FIR Technology: what it is, how it works, and why it's used in technical apparel

In recent years, FIR technology has become one of the most interesting innovations in the technical, sports and wellness clothing sector. In fact, more and more textile companies are using fibers enriched with mineral particles capable of interacting with body heat and returning it in the form of far infrared rays, also known as Far Infrared Rays (FIR).

This technology is the subject of growing interest by the scientific community and is being studied for its possible applications in comfort, sports recovery and microcirculation support. But what exactly are FIR rays?

How does this technology work in fabrics? And why is it used in new generation sportswear, leggings, bodysuits and technical clothing?

Let's find out in detail everything there is to know about FIR technology.

What is FIR technology?

The acronym FIR derives from the English expression Far Infrared Rays, translatable as "far infrared rays".

Infrared rays represent a form of natural energy belonging to the electromagnetic spectrum. They lie immediately beyond visible light and cannot be perceived by the human eye, but are commonly associated with heat transmission.

Within the infrared spectrum there are different bands. FIR rays occupy the most distant portion and are those most studied for applications related to well-being and the textile industry.

The peculiarity of FIR technology is that it does not produce energy independently, but uses the heat already emitted by the human body to activate a process of energy absorption and re-emission.

How does FIR technology work in fabrics?

To understand how FIR technology works it is necessary to start from a simple principle: the human body continuously emits thermal energy in the form of heat.

FIR fabrics contain mineral or bioceramic particles integrated directly into the fibres. These minerals have the ability to absorb part of the thermal energy produced by the body and re-emit it in the form of far infrared rays.

The process can be summarized in three phases:

1. Absorption of body heat

While using the garment, the fabric comes into contact with the body and intercepts part of the heat naturally produced by the skin.

2. Energy conversion

Mineral particles in the fiber convert the absorbed thermal energy into far infrared radiation.

3. Re-emission of FIR rays

The energy is returned to the body in the form of far infrared rays, giving rise to a continuous interaction between the tissue and body heat.

This system does not require batteries, electrical power or external energy sources. The only energy needed is that naturally produced by the body.

What does scientific research say about FIR technology?

In recent years, numerous studies have attempted to understand the biological effects of far infrared rays and tissues containing bioceramic particles.

Available research suggests that the interaction between FIR and the organism may influence some physiological processes, although the authors underline the need for further clinical investigations.

Among the most studied aspects we find:

• tissue oxygenation:
• peripheral microcirculation;
• muscle recovery;
• thermal comfort;
• well-being during physical activity;

A clinical study published on the scientific database PubMed Central observed an increase in superficial tissue oxygenation in subjects who wore fabrics containing FIR-emissive ceramic particles compared to traditional fabrics.

Other studies have highlighted possible improvements in parameters associated with microcirculation and peripheral perfusion.

FIR technology and microcirculation

When talking about FIR technology, one of the most frequently discussed topics concerns the relationship with microcirculation.

Microcirculation is made up of the network of small blood vessels that distribute oxygen and nutrients to the tissues.

Some research suggests that exposure to far infrared rays may help improve certain parameters associated with tissue oxygenation and microvascular function. 

For this reason FIR fabrics are often used in garments intended for:

• sporting activity; 
• post-workout recovery;
• daily use;
• prolonged well-being and comfort.

It is important to underline that FIR technology does not represent a medical treatment and should not be considered a cure for pathologies or circulatory problems.

FIR technology and sport

The sports sector is probably the one in which FIR technology has found the greatest diffusion.

Professional athletes and fitness enthusiasts are increasingly using garments made with fibers containing FIR-emitting mineral particles.

According to a systematic review published in the scientific journal PLOS ONE, some studies have observed possible benefits in post-exercise recovery and the perception of muscle fatigue.

Although evidence on direct athletic performance is still limited, recovery represents one of the most promising areas for the application of FIR technology.

For this reason many garments are worn not only during training, but also in the hours following physical activity.

Why is FIR technology used in technical clothing?

The growing interest in FIR fabrics is linked above all to their ability to integrate innovation and practicality.

In fact, unlike other technologies, the emissive minerals are incorporated directly into the fiber and do not require particular methods of use.

The main advantages associated with this technology are:

Continuous comfort

The technology works by exploiting the body's natural heat without requiring intervention from the user.

Technology integrated into the fiber

The mineral particles are an integral part of the fabric and do not constitute a surface treatment.

No external power

No batteries or electronics are needed.

Daily use

The garments can be worn during work, physical activity or leisure.

FIR and seamless fabrics: an innovative combination

Many garments that use FIR technology are made with seamless construction.

Seamless technology allows you to reduce the number of seams, improving comfort, adaptability and freedom of movement.

The union between FIR fabrics and seamless processing allows us to obtain garments characterized by:

• high elasticity;
• ergonomic fit;
• prolonged comfort;
• support during movement;
• excellent adaptability to body shapes.

For this reason, leggings, bodysuits, tops and technical shirts represent some of the most widespread applications of FIR technology.

 Who can use garments with FIR technology?

Versatility represents one of the greatest strengths of this textile innovation.

The FIR leaders are chosen by:

•  professional athletes;
• fitness enthusiasts;
• yoga and pilates practitioners;
• runner;
• people who spend many hours on their feet;
• those looking for maximum comfort during the day.

Use is extremely simple: simply wear the garment like a normal technical garment.

The future of FIR technology

Scientific publications in recent years show a growing interest in far infrared rays and their applications in the textile sector.

Ongoing research is delving into possible biological mechanisms associated with FIRs, including effects on vascular function, muscle recovery and overall well-being.

Although further clinical studies are needed to confirm many of the results observed so far, FIR technology currently represents one of the most promising innovations in the panorama of advanced technical fabrics.

Why choose F.I.R. clothing of FGM04?

FIR technology expresses its potential best when integrated into garments designed with attention to the quality of materials and fit. This is why FGM04 creates its seamless garments in Italy, combining textile innovation, comfort and attention to detail.

The fabrics are certified OEKO-TEX® Standard 100, one of the most internationally recognized textile certifications, which certifies the control of substances potentially harmful to human health.

Choosing F.I.R. clothing of FGM04 therefore means relying on Made in Italy technical garments that combine advanced technology, daily comfort and high quality standards.

Conclusion

FIR technology, acronym for Far Infrared Rays, uses special mineral particles integrated into textile fibers to absorb body heat and re-emit it in the form of far infrared rays.

The scientific evidence currently available suggests possible positive effects on tissue oxygenation, microcirculation and post-exercise recovery, although requiring further confirmation from clinical research.

Thanks to its practicality, its direct integration into fabrics and its ability to accompany the body during daily and sporting activity, FIR technology represents one of the most interesting innovations in the technical clothing and wellness sector today.

Scientific sources

1. PLOS ONE – Utilization of far infrared-emitting garments for optimizing performance and recovery in sport: a systematic review
   https://journals.plos.org/plosone/article?id=10.1371/journal.pone.0251282
2. PubMed Central (NIH) – Randomized Controlled Trial Comparing the Effects of Far-Infrared Emitting Ceramic Fabric Shirts on Transcutaneous PO₂
   https://www.ncbi.nlm.nih.gov/pmc/articles/PMC6205518/
3. Diabetes & Vascular Disease Research – Improved extremity tissue oxygenation with short-term exposure to textiles embedded with far infrared light emitting thermoactive particles
   https://journals.sagepub.com/doi/10.1177/14791641231170282
4. International Journal of Molecular Sciences – Therapeutic Potential of Infrared and Related Light Therapies
   https://www.mdpi.com/1422-0067/26/11/5134
5. Autex Research Journal – A Review of Textiles Reflecting FIR Produced by the Human Body
   https://www.degruyterbrill.com/document/doi/10.2478/aut-2022-0035/pdf
6. Lasers in Medical Science – Advances in far-infrared research: therapeutic mechanisms of disease treatment and applications
   https://link.springer.com/article/10.1007/s10103-024-03994-4
7. Scientific Reports (Nature) – Detecting the limits of the biological effects of far-infrared irradiation
   https://www.nature.com/articles/s41598-019-48187-0