Infrared Laser and Classical Ballerinas' Feet

An aluminum gallium arsenide (AlGaAs) diode laser device (Twin laser, MMOptics, São Carlos, SP, Brazil) was used. The irradiation parameters were as follows: infrared laser (808 nm wavelength) with a spot area of 0.04 cm2, and an average optical power of 100 mW operated in a continuous mode during 1 minute per point, leading to an irradiance of 2,500 mW/cm2, energy of 6 J and fluence of 125 J/cm2 per point. The laser was applied on ballerina's feet twice a week during three months.