The influence of auditory stimuli (shots) and visual stimuli (SMS texting) on the parameters of the detection of the centre of gravity and the reaction of the ground forces in the static and dynamic test on the stabilometric platform – cohort studies

Introduction
Daily use of smartphones and personal listening devices (PLDs) generates destabilising conditions for the human body, especially in terms of balance. The multitude of external stimuli, such as sounds and texting, increases the risk of losing balance.

Aim of the research
The aim of the study was to assess the parameters of balance and reaction of substrate forces in a static and dynamic test under different conditions.

Material and methods
The study was conducted in a group of 52 people. The study included 3 attempts  30 s: I-in conditions of relative silence (RS), II-with the sound of a shot (S), and III-while texting (SMS), carried out in both static and dynamic conditions. The Zebris PDM-L stabilometric platform was used.

Results
Comparisons made for the free-standing test in the tests did not show significant relationships between the analysed variables (p > 0.05). The mean value of velocity of center of pressure (COP) when SMS texting in the dynamic test was 3.7 ±0.5 km/h, in the S test it was higher (4.4 ±0.5 km/h), and in the RS test it was 4.2 ±0.5 km/h (p < 0.001). The average number of steps per minute was the lowest in SMS test (104.5 ±7.9 steps/min), the highest in S test (109.6 ±7.3 steps/min) (p < 0.001). The average length of the COP path for both lower limbs was shortest in SMS test and longest in S test (p < 0.05).

Conclusions
The sound of a shot and texting did not affect the body’s balance under static conditions. In the dynamic test, the shot sound increased most of the parameters conditioning the gait, and texting resulted in greater concentration, slowing down the gait and stabilising the body.