Tecar Therapy: How It Works and When It Is Needed

Tecar therapy

Tecar therapy is one of the most widespread instrumental therapies in physiotherapy and rehabilitation. The term TECAR is an acronym for Transfer of Capacitive and Resistive Energy: it is a form of endogenous diathermy that generates heat within biological tissues, exploiting the principle of the capacitor, to promote natural repair processes and reduce pain. Since its introduction in Italy in the early 2000s, tecar therapy has gained a prominent role in physiotherapy clinics, sports centers, and rehabilitation facilities, becoming one of the most requested tools by both athletes and the general population.

Unlike other instrumental therapies that radiate energy from the outside (such as laser or ultrasound), tecar therapy stimulates the tissue from within, generating a movement of endogenous electrical charges that produces a controlled increase in temperature. This mechanism activates vasodilation, improves cellular metabolism, and accelerates the reabsorption of edema and effusions. The result is a reduction in pain, an improvement in mobility, and an acceleration of healing times.

It is important to emphasize from the outset that tecar therapy is not a “miraculous” therapy and does not replace active rehabilitation. The scientific evidence supporting it is growing but still moderate, and the best results are obtained when it is used in combination with manual therapy and therapeutic exercise. In case of pain or functional limitation, it is always advisable to consult your doctor or physical therapist for a personalized evaluation.

What is Tecar Therapy

Definition and Origin

Tecar therapy is a method of endogenous electrotherapy based on the physical principle of the capacitor. The TECAR device generates a high-frequency electromagnetic field (typically 0.5 MHz) that passes through the biological tissues interposed between an active electrode (applied to the area to be treated) and a return plate (positioned on the opposite side). The passage of current through the tissues causes a movement of ions and polar molecules (especially water) that generates heat from within — hence the term endogenous diathermy, in contrast to the exogenous diathermy of traditional shortwave and microwave equipment.

The TECAR system was developed in Spain in the 1990s and introduced in Italy in the early 2000s, where it found particularly widespread use. Today it is present in almost all Italian physiotherapy clinics and is used in multiple fields: orthopedic, sports, rheumatological, and post-surgical.

The Capacitor Principle

The functioning of tecar therapy is based on the model of the parallel plate capacitor: the patient’s biological tissues act as a dielectric (material interposed between the two plates), the active electrode and the return plate act as the capacitor’s plates. When the device is activated, it generates an alternating high-frequency electric field that induces an oscillatory movement of the electrical charges present in the tissues. This movement generates molecular friction and, consequently, heat.

The peculiarity of this mechanism is that heat is generated inside the tissues themselves; it is not transferred from the outside inwards as happens with hot packs or infrared. This allows therapeutic temperatures to be reached even in deep tissues without overheating the skin surface.

How It Works: Capacitive vs. Resistive Mode

Tecar therapy is an electrotherapy technique using high-frequency electromagnetic fields to generate deep tissue heat for pain relief and tissue healing in musculoskeletal conditions. Tecar therapy differs from other forms of diathermy in its ability to work with two different modes: capacitive and resistive. The choice between the two depends on the target tissue and the pathology being treated.

Capacitive Mode

The capacitive electrode is coated with an insulating material (ceramic). This coating ensures that the energy concentrates in tissues with high water content, i.e., superficial soft tissues: muscles, skin, subcutaneous tissue, lymphatic and vascular system. Capacitive mode is ideal for treating muscle contractures, edema, venous and lymphatic stasis.

Resistive Mode

The resistive electrode is without an insulating coating (bare metal). In this case, the energy concentrates in tissues with greater resistance to current passage, i.e., less hydrated and denser tissues: tendons, ligaments, cartilage, bone tissue, and joint capsules. Resistive mode is the preferred choice for treating tendinopathies, capsulitis, ligamentous injuries, and joint pathologies.

Comparative Table: Capacitive vs. Resistive

In clinical practice, the two modes are often combined in the same session: starting with capacitive mode to prepare soft tissues and improve vascularization, and then proceeding with resistive mode to reach deep structures.

Mechanism of Action

Endogenous Diathermy

As anticipated, the fundamental mechanism of tecar therapy is endogenous diathermy: heat is generated within the tissues due to the oscillatory movement of charges. This differentiates it from external heat sources (packs, infrared, paraffin), where heat must penetrate from the surface to the depth, with significant dispersion.

Biological Effects

The controlled increase in temperature in deep tissues produces a cascade of biological effects:

• Vasodilation: The increase in temperature causes blood vessels to dilate, improving the supply of oxygen and nutrients to the treated area and facilitating the removal of catabolites (waste products of cellular metabolism).

• Increased cellular metabolism: Heat accelerates enzymatic reactions and cellular metabolism, promoting tissue repair processes. Cells involved in healing (fibroblasts, macrophages) work more efficiently.

• Anti-inflammatory effect: Improved circulation promotes the reabsorption of edema and inflammatory mediators, contributing to the resolution of the inflammatory process.

• Analgesic effect: The reduction of inflammation and edema, along with the direct action of heat on nerve endings, contributes to pain reduction. A “gate control” mechanism related to sensory stimulation is also hypothesized.

• Reduction of tissue stiffness: Heat increases the extensibility of collagen present in tendons, ligaments, and joint capsules, improving joint mobility. This is particularly relevant in the treatment of shoulder adhesive capsulitis.

• Muscle relaxation: Increased circulation and reduced muscle tone contribute to the relaxation of contracted muscles, making tecar therapy a valuable complement in the treatment of contractures.

Non-Thermal Effects

In addition to thermal effects, tecar therapy is hypothesized to produce athermic or sub-thermal effects, related to the movement of electrical charges at the cellular level: modification of membrane potential, stimulation of ion transport, and activation of cellular receptors. These effects, however, are still under study and not fully confirmed by scientific literature.

Indications: When Tecar Therapy is Needed

Tecar therapy finds application in a wide range of musculoskeletal conditions, both acute (after the hyperacute phase) and chronic. Below are the main indications, divided by type of affected tissue.

Muscle Pathologies

• Muscle contractures: Tecar therapy in capacitive mode is very effective in relaxing contracted muscles. It is one of the most used tools for the treatment of cervical, dorsal, and lumbar muscle contractures.
• Muscle strains: In the subacute phase of muscle strain, tecar therapy promotes the repair of micro-lesions of muscle fibers and the reabsorption of edema.
• Muscle tears: In grade I and II muscle tears, tecar therapy can be included in the rehabilitation program after the initial acute phase, to accelerate healing and prevent the formation of scar adhesions.

Tendon Pathologies

• Tendinopathies: Tecar therapy in resistive mode is widely used in the treatment of tendinopathies, such as epicondylitis (tennis elbow), Achilles tendinopathy, and rotator cuff tendinopathies.
• Tendinitis and tendinosis: The distinction between acute (tendinitis) and degenerative (tendinosis) forms is important for calibrating treatment intensity.
• Plantar fasciitis: Tecar therapy can contribute to the management of pain and inflammation of the plantar fascia.

Joint Pathologies

• Osteoarthritis: In forms of knee osteoarthritis and hip osteoarthritis, tecar therapy contributes to pain management and reduction of joint stiffness. It does not modify the degenerative cartilage process but can improve the patient’s quality of life.
• Adhesive capsulitis: In shoulder adhesive capsulitis (frozen shoulder), tecar therapy is used before joint mobilization to increase capsule extensibility.
• Sprains: In the subacute phase of knee sprain or ankle sprain, tecar therapy promotes edema reabsorption and recovery of mobility.

Spinal Pathologies

• Low back pain: In the treatment of back pain, tecar therapy is often associated with manual therapy to reduce pain and paravertebral muscle contracture.
• Dorsalgia: Dorsalgia responds well to tecar therapy, especially when there is a component of muscle contracture.
• Cervicobrachialgia: In cervicobrachialgia, tecar therapy can contribute to the management of cervical pain and arm radiation, in association with other techniques.

Post-Surgical Rehabilitation

Tecar therapy plays an important role in rehabilitation after orthopedic surgeries:

• Post-arthroscopy (knee, shoulder): for edema control and mobility recovery.
• Post-anterior cruciate ligament reconstruction: in the initial phases of rehabilitation, to reduce swelling and pain.
• Post-prosthesis (hip, knee): to promote functional recovery, with appropriate precautions regarding metallic components (see contraindications section).
• Post-rotator cuff surgery: to accelerate recovery and prevent stiffness.

Contraindications

Like all instrumental therapies, tecar therapy has some contraindications that the physical therapist must always check before starting treatment.

Absolute Contraindications

• Pacemakers and implantable defibrillators: The electromagnetic field generated by tecar therapy can interfere with the functioning of these devices. This is an absolute and non-negotiable contraindication.
• Tumors and neoplasms: Stimulation of vascularization and cellular metabolism could theoretically promote tumor growth. Tecar therapy is contraindicated in the presence of known or suspected tumors in the area to be treated.
• Deep vein thrombosis and thrombophlebitis: Vasodilation and increased blood flow could favor the detachment of a thrombus with potentially serious consequences (pulmonary embolism).
• Pregnancy: As a precautionary principle, tecar therapy is contraindicated during pregnancy, especially in the abdominal and pelvic regions.

Relative Contraindications

• Metal prostheses: The issue of metal prostheses is debated. The metals used in modern orthopedic prostheses (titanium, chrome-cobalt alloys) have high electrical conductivity, and the passage of high-frequency current could concentrate heat near the prosthesis. In clinical practice, many physiotherapists successfully treat patients with prostheses, using reduced power and carefully monitoring the patient’s sensations. However, caution and a case-by-case evaluation by the physical therapist are necessary.
• Osteosynthesis devices (plates, screws, intramedullary nails): The same considerations apply as for prostheses, with the need for caution and moderate power.
• Altered skin sensitivity: In patients with neuropathies or areas of hypoesthesia, the risk of burns is increased because the patient does not correctly perceive heat. In these cases, tecar therapy should be used with extreme caution or avoided.
• Areas with acute infections: Stimulation of vascularization could favor the spread of infection.
• Open wounds and skin lesions: Direct application of the electrode to damaged skin is contraindicated.

In case of doubts about contraindications, it is essential to consult your doctor before undergoing treatment.

How a Session Takes Place

Preparation

Before starting the treatment, the physical therapist performs a clinical evaluation to identify the area to be treated, choose the mode (capacitive, resistive, or both), set the power, and check for the absence of contraindications. The area to be treated is exposed, and a conductive cream (or gel) is applied to the skin to facilitate the electrode’s gliding and energy transmission.

Procedure

The treatment involves applying the active electrode to the affected area, while the return plate is positioned on the opposite side to close the circuit. The physical therapist moves the electrode over the skin with slow, circular movements, maintaining constant contact. Throughout the session, the operator adjusts the power based on the sensations reported by the patient.

Perceived Sensations

Tecar therapy is generally well tolerated and often described as pleasant. Typical sensations are:

• At low powers: a mild and diffuse warmth, very similar to a warm massage.
• At medium powers: more intense and deep warmth, perceived as an “internal warmth.”
• At high powers: marked warmth that should never become uncomfortable or painful. If the patient feels burning or discomfort, the physical therapist immediately reduces the power.

The treatment is not painful. In rare cases, in the presence of very inflamed tissues, slight discomfort may be felt in the initial phases, which tends to decrease during the session.

Duration and Number of Sessions

• Duration of a single session: generally between 20 and 30 minutes, varying based on the treated area and pathology.
• Number of sessions: a standard cycle includes 6 to 10 sessions, with a frequency of 2-3 times a week. The number may vary based on the patient’s response and the chronicity of the condition.
• Frequency: in acute phases, frequent sessions are preferred (even daily), in chronic phases, 2-3 times a week are generally sufficient.

No special precautions are needed after the session. Some patients report a feeling of well-being and muscle relaxation that persists for several hours.

Scientific Evidence: What the Literature Says

The Current State of Research

Tecar therapy is one of the most widespread tools in physiotherapeutic clinical practice, especially in Italy and Spain. However, it should be noted that the scientific evidence supporting it is moderate and research on this method presents some critical issues.

Several randomized controlled trials (RCTs) have investigated the effectiveness of tecar therapy in various musculoskeletal conditions. The results are encouraging in some areas, but the methodological quality of the studies is often limited by small sample sizes, lack of an adequate control group (sham/placebo), and short follow-up.

What the Evidence Suggests

• Low back pain: Some systematic reviews suggest that tecar therapy, in combination with therapeutic exercise, can produce a greater reduction in pain and functional improvement than exercise alone. The results are more robust for chronic low back pain.
• Tendinopathies: Moderate evidence supports the use of tecar therapy in tendinopathies, with improvements in pain and functionality. Again, the best results are obtained in combination with eccentric exercise.
• Knee osteoarthritis: Some studies show benefits in reducing pain and improving short-term functionality, but long-term results are less clear.
• Post-surgical rehabilitation: Preliminary evidence suggests a role in edema control and mobility recovery after orthopedic surgery.

Limitations of Research

• Many studies do not include a sham group (dummy treatment with the device off), making it difficult to separate the specific effect of tecar therapy from the placebo effect and the therapist’s manual contact.
• Tecar therapy is almost always used in combination with other techniques (manual therapy, exercise), making it difficult to isolate the specific contribution of the instrument.
• Most of the literature comes from Italy and Spain, with limited representation in Anglo-Saxon research.

Practical Considerations

Despite the limitations of research, tecar therapy remains a widely used and appreciated tool in clinical practice. The clinical experience of thousands of physiotherapists confirms its usefulness as an adjunct in the treatment of many musculoskeletal conditions. The advice is to rely on your physical therapist, who will be able to assess whether tecar therapy is indicated in the specific case and integrate it into a complete rehabilitation program that includes active exercise and manual therapy.

Tecar Therapy vs. Other Instrumental Therapies

Tecar therapy is not the only instrumental therapy available in physiotherapy. Below is a comparison with the main alternatives.

When to Prefer Tecar Therapy

Tecar therapy is particularly indicated when you want:

• An immediate decontracting and muscle-relaxing effect
• To treat a large area (tecar therapy allows covering large surfaces)
• To combine instrumental treatment with manual mobilization (the physical therapist can treat and mobilize simultaneously)
• A well-tolerated and non-painful treatment

When to Prefer Other Therapies

• Shockwave therapy: in case of tendon calcifications, resistant chronic plantar fasciitis, chronic insertional tendinopathies.
• Laser therapy: in case of skin lesions, superficial inflammation, when tecar therapy is contraindicated (pacemaker).
• Ultrasound: in case of superficial scar adhesions, small calcifications.

In clinical practice, these therapies are not necessarily in competition: they are often combined in integrated therapeutic protocols, based on the physical therapist’s assessment.

Indicative Costs

The costs of tecar therapy vary based on the geographical area, the facility (public, affiliated, or private), and the duration of the session. Below are some indicative guidelines for Italy.

Costs are purely indicative and can vary significantly. Tecar therapy is available in some public and affiliated facilities with the National Health Service, but availability varies from region to region. In many cases, treatment is provided privately.

It is advisable to request a quote from your physical therapist, clarifying the number of sessions planned and the duration of the treatment before starting the therapeutic cycle.

Frequently Asked Questions (FAQ)

Frequently Asked Questions

Is Tecar therapy painful?

Tecar therapy is generally not painful. Patients typically experience a pleasant sensation of warmth in the treated area, which can be adjusted by the physical therapist to ensure comfort. Any discomfort should be immediately communicated to the practitioner.

Does Tecar therapy have side effects?

When applied correctly by a trained professional, Tecar therapy is considered safe with minimal side effects. Potential minor and temporary effects might include slight redness or increased warmth in the treated area. Specific contraindications must always be considered to ensure patient safety.

Can Tecar therapy be done in the acute phase?

Yes, Tecar therapy can be applied in the acute phase of an injury. In such cases, it is often utilized with non-thermal settings to leverage its biological effects, such as reducing inflammation and promoting tissue repair, without generating significant heat.

How many Tecar therapy sessions are needed to see results?

The number of Tecar therapy sessions required varies significantly based on the individual’s condition, the severity of the pathology, and the patient’s response to treatment. A physical therapist will develop a personalized treatment plan and monitor progress to determine the optimal number of sessions.

Sources and Scientific References

1. Lupowitz LG et al. (2025). TECAR Therapy: A Clinical Commentary on its Evolution, Application, and Future in Rehabilitation. Int J Sports Phys Ther. 20:632-640. DOI | PubMed
2. Uzun Ö et al. (2025). Impact of TECAR therapy on pain and function in adhesive capsulitis: a randomized controlled trial. Lasers Med Sci. 40:231. DOI | PubMed
3. Nazari S et al. (2025). The effects of TECAR therapy on pain, range of motion, strength and subscale of HAGOS questionnaire in athletes with chronic adductor related groin pain: a randomized controlled trial. BMC Musculoskelet Disord. 26:76. DOI | PubMed
4. Boissevain I (2014). [Tecar therapy]. Tijdschr Diergeneeskd. 139:15. PubMed
5. Lippi L et al. (2024). Aesthetic Rehabilitation Medicine: Enhancing Wellbeing beyond Functional Recovery. Medicina (Kaunas). 60. DOI | PubMed