1.    Introduction
Anterior cruciate ligament (ACL) injuries are among the most common knee injuries in sports. Despite efforts by researchers and physicians to reduce the risk, ACL injuries have doubled over the past two decades. While the relative risk of these injuries is 2-8 times higher in females compared to males, overall, due to increased participation in contact and team sports, ACL injuries are more prevalent in males (1). 85% of these injuries occur in non-contact situations, particularly during maneuvers such as cutting, landing, and pivoting. A wide spectrum of non-contact injuries includes ACL tears and patellofemoral pain syndrome resulting from irregular knee joint loading due to excessive dynamic knee valgus (2). Typically, individuals with non-contact knee injuries exhibit alterations in lower limb kinematic variables during functional tasks. Specifically, increased knee movement in the frontal plane during functional tasks, known as knee valgus, predicts non-contact ACL injuries and patellofemoral pain (3, 4). Landing maneuver is a fundamental task in high-risk sports activities such as volleyball, handball, and basketball. Landing technique can affect ground reaction force and lower limb kinematics. Therefore, poor landing mechanics with inadequate motion at the hip and knee joints not only reduce shock absorption but also increase the risk of lower limb injuries. An example of poor landing technique is excessive dynamic knee valgus, characterized by knee valgus, hip internal rotation, and lateral displacement of the patella (5-7). Deficiencies in movement patterns lead to changes in Lower Extremity Kinematics and inappropriate loading on the joints, which can result in non-contact injuries to the anterior cruciate ligament. Therefore, it is recommended to design exercise programs with the aim of improving deficient movement patterns. The aim of the study is to investigate the effect of an eight-week kinematic feedback training program on male athletes with selected movement control issues in jumping tasks.
2.    Methods
The present research is a randomized clinical trial conducted before and after the intervention. Thirty-four male recreational athletes with movement control defects (dynamic knee valgus and/or quadriceps dominance) were selected based on study criteria and then randomly assigned to control and intervention groups in a 1:1 ratio. Kinematic data were recorded while participants performed jump-landing tasks (vertical jump, tuck jump, and countermovement jump) in two stages before and after the two-month jump training program. Additionally, during the two-month training program and movement tasks, the intervention group received external feedback, first through training videos and then verbally during the task, e.g., align the knee with the toes, press the knee towards the wall (external source). Data analysis utilized two-way analysis of variance and Bonferroni statistical tests for each movement task with a significance level of P < 0.05.
3.    Results
The results of the present study, based on the statistical test of two-way analysis of variance, demonstrated that an eight-week feedback training program significantly affected the kinematics of the hip, knee, and ankle in athletes with movement control defects (dynamic knee valgus and quadriceps dominance) during jump-landing tasks (drop vertical jump, tuck jump, and countermovement jump). Specifically, in all three jumps and in four phases (eccentric, concentric, maximum knee flexion, and landing moment), the feedback group showed a significant increase in the range of motion of the hip, knee, and ankle. Additionally, the feedback reduced the amount of knee valgus. Bonferroni's post hoc test results indicated that the feedback group exhibited a significant improvement in the valgus angle compared to its pre-test, with the greatest effect observed in the vertical jump.
4.    Conclusion
An eight-week feedback training program significantly influences the kinematics of the hip, knee, and ankle in athletes with movement control deficiencies (dynamic knee valgus and quadriceps dominance) during jump-landing tasks (vertical jump, tuck jump, and countermovement jump), resulting in increased range of motion in the lower limb joints and consequently reducing the risk of anterior cruciate ligament injury. The eight-week feedback training program also significantly affects the angle of knee valgus in athletes with movement control deficiencies (dynamic knee valgus and quadriceps dominance) during jump-landing tasks (vertical jump, tuck jump, and countermovement jump). Therefore, feedback leads to a reduction in the angle of knee valgus in all three types of jumps, with the greatest effectiveness observed in the vertical jump.

Ethical Considerations
Compliance with ethical guidelines
Ethical Considerations this study was the result of a doctoral dissertation with ethics code (IR.GUILAN.REC.1402.001) from Guilan University. All ethical standards governing clinical research, such as obtaining informed and free consent, non-harm to participants, confidentiality of information, notice of withdrawal from the study at any time, privacy and justice have been observed.
Funding
This study is the result of a doctoral thesis of Guilan University and has not received financial support from any other organization.
Authors' contributions
Collecting and combining data by M.A; Conceptualization, ideation, study design and editing were done by all authors.
Conflicts of interest
The authors whose names are mentioned certify that, except for Guilan University and Guilan University of Medical Sciences, there is no affiliation or partnership with any organization or institution with any financial interest (such as fees, scholarships, participation in speakers' bureau, membership, employment, consulting, stock ownership, or other equity interests; patent licensing arrangements), or had no non-financial interest (such as personal or professional relationships, affiliations, knowledge, or beliefs) in the subject matter or material discussed in this manuscript.