The Effect of Fatigue Induced by Exhaustive Exercises on Dynamic Balance and Balance Recovery Time in Active Men with Genu Varum and Normal Knee

Document Type: Research Paper


1 MSc, Department of Corrective Exercises and Sports Injury, Faculty of Physical Education and Sport‌ Sciences, Kharazmi‌ University‌, Tehran, Iran

2 -Associate Professor, Department of Corrective Exercises and Sports Injury, Faculty of Physical Education and Sport Sciences, Kharazmi University, Tehran, Iran


Balance plays a key role in daily and sports activities. The aim of this study was to investigate the effect of fatigue induced by exhaustive exercises on dynamic balance and balance recovery time in active men with genu varum and normal knee. 40 active healthy male students including 20 subjects with genu varum deformity and 20 normal subjects participated in this semi-experimental study. Genu varum deformity was assessed with a caliper and a goniometer. Strand test was used to create fatigue. SPSS software and statistical tests of analysis of combined variance within-between groups, t test and paired t test were used to analyze data. The results of the mean dynamic balance index by paired t test showed that this index increased significantly in the posttest and pretest comparison in both groups (P=0.00). However, independent t test showed that the mean of these changes was not significantly different between the groups (P=0.56). The dynamic balance index in both groups was fully recovered 10 minutes after fatigue. Medial displacement of the gravity line could increase the lateral posture sways in subjects with genu varum and since this deformity causes internal rotation of the leg and pronation of the subtalar joint in weight-bearing condition, leg structure changes can change leg function to control balance.


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