ABSTRACT
OBJECTIVE: The present study aimed to compare the effects of quadriceps or calf muscles fatigue on static and dynamic standing balance in young healthy adult males. METHODS: Forty-five healthy, physically active male adults aged 18-30 years were randomly divided into three groups; Quadriceps muscle fatigue group (n=15), Calf muscles fatigue group (n=15), and a control group (n=15). The Modified Clinical Test of Sensory Interaction on Balance, Unilateral Stance, and Limits of Stability (reaction time and movement velocity) were selected as outcome measures for this study. RESULTS: The results showed a non-significant difference between pretest and posttest balance scores (p>0.05) for quadriceps and calf muscles fatigue on balance. Similarly, there were non-significant differences in posttest balance scores when comparing fatigue effects between the groups (p>0.05). CONCLUSIONS: These results suggested that the fatigue of the quadriceps or calf muscles did not influence standing balance in healthy young adult males. Future longitudinal studies are recommended to further understanding the mechanisms behind localized muscle fatigue effects on standing balance in subjects of different age groups of both genders.