Why is the rectus femoris vulnerable?

Unlike the other quadriceps muscles, the rectus femoris crosses both the hip and the knee joints.

This means that during sprinting it is required to:

1. Generate force at the hip
2. Generate force at the knee
3. Transfer force between both joints
4. Tolerate high speeds and rapid movement

Researchers suggest this ‘biarticular’ design is one reason the muscle is particularly prone to injury during explosive sporting activities.

Several factors may increase the risk of a rectus femoris strain, including previous injury, reduced flexibility, deficits in eccentric strength (the muscle’s ability to control force while lengthening) and strength imbalances between limbs.

Importantly, these factors do not automatically cause injury. Rather, they influence how much load a muscle can tolerate before an injury occurs.

More Than Just Strength: Understanding Capacity

One of the biggest misconceptions in sport is that injuries occur because a muscle isn’t strong enough.

While strength is important, modern sports medicine suggests the relationship is far more complex. A useful concept is the difference between strength and capacity.

– Strength refers to how much force a muscle can produce.
– Capacity refers to how much stress the entire system can tolerate over time.
– Capacity is influenced by factors such as strength, sprint exposure, training history, recovery, fatigue, sleep and previous injuries.

This means that someone can be very strong in the gym but still sustain a muscle strain if the demands being placed on their body exceed what it has recently been prepared for.

Australian Sports Scientist Dr Tim Gabbett highlighted that injuries are often best understood through the interaction between training load and physical capacity, rather than either factor in isolation.

A Real-World Example

I was recently reminded of this lesson myself after spending some time away from football and instead prioritising gym training and a gradual return to running. In returning to football, I strained my rectus femoris during an acceleration effort at training. At the time, my body felt tired, running was effortful and upon reflection I could see that the demands I placed on the muscle had exceeded its current capacity.

Less than a week later, I attempted to return to playing a match as the pain had settled, without training prior, and experienced a flare up. The muscle had not yet regained the capacity required for the demands of the game.

It was a valuable reminder of a lesson I discuss regularly with patients:

Recovery is not just about settling pain, it’s about restoring the capacity to meet the demands of the activity you want to return to.

Whether someone is returning to football, running, gym, or even a physically demanding job, the same principle applies. Feeling better is an important milestone, but it is not always the same as being ready.

The Role of Training Load

Training load refers to the total stress placed on the body through training, sport and competition.

Research consistently shows that large spikes in training load are associated with an increased risk of injury. When training loads increase too quickly, fatigue accumulates, eccentric muscle strength may decrease, neuromuscular control can be affected and movement quality may decline. Conversely, gradually increasing training load allows the body to adapt. Over time, higher chronic training loads can improve strength, fitness and resilience, ultimately reducing injury risk.

This is one reason why elite football clubs spend so much time monitoring player workloads throughout the season.

What Can We Learn from Football?

A 2023 study examining rectus femoris injuries in professional footballers found that 80% occurred during kicking, 10% during sprinting and 10% during changes of direction.

Despite kicking being the most common mechanism, all three movements share one characteristic; They require the rectus femoris to tolerate high forces at high speed.

This highlights an important principle that applies well beyond football:

Injuries don’t necessarily occur because movement is dangerous. They often occur when the demands of movement exceed the body’s current capacity.

The same concept applies to everyday activities. People may experience injury after returning to the gym after time off, increasing running volume rapidly, tackling a physically demanding weekend project or returning to sport after a break.

The issue is often not the activity itself, but the gap between what the body is asked to do and what it is prepared to do.

How This Influences Physiotherapy Practice

My interest in football has reinforced the importance of looking beyond symptoms when assessing injuries.

Rather than focusing solely on where pain is located, it is often more useful to ask:

“What demands is this person trying to return to?”

For a footballer, rehabilitation isn’t complete when walking is comfortable. The muscle must eventually tolerate:

1. Accelerating
2. Sprinting
3. Kicking
4. Repeated high-speed efforts

This is why rehabilitation should be progressive and specific to the individual’s goals.

As discussed in professional football injury-prevention models, one of the most challenging phases of rehabilitation is the transition from the gym environment back into full training and competition demands. Whether you’re a professional or grass roots footballer, successfully bridging this gap requires careful progression to ensure the athlete has sufficient capacity for the demands of play.

Final thoughts

Football is a game built on speed, power and explosive movement. While these qualities make the sport exciting, they also place significant demands on muscles such as the rectus femoris.

Perhaps the most important lesson from both football and physiotherapy is that injury risk is not simply about strength or flexibility in isolation. It is understanding the relationship between what the body can currently tolerate and the demands placed upon it, that should be prioritised.

By gradually building capacity, managing training loads appropriately and progressing rehabilitation in a structured way, athletes and active individuals can reduce injury risk and improve their ability to perform at their best.

At Thriving Lives Co. in Bungalow, Cairns, we help athletes and active people understand their injuries, rebuild capacity and safely return to the activities that matter to them.

If you require support with injury recovery, return to sport, or training load management, the Physiotherapy team at Thriving Lives Co can provide tailored guidance to help you recover, perform and stay active with confidence.

 References

1. Mendiguchia J, Alentorn-Geli E, Idoate F, Myer GD. Rectus femoris muscle injuries in football: a clinically relevant review of mechanisms of injury, risk factors and preventive strategies. Br J Sports Med. 2013.
2. Jokela A, et al. Indirect Rectus Femoris Injury Mechanisms in Professional Soccer Players: Video Analysis and Magnetic Resonance Imaging Findings. Clin J Sport Med. 2023.
3. Gabbett TJ. Training load and injury: understanding the relationship between capacity and load. Various publications and commentaries on the training-injury prevention paradox.
4. BJSM Podcast. Practical Tips for In-Season Injury Prevention and Monitoring Professional Football Players.

Kate Spring
Physiotherapist
Thriving Lives Co. 
Bungalow, Cairns

What is the gut-disc axis?

The gut-disc axis is a proposed biological pathway linking gut health to intervertebral disc health and low back pain.

In simple terms, it suggests that:

– The gut microbiome influences immune and inflammatory processes
– These inflammatory signals may affect spinal tissues, including intervertebral discs (the substance that sits between each vertebrae)
– Over time, this may contribute to pain sensitisation and persistent low back pain

While still an emerging concept, it aligns with broader research showing that chronic pain is influenced by whole-body inflammatory and neurological processes, not just local tissue changes.

Why researchers are looking beyond the spine for back pain causes

Traditionally, low back pain management has focused on disc degeneration, joint or muscle injury and nerve compression visible on imaging, however, many people with chronic low back pain have:

– Normal or only mild imaging findings
– Persistent pain that does not match structural changes
– Fluctuating symptoms influenced by stress, lifestyle, and general health

This has led researchers and clinicians to investigate systemic contributors to pain, including inflammation and gut health.

What this study found

This pilot study compared 28 people with chronic low back pain, with 28 healthy, matched controls

Importantly, participants with low back pain did not have advanced spinal degeneration, meaning their pain was not explained by severe structural changes alone.

Researchers analysed stool samples to understand what the participants gut microbiome environment was like.

Key findings: gut microbiome differences in chronic low back pain

1. Reduced gut microbial diversity

People with chronic low back pain showed lower gut microbial diversity compared to healthy individuals.

Lower diversity is commonly associated with:

– Increased systemic inflammation
– Reduced resilience of the gut microbiome
– Greater risk of chronic disease

This suggests a less balanced gut environment in people experiencing persistent pain.

2. Increased pro-inflammatory bacteria

The study found higher levels of bacterial groups linked to inflammation, including:

– Proteobacteria
– Desulfobacterota
– Prevotella

These bacteria have been associated in other research with immune activation and inflammatory signalling.

3. Reduced beneficial bacteria

Lower levels of beneficial, gut-protective bacteria were also observed, including:

– Bacteroidota
– Parabacteroides

These bacteria are involved in maintaining the gut lining, producing anti-inflammatory compounds and reducing inflammation levels and supporting immune regulation.

How could gut health influence back pain?

The proposed mechanism involves several steps:

1. Gut imbalance (dysbiosis) – Changes in gut bacteria reduce protective functions and increase inflammatory activity.

2. Increased intestinal permeability – A weakened gut barrier may allow bacterial products to enter the bloodstream.

3. Systemic inflammation – The immune system responds by releasing inflammatory chemicals throughout the body.

4. Effects on spinal tissues -These inflammatory signals may, sensitise pain pathways – making you more prone to feeling pain, increase inflammation around spinal structures and influence your spines disc health.

5. Persistent pain cycle – over time, this may contribute to chronic low back pain, even in the absence of major structural abnormalities.

What this means for people with chronic low back pain

For patients attending physiotherapy, exercise physiology, or allied health services at Thriving Lives Co in Cairns, this research reinforces an important clinical message; chronic low back pain is often influenced by multiple systems in the body and not just the spine.

This aligns with modern pain science and the biopsychosocial model used in contemporary practice – where we focus on the whole person in a holistic approach.

It helps explain why effective management often includes:

– Graded exercise therapy
– Education about your body, pain, stress, inflammation and general health
– Stress and sleep management
– Lifestyle modification

Can you treat low back pain by targeting gut health?

Yes & no – this research reinforces our messaging around the importance of holistic health to support your bodies internal environment, which may reduce inflammation levels and reduce your level of pain. It isn’t the sole treatment of your back pain, but at times may be worth exploring:

– Dietary interventions to support microbiome diversity
– Probiotic or prebiotic strategies
– Exercise programs that influence systemic inflammation
– Stress reduction strategies (which also affect gut function)

Importantly, these approaches are best considered adjuncts to evidence-based physiotherapy and exercise rehabilitation-not replacements. Meaning they form a small piece of a larger puzzle.

The take-home message

This study adds to growing evidence that chronic low back pain is not purely a structural problem.

Instead, it may involve:

– Immune system activation
– Gut microbiome changes
– Nervous system sensitisation
– Lifestyle and behavioural factors

The emerging gut–disc axis hypothesis provides new insight into understanding the complexities of chronic pain, and how we can best support individuals to thrive by targeting the whole system.

How Thriving Lives Co in Cairns approaches low back pain

At Thriving Lives Co, our multidisciplinary team integrates:

– Physiotherapy
– Exercise physiology
– Occupational therapy
– Psychology

This allows us to address low back pain from multiple perspectives, including:

– Movement and strength
– Load management
– Pain education
– Psychological and behavioural factors
– Lifestyle influences on recovery

This aligns closely with modern research suggesting chronic pain is a system-wide condition, not just a local tissue issue.

Conclusion

The relationship between gut health and chronic low back pain remains an emerging area of research suggesting that gut health may play a role in chronic low back pain through systemic inflammation and immune pathways.

While still in early stages, this study provides further evidence that effective management of chronic pain may require a whole-body, multidisciplinary approach – consistent with the model of care used at Thriving Lives Co. If you’re in need of assistance with back pain, whether in Cairns locally, or online – reach out to find out more or make a booking.

Research source:
Sima S, et al. (2026). Patients With Chronic Low Back Pain Without Advanced Disk Degeneration Exhibit Gut Microbiome Dysbiosis: Evidence From an Age-, Sex-, and BMI-Matched Pilot Study. JOR Spine, 9(2), e70174.

Kadell Pearce
Physiotherapist
Thriving Lives Co. 
Bungalow, Cairns

What is Dry Needling?  

Dry needling is a technique used by qualified clinicians to treat myofascial trigger points – tight, overactive points / knots within muscles that can contribute to pain and restricted movement. A fine, sterile needle is inserted into the muscle to help reduce pain sensitivity and tension, improve blood flow, and normalise muscle activity. Slightly different than acupuncture, which is based on traditional Chinese medicine and aiming to improve energy flow (Qi) along meridians, dry needling is grounded in modern western medicine and evidence-based practice to relieve muscle tension and desensitise overactive muscles.  

Why thoracic dry needling safety requires special care  

The thoracic region contains vital structures including the lungs. Muscles such as the trapezius, rhomboids, and intercostals lie close to these structures. As a result, there is a small but important risk of complications such as pneumothorax (collapsed lung) if needling is performed incorrectly. This is why only appropriately trained clinicians should perform dry needling in this area. 

How Qualified Physiotherapists Approach Safe Needling  

Through my recent APA training, one of the key messages was that safe needling is not just about technique – it’s also about clinical reasoning and safety awareness. 

Physiotherapists follow several important safety principles when considering dry needling: 

1. Understanding of anatomical knowledge

A strong understanding of muscle layers, bones positioning, nerve innervation and other anatomical structures is essential. 

2. Controlled needle direction and depth

Needles are inserted with careful consideration of angle and depth to avoid deeper structures like the lungs and pleura. 

3. Appropriate positioning

Patient positioning (such as prone lying) helps optimise both access and safety. 

4. Individual assessment& Informed consent

Not every patient is suitable for dry needling. A thorough initial assessment and informed consent should always completed beforehand. 

5. Ongoing monitoring

Patients are monitored by the therapist during and after treatment to ensure safety and comfort.  

The Importance of Informed Consent and Patient Education 

Another key aspect of safe needling practice is ensuring that patients are fully informed before treatment begins. This includes discussing not only the potential benefits, but also the risks associated with needling in sensitive areas like the thorax area. Patients should understand what to expect during and after treatment, as well as what symptoms would warrant seeking medical attention. Clear communication also includes advising patients to remain still during needling and to avoid sudden movements such as deep breathing, coughing, or repositioning while needles are in place. This shared understanding helps reduce risk and ensures patients feel confident and informed throughout their needling treatment. 

Understanding Pneumothorax Risk and Early Recognition 

Although rare (0.01/10000 treatments), pneumothorax is the most significant complication associated with thoracic needling, and early recognition is essential. Symptoms may not always appear immediately and can develop over several hours following needling treatment. Patients may experience signs such as chest pain, shortness of breath, dry cough, dizziness, or increased respiratory rate. In more severe cases, changes such as reduced breath sounds or signs of respiratory distress may occur. While most cases are mild and resolve with appropriate medical management, some may require interventions such as oxygen therapy or drainage. This highlights why both clinician awareness and patient education are critical components of safe practice. 

Why Needle Angle and Depth Matter in the Thorax 

One of the most important concepts I took away from recent training is how significantly needle angle influences depth of penetration. Even when using the same needle length, a steeper angle (closer to perpendicular) can result in much deeper tissue penetration compared to a gentler angle. In the thoracic region, where structures such as the lungs sit relatively close to the surface, this becomes highly clinically relevant. Small changes in angle can mean the difference between staying within muscle tissue or reaching deeper, higher-risk structures. For this reason, guidelines suggested clinicians to use controlled angles, shorter needles where appropriate, and a clear understanding of underlying anatomy to ensure needling remains within safe limits. 

Applying Safety Principles in Clinical Practice 

Current recommendations for thoracic dry needling safety emphasise several practical strategies. These include using needling on one side or same side of body to reduce risk, selecting safer anatomical zones such as the region around the vertebrae, and applying oblique or angled techniques rather than perpendicular insertion where appropriate. Additionally, clinicians are encouraged to work within a proportion of the “safe depth” (often less than 70% of the estimated risk depth) and to adjust their approach based on individual patient characteristics like body size. Ultimately, safe practice relies on a combination of technical skill, anatomical understanding, patient education, and clinical awareness. 

A Holistic Physiotherapy Approach 

In physiotherapy, dry needling is not used in isolation. Dry needling will be more effective in reducing muscle pain and improving function when used as part of a broader physiotherapy treatment plan. Physiotherapists usually combine it with other treatments such as exercise therapy, manual therapy such as joint mobilisation or manipulation, activity modification and education. This approach helps address the root cause of the pain and supports long-term recovery rather than just temporary relief. 

Are you experiencing upper / mid-back pain?  

If you are experiencing upper or mid-back pain, a thorough physiotherapy assessment can help identify the best approach for your management. Our Physiotherapy team at Thriving Lives Co. are dry needling-trained and able to provide safe, evidence-based dry needling when appropriate.    

Justin So 
Physiotherapist 
Thriving Lives Co. 
Bungalow, Cairns

Article written by,

Lucy Ruttiman
Mental Health Endorsed Occupational Therapist
Pain Reprocessing Therapy Certified Therapist
Thriving Lives Co.
Bungalow, Cairns