shoulder is multi-factorial, and lifestyle factors such as exercise, nutrition, and sleep play a critical role in both management and risk reduction

References

Beard, D. J. et al. 2018. Arthroscopic subacromial decompression for subacromial shoulder pain (CSAW): a multicentre, pragmatic, parallel group, placebo-controlled, three-group, randomised surgical trial. The Lancet 391(10118), pp. 329-338. doi: 10.1016/S0140-6736(17)32457-1

Brindisino, F. et al. 2026. Beyond the capsule: an integrated perspective on the wide world of frozen shoulder. A collaborative viewpoint. Pain Management, pp. 1-20. doi: 10.1080/17581869.2026.2636725

Corbacho, B. et al. 2021. Cost-effectiveness of surgical treatments compared with early structured physiotherapy in secondary care for adults with primary frozen shoulder : an economic evaluation of the UK FROST trial. Bone Jt Open 2(8), pp. 685-695. doi: 10.1302/2633-1462.28.Bjo-2021-0075.R1

Date, A. and Rahman, L. 2020. Frozen shoulder: overview of clinical presentation and review of the current evidence base for management strategies. Future Sci OA 6(10), p. Fso647. doi: 10.2144/fsoa-2020-0145

Hamed-Hamed, D. et al. 2026. Impact of nutritional profile on pain and functionality in patients with frozen shoulder: a cross-sectional observational study. Frontiers in Medicine Volume 13 - 2026,  doi: 10.3389/fmed.2026.1785577

King, W. V. and Hebron, C. 2023. Frozen shoulder: living with uncertainty and being in “no-man’s land”. Physiotherapy Theory and Practice 39(5), pp. 979-993. doi: 10.1080/09593985.2022.2032512

Navarro-Ledesma, S. 2025a. Frozen Shoulder as a Systemic Immunometabolic Disorder: The Roles of Estrogen, Thyroid Dysfunction, Endothelial Health, Lifestyle, and Clinical Implications. J Clin Med 14(20),  doi: 10.3390/jcm14207315

Navarro-Ledesma, S. 2025b. Frozen Shoulder as a Systemic Immunometabolic Disorder: The Roles of Estrogen, Thyroid Dysfunction, Endothelial Health, Lifestyle, and Clinical Implications. Journal of Clinical Medicine 14(20), p. 7315. 

Pandey, V. and Madi, S. 2021. Clinical Guidelines in the Management of Frozen Shoulder: An Update! Indian J Orthop 55(2), pp. 299-309. doi: 10.1007/s43465-021-00351-3

Razzak, Z. A. et al. 2019. Effect of aerobic and anaerobic exercise on estrogen level, fat mass, and muscle mass among postmenopausal osteoporotic females. Int J Health Sci (Qassim) 13(4), pp. 10-16. 

Salamh, P. et al. 2025. An international consensus on the etiology, risk factors, diagnosis and Management for individuals with Frozen Shoulder: a Delphi study. J Man Manip Ther 33(4), pp. 309-320. doi: 10.1080/10669817.2025.2470461

Wend, K. et al. 2012. Tissue-Specific Effects of Loss of Estrogen during Menopause and Aging. Frontiers in Endocrinology Volume 3 - 2012,  doi: 10.3389/fendo.2012.00019