Studies & Research
Science transparently classified.
This library compiles selected publications on light and photobiomodulation, pulsating electromagnetic fields (PEMF), local vibration, and combinations of these technologies. Human, animal, and laboratory studies with positive, mixed, and negative results are considered.
Important Classification: Devices, wavelengths, field strengths, dosages, pulsations, application times, and target groups differ. The results are not automatically transferable to the CONNEE® Tri-Core System and do not constitute proof of efficacy for a specific CONNEE® product.
Light & Photobiomodulation
Organized by wavelength and then by human and animal research. Visible light, near-infrared light, ambient light, and local irradiation are not interchangeable.
Red Light and Near-Infrared · 660–850 nm
Red light primarily acts closer to the surface, while near-infrared can penetrate deeper depending on power, tissue, distance, and dose. Results are only valid for the specific protocol studied.
660 nm after wisdom tooth extraction2026 · randomized, double-blind, and placebo-controlled · 42 people
Differences in pain, mouth opening, and analgesic consumption were reported for the first few days. No clear differences were found for swelling, quality of life, or on the seventh day.
850 nm for mild sleep-related complaints2023 · randomized, double-blind, and placebo-controlled
Three energy doses were compared with placebo. Consistent changes in individual well-being and health values were observed only at the highest tested dose; dose and experimental setup are crucial for classification.
660 and 808 nm for knee osteoarthritisJankaew et al., 2023 · double-blind and randomized · 47 people
The 808 nm group showed greater improvements in knee extension strength. At 660 nm, the 30-second sit-to-stand test particularly improved; several other functional tests also improved in the sham group and did not clearly differ between groups.
850 nm for chronic knee osteoarthritis2013 · randomized and single-blind · 40 people
After eight applications, differences favoring the active laser group were reported for pain, knee function, and walking time. The small sample size and single-blinding limit the significance.
660 nm for dentin hypersensitivity2025 · randomized, controlled, and double-blind · 112 people
After seven and 30 days, pain scores after tactile and thermal stimulation were lower in the PBM group. No difference was found in analgesic consumption; only a dental context was investigated.
660 nm after perineal birth injuries2026 · randomized, controlled, and double-blind · 59 women
Compared to placebo, no clinical benefit was shown for pain or wound healing. Analgesic consumption was lower in the intervention group; however, the primary clinical outcome remained negative.
660 + 850 nm for temporomandibular joint disorders2026 · randomized, controlled, and partially blinded · 29 people
After six LED applications, a decrease in pain was reported in the treatment group. Most mobility values did not differ; additionally, the therapists were not fully blinded during execution and evaluation.
660 + 850 nm for sensory disturbances after mandible fracture2024 · randomized clinical trial · 42 people / 67 fractures
Combined LED application over six months was associated with faster regression of tactile and thermal sensitivity disturbances. Due to the combination, the contribution of individual wavelengths cannot be determined.
660 + 880 nm for exercise-induced muscle soreness2006 · randomized, double-blind, and controlled · 27 people
48 hours after unaccustomed exertion, lower pain scores were measured compared to sham or no treatment. No differences were found in arm circumference and range of motion.
660 + 850 nm in an eight-week running training programPeserico et al., 2019 · randomized and placebo-controlled · 30 men
Both groups improved their running performance. There was no statistically clear difference between PBM and placebo; individual effect sizes only provided hints of possible benefits.
850 nm in rugby players and muscle recovery2024 · randomized crossover study · 18 athletes
Application before, during, or after exercise did not change creatine kinase, lactate, and the tested performance values compared to control conditions.
Blue Light · Focus 450 nm
Blue light predominantly penetrates tissues superficially. Efficacy and safety highly depend on intensity, energy dose, pulsation, distance, and duration. Cell culture, whole-body illumination, local irradiation, and photodynamic therapy are not interchangeable.
450 nm LED in an experimental pain modelReuss et al., 2021 · blinded crossover study · 30 healthy adults
After artificially induced pain hypersensitivity on the forearm, locally applied 450 nm light reduced several pain and sensitivity values compared to red light and heat control. Healthy individuals were studied, not people with a pain condition.
450 nm, blood pressure and vascular functionStern et al., 2018 · randomized crossover study · 14 healthy men
A single 30-minute whole-body irradiation briefly influenced systolic blood pressure, vascular function, and various nitric oxide levels. The small, exclusively male sample and short-term measurement limit transferability.
415 and 450 nm for atopic dermatitisAD-Blue study, 2023 · randomized, double-blind, and sham-controlled · 87 people
For the 450 nm group, a change in self-reported itching was observed compared to sham. However, objective severity scores such as EASI, SCORAD, and IGA did not clearly improve.
400/450 nm for difficult-to-heal woundsJanowska et al., 2020 · prospective case series · 20 wounds
After four weeks, changes in wound area, wound bed, and pain were documented for many wounds. A control group was missing, and the wound causes varied.
Blue Light and Wound HealingPrado et al., 2023 · Scoping Review · 22 laboratory, animal, and clinical works
The works showed highly dose-dependent, sometimes contradictory reactions. Lower energy densities could stimulate certain processes, while higher doses inhibited proliferation, migration, and metabolism. A generally optimal application could not be determined.
450 nm on human skin and vascular cells2025 · In vitro and transcriptome study
In keratinocytes, fibroblasts, and endothelial cells, 4.5 J/cm² stimulated certain cellular processes; 18 J/cm² inhibited them. This biphasic laboratory reaction does not allow for a direct clinical statement.
450 nm component in optimized stable lightingMurphy et al., 2023 · investigation of circadian gene rhythm in horses
Changed stable lighting with additional blue light during the day and dim red light at night enhanced the rhythmicity of circadian genes in hair follicles. As the entire lighting system was changed, the effect cannot be attributed to 450 nm alone.
Safety aspect: 450 nm and skin pigmentationCampiche et al., 2020 · randomized, double-blind, and placebo-controlled · 33 women
Repeated high experimental exposure caused measurable pigment changes in skin types III and IV. It is not automatically comparable to therapeutic applications but emphasizes the importance of skin type and dosage.
Distinction: Studies with curcumin, aminolevulinic acid, or other photosensitizers describe photodynamic therapy. They do not prove the effect of blue light alone.
Green Light · 520–532 nm
Visually perceived green ambient light is not to be equated with LED or laser light locally shone onto the skin. Statements are only valid for the light source, wavelength, dose, and target group of the respective work.
Green Light and PainSystematic Review, 2026 · Human Studies
This review summarizes clinical studies on migraine, fibromyalgia, and other pain forms. The results are classified as interesting, but inconsistent depending on study design, comparison group, and condition.
525 nm ambient light for knee osteoarthritisMartin et al., 2026 · unilateral crossover study · 19 people
After daily exposure, lower self-reported pain, function, and WOMAC scores were observed. Small sample size and non-randomized treatment order limit the significance.
```525 nm ambient light for migrainesMartin et al., 2021 · unilateral crossover study · 29 individuals
Fewer headache days and improvements in several self-reported quality of life scores were observed after a white light phase followed by green light exposure. The fixed sequence limits the validity.
525 nm ambient light for fibromyalgiaMartin et al., 2021 · unilateral crossover study · 21 individuals
During the green light phase, participants reported lower average pain and better quality of life. This was a preliminary investigation without randomized order.
532 nm laser for body contouringSuarez et al., 2014 · randomized, double-blind, and sham-controlled · 67 individuals
After six applications, larger short-term changes in combined measured circumferences of the waist, hips, and thighs were reported. Circumference values were measured, not reliable permanent loss of fat mass or body weight.
532 nm laser in obese individualsRoche et al., 2017 · randomized, double-blind, and sham-controlled · 53 individuals
After four weeks, greater changes in combined body circumferences were reported compared to sham. The focus was on circumference measurements; one author was affiliated with the device manufacturer.
Combined 520 and 405 nm laser for submental fatWilliams et al., 2025 · prospective and open-label · 31 individuals
After eight combined applications, a reduction in submental skin fold thickness was reported, with BMI remaining unchanged. There was no sham group; both wavelengths were used simultaneously and two authors worked for the device manufacturer.
520 nm LED and wound healing in fishLee et al., 2023 · controlled in vivo and in vitro study
In olive flounders, a specific intensity accelerated wound healing. A higher intensity showed stressful physiological effects. The animal model is not transferable to humans, horses, dogs, or CONNEE® products.
Conclusion on fat reduction: No robust independent clinical study demonstrating fat or weight reduction by 520 nm light alone has been identified. Results for 532 nm or combined wavelengths cannot be used as product-specific evidence for CONNEE®.
Veterinary Medicine · Light and Photobiomodulation
Animal studies are particularly interesting for CONNEE® target groups. Nevertheless, devices, fur, skin pigmentation, anatomical depth, and treatment protocols vary considerably.
Dog: Photobiomodulation for hip osteoarthritisAlves et al., 2022 · randomized and double-blind · 20 dogs
The treated group showed improvements in several pain and functional scores. A therapeutic Class IV laser with different parameters than the CONNEE® system was investigated.
Dog: Photobiomodulation for elbow osteoarthritisLooney et al., 2018 · randomized, blinded, and placebo-controlled · 20 dogs
In the PBM group, improvements in lameness and pain, as well as reduced NSAID requirements, were reported. The sample size was small.
Dog: 830 nm or 660/875/905 nm for chronic woundsHoisang et al., 2021 · randomized controlled trial · 21 dogs
Both PBM groups showed a greater wound area reduction than the control group at times. The multi-wavelength group does not allow conclusions about the contribution of 660 nm alone; 830 nm is not identical to 850 nm.
Dog: Multi-wavelength PBM after cruciate ligament surgery2018 · randomized and placebo-controlled · 95 dogs
The protocol with 660, 800, 905, and 970 nm showed an advantage in a gait score rated by owners, but no convincing advantage in bone healing or other clinical measures.
Horse: 635 nm for experimental skin woundsJann et al., 2012 · controlled wound model · 8 horses
Treated wounds healed faster than control wounds in this model. 635 nm is in the red range, but not identical to 660 nm; the small experimental study is not product-specific evidence.
Horse: 637 and 956 nm for experimental skin woundsPetersen et al., 2020 · randomized and blinded · 8 horses
In this experimental setup, no clinically relevant positive effect on wound healing was observed. The study is important because it highlights limitations and differing results.
Pulsed Electromagnetic Fields · PEMF
PEMF studies use very different frequencies, field strengths, waveforms, and application times. Results from one protocol cannot be generally applied to other devices.
Dog: PEMF for hip osteoarthritisKühl et al., 2025 · randomized clinical trial · 20 dogs
The PEMF group showed improvements in validated pain questionnaires. No significant differences were found in range of motion and thigh circumference; the sample size was small.
Dog: single PEMF application for hip osteoarthritis2024 · randomized, double-blind, and placebo-controlled · 8 dogs
After a single application, no demonstrable improvement in owner-rated pain or spatiotemporal gait parameters was observed.
Human: PEMF for knee osteoarthritisBagnato et al., 2016 · randomized, double-blind, and placebo-controlled · 60 individuals
After one month, differences in pain and WOMAC scores were reported compared to placebo. A specific portable device with its own protocol was investigated.
Local Vibration & Neuroathletic Training
“Neuroathletic training” is not a uniformly defined scientific term. Relevant research refers, among other things, to proprioception, sensorimotor integration, neuromuscular control, and motor learning. Only local or focal applications are listed here – no vibration plates.
Focal vibration for sprint, jump, and muscle strengthCanet-Vintró et al., 2024 · double-blind and randomized · 70 amateur athletes
Focal vibration was combined with active muscle contractions. Differences in favor of the intervention were reported for 30-meter sprint and countermovement jump; quadriceps strength also improved within the intervention group.
Local quadriceps vibration before single-leg landingLi et al., 2026 · randomized crossover study · 24 healthy men
In an unfatigued state, acute application altered several biomechanical measures. After combined physical and cognitive fatigue, these kinematic effects were not observed.
Focal vibration and arm movement qualityAprile et al., 2016 · three-group study · 48 individuals
100 Hz, 200 Hz, and a control group were compared. Ten days later, differences in repetitions and movement smoothness were observed with 200 Hz in a robot-assisted targeting task.
Focal muscle vibration and sensorimotor integrationManzo et al., 2023 · experimental neurophysiological study
The processing of tactile stimuli during movement was only influenced when vibration was applied to the involved muscle. The study shows a short-term modulation, not automatically a performance improvement.
Motor conditioning through focal muscle vibrationFattorini et al., 2021 · systematic review · 12 studies
The included works reported changes mainly in strength and performance. Applications, frequencies, and durations differed significantly; a generally applicable protocol recommendation is not possible.
Focal vibration and motor cortex activityKolbaşı et al., 2022 · systematic review · 18 studies / 264 individuals
Depending on the study, increased, decreased, or unchanged activity in the motor or somatosensory cortex was observed. The contradictory results highlight the importance of muscle, frequency, amplitude, and duration.
Local vibration, motor control, and learningTseng et al., 2025 · Scoping Review
Local vibration to the muscle or tendon is described as a proprioceptive stimulus that can influence motor control and learning processes. The most sensible use is classified as a supplement to active movement or rehabilitation training.
Classification for CONNEE®: Contact point, frequency, amplitude, duration, and accompanying exercises differ. The results are not automatically transferable to the CONNEE® Tri-Core System.
Combinations of Technologies
Studies on two-way combinations require particularly careful classification: they do not show which component caused an observed effect. Furthermore, a two-way combination is not proof of the complete Tri-Core system.
Photobiomodulation plus PEMF for androgenetic alopeciaChoi & Park, 2023 · randomized, double-blind and sham-controlled · 80 individuals
Positive results were reported in this narrowly defined application area. The device, treatment goal, and protocol differ fundamentally from the CONNEE® System.
Dog: PBM and PEMF in addition to Bedinvetmab2026 · prospective, randomized and open · 30 dogs with hip osteoarthritis
Bedinvetmab alone was compared with Bedinvetmab plus twice-weekly PBM and PEMF. From day 30, higher pressure pain thresholds were reported in the combination group. The contributions of the two physical procedures and a possible synergy cannot be separated.
Magneto-LED therapy for venous leg ulcers2024 · preliminary clinical comparative study · 81 individuals
The combination was compared with magnet stimulation alone in addition to standard care. After 40 applications, the wound area decreased more in the combination group; the study was neither sham-controlled nor blinded.
Magneto-LED therapy for hip osteoarthritis2019 · comparative observational study · 30 men
Both groups reported less pain; only in the group with magnet stimulation and red LED light did analgesic consumption decrease. The small study was not sham-controlled.
Magneto-LED therapy for back pain2011 · comparative study · 66 individuals
Magneto-LED therapy, magnet stimulation, and TENS were compared. The authors reported a pain-relieving effect of the combination of infrared LED and magnet stimulation; the older publication contains only limited methodological information.
Red LED light plus low-frequency magnetic field2024 · In-vitro study with human keratinocytes
630 nm LED light and a low-frequency magnetic field were investigated simultaneously. Observed changes in cell activity and inflammation markers do not allow for clinical statements for humans or animals.
Photobiomodulation plus static magnetic fieldRibeiro et al., 2023 · randomized and placebo-controlled · 90 individuals
Differences in several pain measures were reported for fibromyalgia. However, a static magnetic field is not the same as PEMF and should not be equated with it.
The exact combination of light, PEMF, and vibration:
For the exact combination of all three technologies in the parameters of the CONNEE® Tri-Core System, no direct clinical study was identified in the reviewed literature. Individual studies and two-way combinations do not replace product-specific evidence.
Technologies at a glance.
Delve into the technical foundations behind the topics covered in the study library.
How to read the studies correctly.
- Results initially apply only to the studied population and the protocol used.
- Wavelength alone is not enough: power, energy dose, pulsing, distance, and duration influence the application.
- Small pilot studies provide indications, but no conclusive evidence.
- Neutral and negative results are also part of a transparent scientific classification.
Medical Notice: This collection is for general information purposes only. It does not replace medical or veterinary diagnosis, advice, or treatment. For health concerns, please consult qualified medical or veterinary professionals.
Literature selection reviewed: September 2026 · The library will be updated with relevant new publications.