How does body symmetry influence standing balance?

Abstract

The aim of the study was to determine whether maintaining the standstill balance position was influenced by athlete’s asymmetric morphological characteristics. Thirty-two male healthy sports students participated in this study (age 19.8±1.4 years, body height 182.9±6.8 cm, body weight 79.1±8.1 kg). Morphological characteristics are represented with the differences between the left and the right body side of the forearm girth, upper arm girth, calf girth, thigh girth, long shoulder height, leg lean mass and arm lean mass. The standstill balance result was calculated as a result of factor scores for 9 measurements of 30 seconds (3 measurements of simple standstill, 3 measurements of blinded standstill, and 3 measurements of deafened standstill) collected from the pressure insole system and the difference in ground reaction force (GRF) between the left and the right leg. The results show that the asymmetric leg load in maintaining standstill balance depends on the side differences in the thigh and upper arm girth. The greater difference in the thigh girth in favour of the left side resulted in bigger GRF on the right leg compared to the left leg, and the greater difference in the upper arm girth in favour of the left side resulted in bigger GRF on the left leg. To avoid the one body side overload, it is essential that all sports activities are performed bilaterally.