Comparison of the effect of local fatigue on the variability of knee extensor muscle torque in healthy subjects with anterior cruciate ligament rupture
Poster Presentation XML
Paper ID : 1721-11THCONF
2assistant proffessor of faculty of pysical education and sport sciences, kharazmi university
Introduction: The purpose of this study was to investigate the effect of local fatigue on knee extension torque variability in healthy subjects and patients with ACL reconstructed knees.eleven patient’s with ACL reconstructed knees (ACL-R group), and ten healthy controls (controls group), completed measures of maximal effort isokinetic knee extension.
Methodology: All subjects were evaluated between 7 months and 3 year after ACL reconstruction with a Biodex isokinetic dynamometer (System3 Pro) with test protocol CON/CON at 60◦/s with 5 repetitions, respectively .In the calculation of local muscle fatigue, the fatigue index was used, which is calculated by dividing the labor done in the first one-third of the repetitions by that done at the final one-third of the repetitions, and multiplying by 100 to express a unit in percentage (i.e., asa discrete quantitative variable). Coefficient of Variation (CV) was used to calculate torque variability. T-test analyses were used for data analysis.
Results: A total of 11 individuals with primary, unilateral ACL-R (age22.91 ± 2.38 years, height 175.55±5.57cm, mass 68.26± 4.5 kg) and 10 individuals with no history of substantial lower extremity injury or surgery who served as controls (age23.11 ± 1.28 years, height 170.8±7.27cm, mass 65.8±7.2kg). The ACL-R group demonstrated greater torque than the control group at baseline (ACL-R 0/460, control 0.662) and after-fatigue (ACL-R 0/851, control 0/320).
Discussion: The results allow us to conclude that there was no significant difference(P>0.05) between the per-fatigue in torque variability and there was significant difference(P<0.05) between after -fatigue in torque variability of extensor knee muscles.These results indicate that fatigue in ACL-R is one of the most destructive factors of torque variability.