Placebo in Physiotherapy: How Much of What We Do Is Actually Placebo?

August 19, 2026

When we hear the word placebo, most people imagine a sugar pill: an inactive treatment given to somebody who believes they are receiving a real medication.

But placebo is much more interesting than that.

Physiotherapy never happens in isolation. A patient enters a clinical environment, meets a therapist, forms expectations, receives explanations, experiences touch or movement, and develops beliefs about whether the treatment is likely to help.

All of these factors surround the specific treatment itself.

This raises an important question:

When a patient improves after physiotherapy, how much of that improvement comes from the intervention itself, and how much comes from the context in which that intervention is delivered?

The answer is more complicated than saying physiotherapy either “works” or is “just placebo.”

If you want to watch a VIDEO instead of reading, here is the deep dive video: https://www.youtube.com/watch?v=9N1PUSAZBLE

What Is a Placebo?

A placebo is generally an inert or inactive intervention used within a therapeutic or experimental context.

Despite lacking the specific active component being investigated, placebo interventions can still be associated with changes in symptoms.

There are several important forms of placebo.

Open-label placebo

With an open-label placebo, the patient knows that the intervention is a placebo.

There is no deception. The person is explicitly told that the treatment does not contain the specific active ingredient normally expected to create the therapeutic effect.

Interestingly, placebo responses can still occur under some open-label conditions.

Concealed placebo

In a blinded experiment, the patient may not know whether they are receiving an active treatment or an inactive placebo.

This allows researchers to estimate how much of the treatment response may be attributable to the specific intervention compared with the surrounding context.

Deceptive placebo

A deceptive placebo occurs when an inactive intervention is presented to the patient as though it were an active treatment.

Although this has historically been important in placebo research, deception creates obvious ethical problems in clinical practice.

Nocebo

The opposite phenomenon is the nocebo effect.

Negative expectations can contribute to worse symptom experiences or perceived adverse effects.

This immediately demonstrates something clinically important:

The effect of treatment may not depend exclusively on the physical intervention being delivered.

What Influences the Placebo Response?

The placebo response is not random.

Several psychological, biological and contextual factors may contribute.

Expectations

Patients rarely arrive at a physiotherapy clinic without expectations.

They may have:

spoken to friends or family,
previously undergone similar treatment,
researched their symptoms online,
received a diagnosis from another healthcare professional,
or already formed strong beliefs about what will or will not help them.

A patient who expects an intervention to help may experience treatment differently from somebody convinced that it will fail.

Expectations do not mean that symptoms are imaginary.

Rather, expectation is one of many factors capable of influencing how the nervous system processes and interprets sensory information.

Conditioning and Previous Experiences

Previous treatment experiences can also influence subsequent responses.

If somebody has repeatedly undergone a particular intervention and experienced pain relief afterward, the treatment itself—and potentially the environment surrounding it—can become associated with improvement.

The treatment table, clinical environment, therapist, equipment or ritual may all become signals associated with what happened previously.

This is one mechanism through which conditioning may contribute to placebo responses.

The Clinician–Patient Interaction Matters

Imagine two physiotherapists providing essentially the same exercise program.

The first therapist performs a thorough assessment, listens carefully to the patient, explains the reasoning behind the program and gives the patient a clear idea of what to expect.

The second therapist simply says:

“We'll try some exercises and see if they help.”

The exercise program might technically be identical.

But the therapeutic context is not.

Communication can influence:

expectations,
confidence,
fear,
motivation,
adherence,
perceived credibility,
and the overall treatment experience.

This does not mean physiotherapists should exaggerate or promise outcomes they cannot guarantee.

Quite the opposite.

The goal should be to create realistic positive expectations while remaining scientifically and ethically accurate.

Perceived Credibility and the Therapeutic Environment

Patients also interpret the clinician and the environment around them.

Qualifications, professionalism, confidence, communication and the appearance of the clinical setting may all affect how credible an intervention appears.

This does not mean putting certificates on the wall directly treats pain.

It means the patient is constantly interpreting signals about:

“Does this person understand my problem?”

“Does this treatment make sense?”

“Am I safe here?”

“Is this likely to help me?”

These perceptions can influence the overall treatment context.

To Understand Placebo, We Need to Understand Pain

Pain is not simply a direct measurement of tissue damage.

The International Association for the Study of Pain defines pain as both a sensory and emotional experience.

This distinction is important because two people can experience the same apparent injury or stimulus very differently.

A numerical pain scale therefore does not provide an objective measurement that can easily be compared between individuals.

One person's 8/10 is not necessarily equivalent to another person's 8/10.

Clinically, pain scales may be more useful when tracking change within the same person over time.

Pain and Nociception Are Not the Same Thing

One of the most important concepts in pain science is the distinction between pain and nociception.

Nociception

Nociception refers to the neural processes involved in detecting and transmitting information about potentially harmful stimuli.

Pain

Pain is the conscious sensory and emotional experience.

They are related, but they are not identical.

Nociceptive information can travel from peripheral tissues toward the spinal cord and brain, but that information can be modified at multiple stages along the pathway.

The nervous system is not simply a cable carrying a fixed quantity of “pain” from an injured structure to the brain.

It is a dynamic processing system.

Descending Pain Modulation

Pain processing does not only travel upward from the body toward the brain.

The brain can also influence processing in the opposite direction.

Descending pathways from higher brain regions and the brainstem can influence the processing of nociceptive information within the spinal cord.

Therefore, the same peripheral input does not necessarily have to result in exactly the same pain experience every time.

Pain can be influenced by:

attention,
emotion,
expectations,
previous experience,
threat perception,
context,
and endogenous pain-modulatory mechanisms.

This becomes particularly relevant when discussing placebo analgesia.

Peripheral Sensitization

In peripheral sensitization, nociceptors in peripheral tissues become more responsive.

After tissue injury or inflammation, inflammatory mediators can lower the activation threshold of nociceptors.

This means that stimuli may produce a greater nociceptive response than they would under normal conditions.

One clinical consequence may be hyperalgesia—an increased response to a stimulus that would normally already be painful.

Central Sensitization

Central sensitization refers to increased responsiveness of nociceptive neurons within the central nervous system.

Persistent or repeated nociceptive input can contribute to altered processing within the spinal cord and other central structures.

Two concepts commonly discussed in relation to sensitization are:

Hyperalgesia

A stimulus that is normally painful becomes more painful than expected.

Allodynia

A stimulus that would normally not provoke pain—such as light touch—becomes painful.

These phenomena demonstrate why persistent pain cannot always be explained simply by continuing tissue damage.

The nervous system itself may change how incoming information is processed.

How Could Placebo Affect Pain?

This is where placebo becomes much more interesting than the idea that somebody simply “thinks” they feel better.

Expectation of pain relief can recruit higher-order brain processes and descending pain-modulatory pathways.

A simplified model looks like this:

Expectation of pain relief
↓
Higher cortical processing
↓
Brainstem pain-modulatory systems
↓
Descending modulation
↓
Altered nociceptive transmission in the spinal cord
↓
Potential reduction in experienced pain

Placebo analgesia can therefore involve measurable neurophysiological processes.

It is not evidence that the patient's pain was fake.

Can Placebo Reverse Central Sensitization?

This is a much more difficult question.

If descending pain modulation can temporarily reduce nociceptive transmission in a sensitized system, could repeated exposure eventually contribute to longer-term changes?

Or does placebo primarily modulate pain temporarily without reversing the underlying sensitization?

At present, this distinction should be treated cautiously.

Evidence that placebo can reduce pain within a sensitized system is not equivalent to evidence that placebo can reverse central sensitization itself.

This is an area where further research is needed.

Placebo and Physiotherapy

Physiotherapy is particularly interesting in this context because many of our interventions combine:

touch,
movement,
education,
expectations,
therapeutic ritual,
human interaction,
and specific physical interventions.

To understand how much contextual effects matter, it is useful to examine the different components of physiotherapy separately.

Touch in Physiotherapy

Touch is one of the most obvious differences between physiotherapy and many other healthcare interventions.

A large systematic review and multivariate meta-analysis examined the physical and mental-health effects of touch interventions across a substantial body of research.

The review reported beneficial associations across several outcomes and found that human touch and touch delivered through objects or robots did not necessarily produce identical effects, particularly for some mental-health outcomes. [1]

This does not prove that manual therapy works primarily because of touch.

But it does demonstrate that touch itself is biologically and psychologically relevant.

Is Manual Therapy Just Placebo?

Manual therapy is especially difficult to investigate because designing a convincing placebo treatment is surprisingly complicated.

Imagine testing a manual therapy technique against a sham treatment.

Researchers must decide:

Does the sham therapist touch the patient?
How much pressure should they apply?
How long should the contact last?
Does the therapist know they are delivering placebo?
Does knowing this change their confidence or communication?
Can the patient tell which intervention seems more credible?

A systematic review and meta-analysis examining manual therapy in placebo-controlled trials highlighted significant problems with sham-treatment design and inconsistent assessment of expectations. [2]

The authors found that some manipulation techniques did not demonstrate superior effects compared with sham interventions, whereas the evidence differed for other manual therapy techniques.

The important conclusion is not:

“Manual therapy is placebo.”

It is that separating specific treatment effects from contextual effects in manual therapy research is extremely difficult.

Spinal Manipulation and Mobilization

One randomized clinical trial investigated spinal manipulation and mobilization in young adults with mild-to-moderate chronic low-back pain.

Participants were allocated to spinal manipulation, spinal mobilization or placebo control groups.

The trial did not find evidence that manipulation or mobilization produced superior reductions in pain or disability compared with the placebo intervention. [3]

This does not establish that every form of spinal manipulation is ineffective for every patient.

It demonstrates that the effectiveness of an intervention needs to be judged according to:

the patient population,
condition,
comparison treatment,
outcome,
and study design.

Exercise Therapy and Contextual Effects

Exercise therapy differs from passive manual therapy because the patient is actively moving.

Exercise may influence:

strength,
physical capacity,
endurance,
mobility,
function,
confidence,
and beliefs about movement.

It can also provide a patient with new experiences.

Imagine somebody with persistent back pain who believes that squatting will damage their spine.

If they gradually perform a squat safely and successfully, they receive new information:

“I can do this movement.”

That experience may itself be therapeutically valuable.

But exercise also occurs within a therapeutic context.

The therapist explains the movement.

The therapist provides feedback.

The patient develops expectations.

The therapist encourages—or potentially frightens—the patient.

A 2024 systematic review and meta-analysis investigated contextual effects in exercise therapy for low-back pain and concluded that a substantial proportion of improvement in pain and disability may be attributable to contextual effects. However, the certainty of evidence was low, meaning the magnitude of those estimates should be interpreted cautiously. [4]

The correct conclusion is therefore not:

“Exercise is mostly placebo.”

Exercise has therapeutic effects of its own.

But how exercise is delivered may also influence the outcome.

Manual Therapy vs Exercise Therapy

A randomized controlled trial compared manual therapy with therapeutic exercise in people with nonspecific chronic neck pain.

Both approaches produced improvements.

The study found no major overall differences between groups in the short and medium term, although manual therapy appeared to reduce perceived pain faster, while therapeutic exercise reduced disability faster. [5]

This supports the idea that different interventions may influence different outcomes and may potentially be useful at different stages of rehabilitation.

Mobilisation With Movement and Exercise vs Sham Treatment

Another randomized trial examined people with shoulder pain.

Participants receiving mobilisation with movement combined with exercise experienced greater improvements in several measures of pain and function than participants receiving sham mobilisation with movement combined with exercise. [6]

This is important because it demonstrates the opposite side of the placebo discussion:

Some physiotherapy interventions can produce outcomes that exceed those seen with carefully designed sham treatments.

Therefore, contextual effects do not explain everything.

TENS and Placebo

Transcutaneous electrical nerve stimulation, or TENS, is commonly used in physiotherapy for pain.

The ETRELKA randomized clinical trial compared TENS with placebo TENS in people with symptomatic knee osteoarthritis.

The study did not demonstrate superior improvement in knee pain with TENS compared with placebo TENS. [7]

This suggests clinicians should consider whether other interventions may provide more meaningful benefits for this particular population.

Radial Shockwave Therapy

A randomized double-blind placebo-controlled trial investigated radial shockwave therapy for myofascial pain syndrome.

The researchers did not find significant differences between the shockwave and placebo groups across the reported follow-up outcomes. [8]

Again, this does not mean every indication for shockwave therapy is ineffective.

It means that for a particular condition, protocol and study population, the specific treatment did not clearly outperform placebo.

High-Intensity Laser Therapy

High-intensity laser therapy is another modality used within physiotherapy.

A randomized double-blind placebo-controlled trial investigated whether adding high-intensity laser therapy to conventional physiotherapy provided additional benefit in people with knee osteoarthritis.

Both groups improved, but the addition of high-intensity laser therapy did not produce significant additional short- or medium-term improvements in pain or function compared with the placebo condition. [9]

This raises an important clinical question:

If the rehabilitation program itself produces improvement, does adding another modality meaningfully improve the outcome?

Therapeutic Ultrasound

Therapeutic ultrasound has been used in physiotherapy for decades.

A Cochrane systematic review investigating therapeutic ultrasound for chronic nonspecific low-back pain concluded that evidence regarding pain was uncertain.

There was some evidence of small short-term effects on function compared with placebo, but the certainty of that evidence was very low.

Overall, the review concluded that the available evidence did not support the routine use of therapeutic ultrasound for chronic low-back pain. [10]

So What Actually Causes Improvement?

After looking at manual therapy, exercise and physical modalities, the central question becomes:

When a patient improves, what caused the improvement?

Was it:

the specific intervention?
touch?
expectations?
conditioning?
natural recovery?
the therapist–patient interaction?
movement exposure?
reassurance?
regression to the mean?
increased confidence?
or some combination of these?

In reality, clinical outcomes are rarely produced by only one mechanism.

A useful way to conceptualize treatment is:

Specific treatment effects
+
Contextual effects
+
Natural history and recovery
+
Patient-specific factors

Observed clinical outcome

The contribution of each component will differ depending on the intervention, condition and patient.

Is Physiotherapy Placebo?

Yes, placebo and contextual effects exist within physiotherapy.

But that statement needs to be interpreted correctly.

It does not mean:

“Physiotherapy doesn't work.”

It means that a patient's response to physiotherapy can be influenced both by the specific intervention and by the context surrounding that intervention.

And importantly, different treatments appear to have different relationships with placebo.

Some interventions outperform sham treatments.

Others do not.

Some areas still have insufficient evidence.

Therefore, the scientifically useful question is not:

“Is physiotherapy placebo?”

It is:

“How much of the effect of this specific intervention, for this specific condition, comes from the intervention itself—and how much comes from the surrounding treatment context?”

Contextual Effects Should Improve Physiotherapy, Not Replace It

Understanding placebo should not encourage clinicians to abandon evidence-based practice.

It should encourage us to improve it.

A physiotherapist should still:

select interventions based on evidence,
perform appropriate assessment,
monitor outcomes,
progress rehabilitation appropriately,
recognize red flags,
and refer when necessary.

But clinicians can also improve the contextual side of treatment.

We can:

listen carefully to the patient's experience,
communicate clearly,
avoid unnecessary fear-inducing language,
provide understandable explanations,
individualize rehabilitation,
create realistic positive expectations,
demonstrate progress,
improve adherence,
use touch appropriately,
and create a professional therapeutic environment.

These factors do not replace good clinical treatment.

They are part of good clinical treatment.

Physiotherapy May Need to Teach More Than Techniques

Physiotherapy education often focuses heavily on technical skills:

Where should we mobilize?

Which exercise should we prescribe?

How much force should we use?

Which modality should we select?

These questions matter.

But perhaps we need to pay more attention to another set of questions:

How do we communicate with patients?

How do we explain pain without creating fear?

How do we establish realistic expectations?

How does our behavior influence the therapeutic experience?

How do we distinguish specific therapeutic effects from contextual effects?

And perhaps most importantly:

Can we become better physiotherapists not only by learning more techniques, but by becoming better at delivering the treatments we already know?

That may be one of the most clinically useful lessons from studying placebo in physiotherapy.

Watch the Full Deep Dive

I explore this topic in much greater detail in my full video, including:

placebo and nocebo,
pain vs nociception,
descending pain modulation,
peripheral and central sensitization,
placebo and sensitization,
touch,
manual therapy,
exercise therapy,
TENS,
shockwave therapy,
laser therapy,
and therapeutic ultrasound.

Watch: “How Much of Physiotherapy Is Placebo?”

References

1. Packheiser J, Hartmann H, Fredriksen K, et al. A systematic review and multivariate meta-analysis of the physical and mental health benefits of touch interventions. Nature Human Behaviour. 2024;8:1088–1107.

2. Molina-Álvarez M, Arribas-Romano A, Rodríguez-Rivera C, et al. Manual Therapy Effect in Placebo-Controlled Trials: A Systematic Review and Meta-Analysis. International Journal of Environmental Research and Public Health.

3. Thomas JS, Clark BC, Russ DW, France CR, Ploutz-Snyder R, Corcos DM; RELIEF Study Investigators. Effect of Spinal Manipulative and Mobilization Therapies in Young Adults With Mild to Moderate Chronic Low Back Pain: A Randomized Clinical Trial. JAMA Network Open. 2020;3(8):e2012589.

4. de Roode A, Heymans MW, van Lankveld W, et al. The impact of contextual effects in exercise therapy for low back pain: a systematic review and meta-analysis. BMC Medicine. 2024;22:484.

5. Bernal-Utrera C, Gonzalez-Gerez JJ, Anarte-Lazo E, Rodriguez-Blanco C. Manual therapy versus therapeutic exercise in non-specific chronic neck pain: a randomized controlled trial. Trials. 2020;21.

6. Baeske R, Hall T, Dall’Olmo RR, Silva MF. In people with shoulder pain, mobilisation with movement and exercise improves function and pain more than sham mobilisation with movement and exercise: a randomised trial. Journal of Physiotherapy. 2024;70(4):288–293.

7. Reichenbach S, Jüni P, Hincapié CA, et al. Effect of transcutaneous electrical nerve stimulation (TENS) on knee pain and physical function in patients with symptomatic knee osteoarthritis: the ETRELKA randomized clinical trial. Osteoarthritis and Cartilage. 2022.

8. Ogbeivor C, AlMubarak H, Akomolafe T, et al. The effectiveness of radial shockwave therapy on myofascial pain syndrome: a two-armed, randomized double-blind placebo-controlled trial. BMC Musculoskeletal Disorders. 2025;26:413.

9. Özgözen S, Özgözen AL, Analan PD, et al. Additional effect of high-intensity laser therapy with conventional physiotherapy related to pain and function in patients with knee osteoarthritis: a randomized, double-blind, placebo-controlled, 12-week follow-up study.

10. Ebadi S, Henschke N, Forogh B, et al. Therapeutic ultrasound for chronic low back pain. Cochrane Database of Systematic Reviews. 2020.

Medical disclaimer: This article is intended for educational purposes only and does not constitute individualized medical advice, diagnosis or treatment. The effectiveness of physiotherapy interventions varies according to the condition, patient population, treatment protocol and clinical context.

Back to blog