In our living bodies, the most important part of supplying the cells and removing waste products takes place via the micro vessels, which plays a vital role in health. The process is called microcirculation since segment of the blood circulation system locates in the microvascular region lying between the arterioles and venules.1 At this point, the primary function of the circulating blood in vessels is to transport oxygen and precious nutrients, and to remove carbon dioxide and other waste materials.2
Clinical studies have already shown that impaired microcirculation causes various types of diseases and symptoms such as Raynaud's syndrome3, cardiovascular health problems4 and so forth. They could be in/directly associated with disorders in the microcirculation system. In other words, these diseases would be potentially treated by enhancing the microcirculation system in a living body. This means, curing the microcirculation is vital in the treatment of essential health problems. Therefore, specific treatment techniques are needed to enhance the blood microcirculation for targeted regions of the body via elevating/regulating local tissue temperature and leading to dilation of blood vessels.
Infrared (IR) is a sort of electromagnetic radiation and its wavelengths are indicated between 0.78 μm and 1000 μm in electromagnetic spectrum. IR is divided into diﬀerent bands. They are defined as near-infrared (N-IR, 0.78–3.0 μm), mid-infrared (M-IR, 3.0–50.0 μm) and far-infrared (F-IR, 50.0–1000.0 μm) according to the ISO standard5. The classification of the International Commission on Illumination (CIE) has three sub-divisions for the IR radiation. CIE describes and recommends the wavelength range of the FIR from 3.0 μm to 1000 μm. There is still no clear consensus and universal standard in the scientific community for determination, measurement and evaluation of F-IR properties.
Far infrared (FIR) therapy appears as an interesting technique to improve the microcirculation system of the living body in a novel way. The FIR is a sub-division of the electromagnetic spectrum that has been investigated for its biological effects extensively. Especially in the 4–14 µm range, it is promising to stimulate cells and tissues growth in both in vitro and in vivo studies.6 The FIR wavelengths have relatively high penetrability up to 1.5 inches beneath the skin deep into tissue and induce a higher skin blood ﬂow in most biological materials. In this point, FIR penetrates through the skin into subcutaneous tissue that induces the generation of heat energy through its resonance effects. That stimulates intramolecular micro-vibrations to invigorate cellular activities through expanding capillaries and increase the circulation of nutrient-rich, oxygenated blood, thus improving overall metabolism.6 FIR also regenerates tissues and activates the immune system and enhances the removal of cellular waste materials.7 Consequentially, that therapy exhibits numerous benefits to enhance the health of patients with cardiovascular diseases (CVD)8, regenerating skin and muscle/wound tissues9, relaxation of muscles10, relieving of pains11 and so forth.
The FIR expedites the generation of nitric mono-oxide (NO) in the blood vessels that is called Endothelial NOS (eNOS) is an enzyme that in humans is encoded by the NOS3 gene located in the 7q35-7q36 region of chromosome 7.12 This enzyme is known as one of three isoforms that synthesize nitric oxide (NO), a small gaseous and lipophilic molecule that participates in several biological processes.13,14 NO plays important role to regulate blood circulation and pressure and cleaning clog in blood vessels.15 The Nobel Prize in Physiology or Medicine in 1998 was awarded for discovery of NO as a signalling molecule in the cardiovascular system.
FIR therapy can be performed by different sources i.e. FIR saunas, FIR emitting medical devices and FIR emitting lamps. Besides, these FIR lamps are utilized in some types of FIR saunas. These FIR theraphies are beneficial but costly. This types of treatment techniques require extra time to be arranged, that is another issue to be taken into consideration. Besides, there has been reported that FIR saunas may cause eye irritation that would be an adverse effect for this treatment technique.16
FIR-textiles offer a unique way to deliver this therapy for continuous use. These functional textile structures in various forms e.g. fibers, fabrics, composites, films have significant benefits for several types of diseases, symptoms and problems. FIR functionality can be incorporated into textile products in a variety of ways. For instance, FIR gloves were reported to help treat arthritis of the hands and Raynaud’s syndrome.17 FIR belts were found to to manage the discomfort of primary dysmenorrhea in female patients 18 and reduce menstrual pain.19 FIR socks were shown to have a beneficial impact on chronic foot pain resulting from diabetic neuropathy or other disorders.20 Especially elderly and paralyzed people are not able to move their body parts enough. So, blood circulation of these people is crucial. Hence, FIR-textiles can give promote effects of these people due to microcirculation improvement of FIR-emitting particles.
Our primary target is to develop functionalized cellulosic fibres which have far-infrared absorbing and emitting properties at LCPP at University of Maribor and to spin them into yarn by Predilnica Litia d.o.o company in Slovenia. Thereafter, we plan that various FIR fabric protoytpes can be produced from these functionalized yarns.
1. FAHICP. Microcirculation - The importance of tiny vessels for healthy blood circulation. (2018).
2. Dyer, J. Infrared functional textiles. in Functional Textiles for Improved Performance, Protection and Health 184–197 (Elsevier, 2011).
3. Csiki, Z. et al. Microcirculation of the fingers in Raynaud’s syndrome: (99m)Tc-DTPA imaging. Nukl. Nucl. Med. 44, 2932 (2005).
4. Tibiriçá, E. V., Lorenzo, A. de & Oliveira, G. M. M. de. Microcirculation and Cardiovascular Diseases. Arq. Bras. Cardiol. (2018). doi:10.5935/abc.20180149
5. ISO 20473:2007 Optics and photonics – Spectral bands, by ISO/TC 172 Optics and photonics, 3 pages, 2015
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7. Lin, C.-C. et al. Far-Infrared Therapy: A Novel Treatment to Improve Access Blood Flow and Unassisted Patency of Arteriovenous Fistula in Hemodialysis Patients. J. Am. Soc. Nephrol. 18, 985–992 (2007).
8. Shui, S., Wang, X., Chiang, J. Y. & Zheng, L. Far-infrared therapy for cardiovascular, autoimmune, and other chronic health problems: A systematic review. Exp. Biol. Med. Maywood NJ 240, 1257–1265 (2015).
9. Lin, Y.-H. & Li, T.-S. The Application of Far-Infrared in the Treatment of Wound Healing: A Short Evidence-Based Analysis. J. Evid.-Based Complement. Altern. Med. 22, 186–188 (2017).
10. Mero, A., Tornberg, J., Mäntykoski, M. & Puurtinen, R. Effects of far-infrared sauna bathing on recovery from strength and endurance training sessions in men. SpringerPlus 4, 321 (2015).
11. Lai, Y.-T. et al. Far-infrared ray patches relieve pain and improve skin sensitivity in myofascial pain syndrome: A double-blind randomized controlled study. Complement. Ther. Med. 35, 127–132 (2017).
12. Marsden, P.A., Schappert, K.T., Chen, H.S., Flowers, M., Sundell, C.L., Wilcox, J.N., Lamas, S., Michel, T., 1992. Molecular cloning and characterization of human endothelial nitric oxide synthase. FEBS Lett. 307, 287–293. https://doi.org/10.1016/0014-5793(92)80697-F
13. Cockcroft, J., 2005. Exploring Vascular Benefits of Endothelium-Derived Nitric Oxide. Am. J. Hypertens. 18, 177–183. https://doi.org/10.1016/j.amjhyper.2005.09.001
14. Villanueva, C., Giulivi, C., 2010. Subcellular and cellular locations of nitric oxide synthase isoforms as determinants of health and disease. Free Radic. Biol. Med. 49, 307–316. https://doi.org/10.1016/j.freeradbiomed.2010.04.004
15. Leung, T.-K., Lin, Y.-S., Chen, Y.-C., Shang, H.-F., Lee, Y.-H., Su, C.-H., Liao, H.-C., Chang, T.-M., 2009. Immunomodulatory effects of far-infrared ray irradiation via increasing calmodulin and nitric oxide production in raw 264.7 macrophages, Biomed. Eng. Appl. Basis Commun. 21, 317–323. https://doi.org/10.4015/S101623720900140
16. ICNIRP statement on far infrared radiation exposure, International Commission on Non-Ionizing Radiation Protection. Health Phys. 91, 630–645 (2006).
17. Ko, G. D. & Berbrayer, D. Effect of ceramic-impregnated ‘thermoflow’ gloves on patients with Raynaud’s syndrome: randomized, placebo-controlled study. Altern. Med. Rev. J. Clin. Ther. 7, 328–335 (2002).
18. Ke, Y.-M. et al. Effects of Somatothermal Far-Infrared Ray on Primary Dysmenorrhea: A Pilot Study. Evid. Based Complement. Alternat. Med. 2012, 1–8 (2012).
19. Lee, C. H. et al. A multicenter, randomized, double-blind, placebo-controlled trial evaluating the efficacy and safety of a far infrared-emitting sericite belt in patients with primary dysmenorrhea. Complement. Ther. Med. 19, 187–193 (2011).
20. York, R. M. & Gordon, I. L. Effect of optically modified polyethylene terephthalate fiber socks on chronic foot pain. BMC Complement. Altern. Med. 9, (2009).
ESR 11 - Litija