Rhythmic acoustic stimulation and balance in a group of young athletes: a pilot study

Auditory stimulation represents a useful strategy to improve stability without interfering with daily activities in pathological and physiological conditions. However the characteristics of the stimulation are still debated. The aim of this work was to study the effect of different frequencies of auditory stimulation on postural stability in healthy young athletes, in order to examine their effect on reactive control and to verify whether there is a frequency that can best optimise their effect on balance, both under both open and closed eye conditions. A force platform was used to analyse balance and a metronome was employed to administer the auditory frequencies of 30, 60 and 120 bpm, in the open and closed-eye conditions. The results showed that, in the open eyes condition, the 60 and 120 bpm frequencies caused reduced area of the ellipse, indicating a better stability, while the lower one (30 bpm) did not induce any changes. In the case of visual deprivation (i.e. with closed eyes), our results showed reduced area of the ellipse during auditory stimulation at 30 and 60 bpm, but not at 120 bpm, confirming the improvement in stability, even in the case of a condition which involves greater postural instability. In conclusion, this paper underlined the beneficial effect of auditory stimulation on reactive balance control. Among the chosen frequencies, 60 and 120 bpm seem to have a greater beneficial effect on balance in an openeye condition, whereas in a closed-eye condition even the lowest frequency (30 bpm) is able to improve balance.