Shahid Beheshti University of Medical Sciences The Scientific Journal of Rehabilitation Medicine 2251-8401 13 1 2024 03 20 The Effect of Fatigue on the Time to Stability in Head Movement in Soccer Players With a History of Anterior Cruciate Ligament Reconstruction The Effect of Fatigue on the Time to Stability in Head Movement in Soccer Players With a History of Anterior Cruciate Ligament Reconstruction 148 161 1101678 10.32598/SJRM.13.1.10 FA Moosareza Ghorbani Department of Sport Injury and Corrective Exercise, Faculty of Sport Sciences, University of Guilan, Rasht, Iran. 0000-0003-4520-0826 Roghayeh Jalil Piran Department of Sports Injury and Corrective Exercises, Faculty of Physical Education and Sports Sciences, Allameh Tabatabaei University, Tehran, Iran. 0000-0003-0376-5538 Farideh Babakhani Department of Sports Injury and Corrective Exercises, Faculty of Physical Education and Sports Sciences, Allameh Tabatabaei University, Tehran, Iran. 0000-0002-1035-5011 Journal Article 2021 09 26 <strong>Background and Aims</strong> Delay in achieving stability is one of the factors that can cause injury and re-injury in athletes. Because many injuries occur during fatigue, the present study aimed to compare the effect of fatigue on the time to stability in the head movement of players who have undergone anterior cruciate ligament (ACL) reconstruction with healthy players.<br /><strong>Methods </strong>The present study is quasi-experimental. Twenty-four professional soccer players participated in the study. Twelve healthy, active professional soccer players (control group) and 12 soccer players with reconstructed anterior cruciate ligament by hamstring graft (experimental group) participated in this study. Also, 6 to 24 months should have passed since their ligament reconstruction. After jumping and crossing an obstacle to a height of 7.5 cm, the participants performed the task of heading and landing on the force plate. These movements were repeated after the fatigue protocol. Information was collected by the force plate (Kistler Instruments Sweden). Multivariate analysis of variance at the significant level of P <0.05 was used for comparison between groups.<br /><strong>Results </strong>According to the findings, fatigue affected the time to stability in the internal-external direction (P <0.05). However, no difference was observed between the two groups in the internal-external direction before fatigue. Also, no significant difference was observed between the two groups when achieving stability before and after fatigue in the anterior-posterior and vertical directions.<br /><strong>Conclusion</strong> It seems that a plyometric fatigue training session cannot differentiate between healthy soccer players in the anterior-posterior and vertical directions from players who have undergone anterior cruciate ligament reconstruction. However, this difference was observed in the internal-external direction after fatigue.  <strong>Background and Aims</strong> Delay in achieving stability is one of the factors that can cause injury and re-injury in athletes. Because many injuries occur during fatigue, the present study aimed to compare the effect of fatigue on the time to stability in the head movement of players who have undergone anterior cruciate ligament (ACL) reconstruction with healthy players.<br /><strong>Methods </strong>The present study is quasi-experimental. Twenty-four professional soccer players participated in the study. Twelve healthy, active professional soccer players (control group) and 12 soccer players with reconstructed anterior cruciate ligament by hamstring graft (experimental group) participated in this study. Also, 6 to 24 months should have passed since their ligament reconstruction. After jumping and crossing an obstacle to a height of 7.5 cm, the participants performed the task of heading and landing on the force plate. These movements were repeated after the fatigue protocol. Information was collected by the force plate (Kistler Instruments Sweden). Multivariate analysis of variance at the significant level of P <0.05 was used for comparison between groups.<br /><strong>Results </strong>According to the findings, fatigue affected the time to stability in the internal-external direction (P <0.05). However, no difference was observed between the two groups in the internal-external direction before fatigue. Also, no significant difference was observed between the two groups when achieving stability before and after fatigue in the anterior-posterior and vertical directions.<br /><strong>Conclusion</strong> It seems that a plyometric fatigue training session cannot differentiate between healthy soccer players in the anterior-posterior and vertical directions from players who have undergone anterior cruciate ligament reconstruction. However, this difference was observed in the internal-external direction after fatigue.  https://medrehab.sbmu.ac.ir/article_1101678_de90fdf62e51782026af479fc7e5873f.pdf