COMPARATIVE ASSESSMENT OF THE AMPLITUDE-FREQUENCY CHARACTERISTICS OF CONTRALATERAL LOWER LIMB OSCILLATIONS IN YOUNG ATHLETES IN A VERTICAL STANCE

BACKGROUND: The development of instrumental methods for the functional diagnosis of adaptive changes in the body of children involved in sports is relevant.

AIM: To study the fluctuations of the contralateral lower extremities in young athletes in an upright stance in various frequency ranges.

MATERIALS AND METHODS: The analysis of amplitude-frequency characteristics in vertical standing was carried out in 18 children of both sexes aged 7 to 10 years, who regularly engage in athletics. Using two stabilometric platforms, the oscillation parameters of the left and right lower extremities were recorded in the low-frequency range (up to 1.0 Hz) for 20 seconds and in the high-frequency range (from 1.0 to 6.0 Hz) for 1 second. The magnitude of the angle of deviation of the oscillation axis α (deg) of the lower extremities from the median axis was determined. The values of the first maximum amplitudes and frequencies of vibrations of the left and right lower extremities were measured: a1, a2, a3 (mm) and f1, f2, f3 (Hz) – in the low frequency range, A1, A2, A3 (mm) and F1, F2, F3 (Hz) – in the high frequency range. The control group consisted of 18 children with normal daily physical activity.

RESULTS: Children-athletes revealed more optimal indicators of the amplitude-frequency characteristics of lower limb vibrations in the low-frequency and high-frequency ranges of the spectrum, compared with peers who do not engage in sports and lead a sedentary lifestyle. This was manifested in a frequency shift in the oscillations of the pressure centers of the contralateral lower extremities, in a decrease in all peak oscillation amplitudes in the low-frequency and high-frequency ranges, in lower asymmetry of oscillation amplitudes, in the stability of synchronization of oscillations of the lower extremities over the entire frequency spectrum.

CONCLUSIONS: The parameters of the amplitude-frequency characteristics of the contralateral lower extremities should be taken into account in the training process of primary school children in order to exclude the appearance of neuromuscular imbalance due to fatigue in order to prevent injury.