Normative Values of Y Balance Test and Isometric Muscle Strength among Saudi School Children

Abstract

Abstract Background To establish children-specific reference values for the Y-balance test (YBT) and Isometric muscle strength in school children of Saudi Arabia and to elucidate the relationship between YBT performance and lower limb muscle strength. Materials & Methods Healthy School children (51 males) aged 12–15 years volunteered to participate in this study. Participants completed the YBT and maximal isometric muscle strength testing for knee extensors and flexors in a single testing session. Descriptive statistics were used to compute the YBT and muscle strength reference values. Paired t-tests were used to examine interlimb differences. Pearson’s correlation coefficient was used to quantify the linear relationships between YBT distances and lower limb strength. Results Tabulated children-specific reference values were presented for the right, left, dominant and non-dominant limbs. Participants exhibited longer distance in the posteromedial direction standing on the right (p=0.04), stronger knee extensors (p=0.03) on the dominant side and stronger knee flexors in the right side (p=0.01) and in the dominant side (p=0.01). Knee flexors muscle strength was positively related to the reach distances of the YBT in both the right and the left lower extremity (P<0.05). Conclusion The current study provided the reference value for the YBT and muscle strength for the knee extensors and flexors in male children in Saudi Arabia. The interlimb difference in YBT performance was noted in only the posteromedial direction and the dominant side had stronger knee flexors and extensors. Muscle strength of the knee flexors was positively related to the reach distance in the YBT.