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A double dose of stimulation

Physical exercise, associated with LEDs, improves the health of post-menopausal women

Eduardo CesarThe use of light for treating various illnesses and also in beauty treatment is a well-established practice in dermatology consultation rooms and clinics. A new approach, which associates infrared radiation from light-emitting diodes (LEDs) with physical exercise on an ergometric treadmill, showed encouraging results in a study done on post-menopausal women. It contributed to improving various aspects related to aging, such as osteoporosis, muscular function, lipid profile, aerobic capacity and even beauty, allied with a visible reduction in cellulite and an improvement in the external aspect of the skin. The initial study was conducted for a year by physical education teacher, Fernanda Rossi Paolillo, during her PhD project in biotechnology, which she defended at the Federal University of São Carlos (UFSCar), supervised by Professors Vanderlei Bagnato and Cristina Kurachi, from the São Carlos Institute of Physics (IFSC) at the University of São Paulo (USP). Bagnato is the coordinator of the São Carlos Research Center in Optics and Photonics (CePOF), one of the Research, Innovation and Dissemination Centers (Cepid) funded by FAPESP.

“The reason for choosing infrared LED combined with the treadmill is that exercise raises the metabolic level”, says Bagnato, who developed the equipment used in the research. Comprising two aluminum plates, each with 2000 LEDs, it was conceived for the purpose of irradiating a body area that includes the buttocks and the quadriceps, which are used in the support and balance phase of the act of walking. “In this area there is a greater incidence of osteoporosis, mainly in the femur, as well as localized fat and cellulite”, says Fernanda. The thousands of diodes are arranged in a curve and the height can be regulated. The research had the support of a multidisciplinary team, comprising physicists, engineers, physiotherapists, physical education teachers, doctors and other health professionals, in addition to the Technology Support Laboratory(LAT) of the Optics Group at USP and  the Physiotherapy Department at UFSCar.

Infrared is a radiation in the invisible part of the electromagnetic spectrum, close to red in the visible light spectrum. Although it is not perceived as light by man, it can be felt as warmth by specialist nerve endings in the skin, known as thermoreceptors. Infrared radiation of 850 nanometers was chosen for the experiment because it penetrates the skin better than infrared light. “When it enters the skin it triggers a series of chemical reactions”, says Fernanda. “Infrared accelerates the transportation of electrons in the mitochondria and increases the production of adenosine triphosphate(ATP), a nucleoside responsible for storing energy coming from cellular respiration in our organism, which is used for immediate consumption in various biological processes”, she reports.

Infrared also helps regenerate tissue, like the skin, muscles, bones and nerves. In other words, phototherapy improves cell activation and accelerates the organism’s metabolic processes, resulting in benefits, particularly when applied during physical exercise on an ergometric treadmill. “Exercises done on the treadmill increase aerobic capacity and use the metabolism of fat, in addition to producing osteomuscular benefits”, says Fernanda. “In combining exercise and infrared radiation with lighting up the largest possible muscle mass, we want to prolong the physical conditioning of people who have become elderly”, emphasizes Bagnato.

Metabolic activity
The research was conducted on 30 women, with ages varying between 50 and 60 in a post-menopausal phase, characterized by the absence of menstruation for more than a year, and who had not had hormone replacement therapy. Women who had neurological, metabolic, inflammatory and endocrine problems and diseases like cancer and heart problems were excluded. The volunteers were told not to change their eating habits during the study. The group was divided into three, each with ten women. The first group used the treadmill and received infrared radiation, the second just did exercise and the third did nothing. They were accompanied for a whole year. During this period, the two first groups exercised on the treadmill, with and without infrared, twice a week for 45 minutes. “A year is the minimum time for assessing the behavior of bone mass”, says Fernanda. The distance between the device and the skin of the volunteers was 15 centimeters, all wore bikinis to absorb the infrared light directly and used goggles.

With bone densitometry examinations carried out at the beginning and end of the training program there was found to be a reduction in bone loss in the femurs of women who had associated exercise with infrared. The group that only used the treadmill, on the other hand, lost a significant amount of bone mass during the study period. “The improvement in the bone mass indicates that when mechanical stimulation is associated with the LEDs, muscle performance and bone formation improve because of the piezoelectric effect”, says Fernanda. Muscles function as a mechanical charge that is transformed into an electrical signal and causes osteogenic (bone formation) stimulation.

According to the researcher, a thermographic assessment indicated an increase in metabolic activity. In the thermal images of the body it is possible to see colored marks that indicate the increase in skin temperature and vasodilation in the women in the group that exercised with the LEDs. “This shows there was an improvement in blood circulation and an increase in oxygen in the exercised muscle, as well as the transport and elimination of metabolic substances, like lactic acid, which cause fatigue and muscle pain”. The increase in circulation and oxygen supply promoted tissue regeneration, particularly in the skin, thereby contributing to a reduction in cellulite and an improvement in the external “orange peel” aspect of the skin.

“We didn’t see a loss in the percentage of fat, but there was a reduction in the body circumference, mainly in the thigh and hip area, which is why we believe that infrared works like lymphatic drainage”, says Fernanda. Another important aspect emphasized by the researcher is the increase in collagen synthesis, with a visible improvement in the aspect of the skin. But this result was only obtained when technology was allied to exercise. “Infrared has been widely used in cosmetic dermatology for stimulating collagen”, says Professor Solange Teixeira, from the Department of Dermatology at the Federal University of São Paulo (Unifesp). Cosmetic dermatology is an area of dermatology that focuses on facial and body beauty treatment. “Infrared is a wavelength that penetrates the skin until it reaches the dermis, where it heats this subcutaneous tissue that is responsible for the resistance and elasticity of the skin”, says Solange. Collagen on the other hand is a protein and when it is heated to a certain temperature the fiber contracts, making the skin stretch, the so-called lifting effect.

CEPOF SÃO CARLOSImage shows the position of the LED plates alongside the treadmillCEPOF SÃO CARLOS

Effects boosted
There are some commercial devices for combating cellulite with infrared, but they work with suction and radiofrequency – emitting a radio wave that heats the tissue that supports the skin. “When used jointly with mechanical massage they boost the treatment to reduce skin flaccidity”, says Solange.

Muscular and aerobic performance were also tested in the IFSC’s research. “There was an increase in muscle power and a reduction in fatigue in women who exercised with infrared”, Fernanda emphasizes. The explanation is that infrared radiation boosts the effects of the exercise. To evaluate strength, an isokinetic dynamometer was used, a standard device for measuring muscle strength and for analyzing cardiovascular capacity. The volunteers underwent ergometric tests which found that they were exercising in a highly intense way and with less cardiovascular effort. “This group exercised more, for longer, at a higher speed and with a lower heart beat than those who only exercised”.

Another important aspect observed in the group of women who exercised while receiving infrared was the improvement in the lipid profile, which allows the risk factor for coronary disease to be assessed. In other words, the higher the level of LDL (low density lipoprotein) and the lower the HDL (high density lipoprotein), the greater the risk of cardiovascular problems. “In the LED group there was a reduction in overall cholesterol and of LDL cholesterol”, Fernanda relates. With regard to cholesterol, various factors contribute to its reduction, like food and exercise itself. “Even so, in the LED group there was a 20% reduction in overall cholesterol and LDL cholesterol when compared to the group that merely exercised”.

From the results they obtained the researchers suggest that the dose of infrared should be around 100 joules per square centimeter (100 J/cm2), the same as used in the research. “The dose of light is like a dose of medication; it has to be adjusted to the objective”, says Fernanda. The public that may benefit from the new therapeutic proposal is not restricted to women over 50. “The benefits are clear and we can innovate when handling athletes with this technology”, says Bagnato. The research group had already tested the light before and after exercise in some types of therapy. “But the research proved that using light during exercise produces better results”. A second prototype of the equipment has already been developed and is being installed in some rehabilitation clinics and fitness centers, including sports, rehabilitation and beauty clinics, in order to be able to expand the concept and test the benefits more widely.

CEPOF SÃO CARLOS Thermal images of the body: increase in temperature and vasodilationCEPOF SÃO CARLOS

Economic points of light
Eclectic LEDs and their advantages and disadvantages

The light emitting diode, better known by its acronym LED, is an electronic semiconductor component that is similar to computer chips. It has the property of transforming electricity into light in a way that is different from conventional lamps, which use metallic filaments, ultraviolet radiation and other methods. LEDs, in addition to substituting lamps, are used in producing displays, in televisions and cell phones, for example, and also offer the benefit of consuming little energy. They are also employed in a series of pieces of equipment used in medicine and dentistry for various types of therapeutic applications.

There are marked differences between light emitting diodes and lasers, although both technologies can be used for the same applications. The laser uses the stimulated emission of radiation, which unleashes a series of actions between the light particles, resulting in all of them moving in the same direction. When this occurs it produces a laser beam, which is called coherent because its particles all have the same behavior. The light from the laser is concentrated, monochromatic (same electromagnetic wavelength, with little heat dispersion) and highly collimated (it is a beam of practically parallel waves). The light that originates from LEDs, on the other hand, is not coherent or collimated and acts in a wider wavelength band. The advantages of LEDs over lasers are their low cost and the possibility of irradiating a large body area, as well as the possibility of configuring them to produce multiple wavelengths.

The project
Effects of LED (850 nm) light associated with treatment on an ergometric treadmill in post-menopausal women (nº 1998/14270-8); Modality Research, Innovation and Dissemination Centers (Cepid); Coordinator Vanderlei Bagnato – CePOF/USP; Investment R$ 1 million a year for CePOF (FAPESP)

Scientific articles
PAOLILLO, F.R. et al. Effects of infrared-LED illumination applied during high-intensity treadmill training in postmenopausal women. Photomedicine and Laser Surgery. Online issue, Jul. 2011.
PAOLILLO, F.R. et al. New treatment of cellulite with infrared-LED illumination applied during high-intensity treadmill training. Journal of Cosmetic and Laser Therapy. v. 13, p. 166-71. Aug. 2011.