Tecar therapy (TT), also known as capacitive–resistive energy transfer (CRET), is a 448 kHz endogenous thermotherapy used to heat superficial and deep tissues through radiofrequency energy transmission. It is widely applied in sports rehabilitation to relieve pain, accelerate tissue repair, and improve muscle flexibility by increasing local blood flow. However, despite its clinical popularity, scientific data on its direct physiological effects—particularly on microcirculation and muscle perfusion—remain limited.
This study, conducted by researchers from the University of Applied Sciences and Arts of Southern Switzerland (SUPSI), Vrije Universiteit Brussel, and Thim International University of Applied Sciences (Landquart, Switzerland), aimed to quantitatively assess whether Tecar therapy, applied in its resistive (RES) and capacitive (CAP) modes, influences perfusion of the skin microcirculation (PSMC), intramuscular blood flow (IMBF), and skin temperature (ST).
Given that the two treatment modes act differently depending on tissue impedance—CAP targeting more superficial, water-rich tissues (e.g., muscle, lymphatic, connective tissue) and RES targeting deeper, denser tissues (e.g., fascia, tendon, capsule)—the researchers sought to determine the mode-specific circulatory responses under controlled laboratory conditions. By establishing objective perfusion data through laser speckle contrast imaging (LSCI) and power Doppler sonography, the study aimed to clarify the underlying mechanisms through which Tecar therapy enhances blood flow and supports the healing and recovery process in musculoskeletal tissues.
This was a randomized controlled pilot feasibility study carried out at the Rehabilitation Research Laboratory (2rLab), University of Applied Sciences and Arts of Southern Switzerland (SUPSI), in Manno. Ethical approval was obtained from the Canton Ticino Ethics Committee (Ref. 2018-00271/CE3327), and the study adhered to the Declaration of Helsinki.
A total of 10 healthy volunteers (6 men, 4 women; mean age ≈ 36 ± 11 years) were recruited from the university population. Inclusion required normal active range of motion and no pain or musculoskeletal pathology in the right upper extremity. Exclusion criteria included cardiovascular or neurological disorders, pacemaker, pregnancy, diabetes, metal implants, infection, or any prior upper-limb trauma or surgery.
Each participant attended three experimental sessions, each spaced one week apart to prevent carryover effects. The sessions corresponded to:
All treatments were administered using the T-Plus (Wintecare SA, Chiasso, Switzerland) device for 8 minutes on the volar aspect of the right forearm, standardized by anatomical tape markings to ensure identical probe placement. The inactive electrode was positioned under the right scapula, and conductive cream was applied to reduce impedance. In the RES mode, a stainless-steel probe without insulation was used to deliver energy into deeper, high-resistance tissues such as fascia and tendon; in the CAP mode, the probe was ceramic-coated to concentrate energy in superficial, water-rich tissues like muscle and skin. The PLAC condition alternated between the two probes while the device remained off, isolating mechanical probe contact effects.
Treatment intensity was calibrated through pilot testing to ensure tolerability while maintaining distinct power outputs between modalities—approximately 70 % for RES and 40 % for CAP (reduced to 35 % and 20 %, respectively, if heat sensation became excessive). Participants lay supine with the right arm fixed in a custom wooden frame to maintain position and muscle relaxation.
Measurements were taken before, immediately after (Post 1), 2 minutes after (Post 2), and 10 minutes after (Post 3) each application.
The following variables were recorded:
The experimental protocol included a 20-minute acclimatization period in a darkened, quiet room to stabilize baseline HR and blood pressure. Ambient temperature and humidity were monitored to ensure environmental consistency.
Statistical analysis was performed using SPSS v24. As data were not normally distributed (Shapiro–Wilk test), the Friedman test with Bonferroni correction was used for repeated measures, reporting median and interquartile ranges. Significant results were accepted at p < 0.05.
All ten participants completed the full experimental protocol without adverse effects, reporting the treatment as comfortable and tolerable. Room temperature and humidity remained stable throughout testing, confirming that observed changes were attributable to the Tecar applications rather than environmental variation.
Compared with placebo, both Tecar modes significantly altered skin microcirculation perfusion (p = 0.0001). The Resistive (RES) mode produced a notable 23 % median increase in perfusion, consistent with improved local circulation and capillary dilation. In contrast, the Capacitive (CAP) mode unexpectedly resulted in a slight 4 % decrease, possibly due to transient superficial vasoconstriction or sensor variability. The placebo condition (PLAC), involving probe movement without electrical current, showed a 24 % reduction in PSMC—likely caused by contact with a cold, unheated probe, emphasizing that the increases under RES were truly current-induced
01_Wintecare_JACM T-Plus Blood …
01_Wintecare_JACM T-Plus Blood …
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At the proximal forearm, RES mode induced a 2.0 % to 2.2 % increase in IMBF, reaching statistical significance at 10 minutes post-treatment (Post 3; p = 0.013). This delayed rise suggests sustained vasodilation in deeper muscle tissues even after treatment cessation. CAP mode showed small, inconsistent changes (≤0.8 %), while placebo demonstrated no effect. At the distal forearm, none of the modalities produced significant differences, likely reflecting lower vascular density in that region.
Only the Resistive mode significantly increased skin temperature (+2.8 °C; p = 0.0001), whereas CAP caused a smaller, non-significant +0.9 °C rise. The placebo application caused a 2.3 °C decrease, again due to the cooling effect of the steel probe and conductive paste in the absence of active current.
Neither heart rate (HR) nor mean arterial pressure (MAP) changed significantly in any session, confirming that Tecar therapy’s effects are localized rather than systemic.
Together, these findings demonstrate that Resistive Tecar therapy (448 kHz) selectively enhances deep muscular blood flow and skin perfusion, while Capacitive mode primarily influences more superficial layers with modest vascular effects. Importantly, these circulatory improvements occurred without systemic cardiovascular alterations, validating Tecar’s safety and precision in local hemodynamic modulation.
This randomized pilot study provides the first quantitative evidence that Tecar therapy (TT), delivered through the T-Plus by Wintecare, can significantly enhance local blood perfusion in both skin and muscle tissues—particularly when applied in the resistive (RES) mode. The RES application at 448 kHz produced meaningful, statistically significant increases in perfusion of the skin microcirculation (PSMC) and intramuscular blood flow (IMBF), along with a rise in skin temperature, while leaving systemic cardiovascular parameters (HR, MAP) unaffected. These results confirm that the physiological effects of TT are localized and not due to systemic circulation changes.
In contrast, the capacitive (CAP) mode showed smaller, transient changes, primarily limited to superficial layers. This pattern aligns with Tecar’s established mechanism of action—RES mode driving current deeper into dense, low-water tissues (fascia, tendon, capsule) and CAP mode acting on more hydrated, superficial soft tissues (skin, lymphatic, and muscular layers).
Clinically, the findings indicate that Resistive Tecar therapy is best suited for conditions where deep vascular activation and enhanced metabolic exchange are desired, such as chronic muscle stiffness, tendon remodeling, or delayed recovery, whereas Capacitive mode may be preferable in acute or superficial applications requiring gentler thermal influence.
Importantly, by using laser speckle contrast imaging (LSCI) and power Doppler ultrasonography, the study validated noninvasive imaging methods for quantifying Tecar-induced vascular changes. The authors emphasize that TT produces measurable circulatory and thermoregulatory responses in localized tissue regions, supporting its role as a targeted, endogenous thermotherapy capable of stimulating the body’s own recovery mechanisms without systemic side effects.
