Relationship between static and dynamic balance in 4-to-5-year-old preschoolers: a cross-sectional study.

BACKGROUND: Balance is crucial for physical development in preschool children. Exploring the relationship between different types of balance can help understand early physical development in children. Currently, research is mostly focused on the relationship between different types of balance in the adult population and lacks exploration of the preschool population. The aim of this study explored the relationship between static and dynamic balance in preschool children aged 4 to 5 years. METHODS: A total of 128 preschool children between the ages of 4 to 5 years were selected. The following tests were conducted as they wore inertial sensors detecting their centers of mass (COM): T1, standing with eyes open; T2, standing with eyes closed; T3, standing with eyes open on foam; T4, standing with eyes closed on foam; and T5, walking on the balance beam. Static balance was measured by the angular velocity modulus (ω-T1-ω-T4) of the shaking COM, as well as the pitch angle (θ-T1-θ-T4) and roll angle (φ-T1-φ-T4) indicators in T1-T4 testing. Dynamic balance was measured by the time (t) and angular velocity modulus (ω-T5), as well as the pitch angle (θ-T5) and roll angle (φ-T5) indicators in the T5 test. The Pearson product-moment correlation coefficient was used to test the correlation between static and dynamic balance indicators. RESULTS: There is no correlation between ω-T1-ω-T4 and t (P > 0.05), while ω-T1-ω-T4 and ω-T5 (r = 0.19-0.27, P < 0.05) and ω-T1-ω-T4 and θ-T5, φ-T5 (r = 0.18-0.33, P < 0.05) were weakly correlated. There is no correlation between θ-T1-θ-T4, φ-T1-φ-T4 and t (P > 0.05), while θ-T1-θ-T4, φ-T1-φ-T4, and θ-T5, φ-T5 were weakly correlated (r = 0.01-0.28, P < 0.05). CONCLUSIONS: The relationship between static and dynamic balance in preschool children aged 4-5 years is weak. Static and dynamic balance in children needs to be intervened separately for the development of children.

Reliability analysis of inertial sensors for testing static balance of 4-to-5-year-old preschoolers.

BACKGROUND: Balance ability is important for preschoolers' motor and physical development. Portable accelerometers can provide resolution tests and identification of preschoolers with balance defects. RESEARCH QUESTION: Despite previous studies on the balance measures of accelerometer tests, there is a lack of complete analyses for preschoolers aged 4-5 years. In this study, we aim to verify the reliability of measuring the static balance of preschoolers in this age range based on inertia sensors for the acceleration and angular velocity moduli. METHODS: Thirty children wore an inertial sensor in the 5th lumbar vertebra and completed four tests, i.e., standing on a firm surface and on a foam surface with open and closed eyes. The standard deviation of the acceleration modulus and root mean square of the angular velocity modulus were calculated. The analysis was based on the intraclass correlation coefficient (ICC) to determine the internal consistency and feasibility. RESULTS: The ICC of the acceleration modulus was between 0.597 and 0.683 (P < 0.01), and the test-retest reliability was medium. The ICC of the angular velocity modulus was between 0.683 and 0.812 (P < 0.01, P < 0.001), and the test-retest reliability was medium to good. The standard error of measurement (SEM) of the acceleration modulus was between 0.001591 and 0.007248 (g), and the SEM% was between 21.24% and 34.12%. The angular velocity modulus SEM values ranged from 1.296 to 3.441 (deg/s), and the SEM% ranged from 25.17% to 33.26%. The difference between the two tests was evenly distributed on both sides of the mean value, and the difference between the test results was within the consistency limit. SIGNIFICANCE: Inertial sensors can be used to evaluate the static balance ability of preschoolers aged 4-5 years. Further, the angular velocity modulus is more reliable than the acceleration modulus.