1.    Introduction
Volleyball athletes are more susceptible to knee joint injuries than others due to their movement patterns, including jumping, landing, and side-cutting movements (2). Research indicates that incorrect biomechanics during functional tasks such as jump-landing are significant contributors to knee joint injuries (3). Therefore, it is crucial to accurately control the alignment of the lower body and trunk during landing. Additionally, the lack of balance control is identified as another risk factor for knee injuries (8, 2). Recently, researchers have recognized the importance of preventing skeletal-muscular injuries by correcting improper movement patterns using sports exercises that provide simultaneous feedback (12). Given its functionality, TRX exercises can simulate many key movements in volleyball and also position athletes in scenarios that mimic the primary mechanisms of knee joint injuries (2).
Furthermore, previous research has not sufficiently addressed injury prevention among female volleyball players, who represent valuable human capital for the country. Therefore, the purpose of this study is to investigate the impact of movement pattern correction exercises using TRX on the landing biomechanics and balance of female volleyball players prone to knee injuries.
2.    Methods
The present research is semi-experimental due to the intervention and targeted selection of subjects. The statistical population for this study consists of all teenage girl volleyball players from schools in the 7th district of Tehran. The statistical sample was determined to be 24 individuals using G-power software, with a power of 0.85, a significance level of 0.05, and an effect size of 0.5. The research sampling method is purposeful and accessible. In the initial stage, the tuck-jump test was employed to identify athletes prone to knee injuries. Once the girl volleyball athletes predisposed to knee injuries were identified, they were randomly divided into two groups of 12 people each – a training group and a control group. The athletes were then instructed to undergo measurements based on a schedule and according to individual preferences. The initial measurement session included the assessment of anthropometric characteristics, the Landing Error Scoring System (LESS) test, and static and dynamic balance tests. Stork's test, utilized for evaluating static balance, has been reported to have good reliability (0.66) by Farhadi, citing Rossiter (21). The Y dynamic balance test, known for its high reliability (ICC = 0.80 - 0.93), was used to assess the balance of the subjects (20). Landing biomechanics were evaluated using the Landing Error Scoring System test.
Following the completion of the pre-test phase, the subjects in the training group engaged in TRX exercises for 6 weeks, receiving feedback on correcting movement patterns. The TRX training program included selected exercises performed three times a week for 6 weeks, with each session lasting between 20-25 minutes. The exercises took place in the sports class of the schools under the full supervision of the researcher, who is also the sports secretary and a TRX trainer. Immediately after the 6-week training period, all participants from both groups returned to the gym for post-test measurements, where all measurements conducted in the pre-test session were repeated. The research findings between the two groups in the post-test stage were evaluated using paired t-tests for intra-group changes and covariance analysis tests.
3.    Results
Examining the intra-group results of the paired t-test reveals a significant improvement over time in the variables of static and dynamic balance, as well as the LESS score, for the subjects in the experimental group during the post-test phase compared to the pre-test (p < 0.05). Conversely, in the control group, there was no observable change in any of the mentioned variables in the post-test compared to the pre-test (p > 0.05).
The results of covariance analysis, after controlling for the pre-test effect as a covariate, demonstrate a significant difference in the variables of static and dynamic balance, along with LESS scores, between the experimental and control groups in the post-test (p < 0.05).
4.    Conclusion
The results of the research indicate that engaging in movement pattern correction exercises using TRX for 6 weeks led to improvements in static and dynamic balance, as well as a reduction in landing error scores among the subjects in the experimental group. Providing simultaneous feedback to correct improper techniques in using the lower limbs during functional tasks likely enhanced the coordination of the neuromuscular system, potentially increasing muscle tension and joint stability (12). Consequently, heightened sensory awareness contributed to improved motor control, reducing the likelihood of executing traumatic movements during sports activities (14). One notable feature of TRX exercises is their effective activation of core stabilizer muscles. This activation enhances the athlete's ability to control the trunk, subsequently ensuring proper control of the lower limbs, especially during landing. Movement pattern correction exercises with TRX can significantly mitigate the risk of performing traumatic movements with unnatural joint alignment (2).
In conclusion, based on the results of the present research, it can be asserted that incorporating movement pattern correction exercises using TRX offers a viable solution for enhancing the balance and biomechanics of landing in volleyball players prone to injury. Therefore, it is recommended for coaches and athletes in the field of volleyball to integrate this training method with the goal of preventing anterior cruciate ligament injuries.

Ethical Considerations
Compliance with ethical guidelines
All ethical principles were considered in this article. The participants were informed about the purpose of the research and its implementation, and they were also assured about the confidentiality of their information. Moreover, they were allowed to leave the study whenever they wished, and if desired, the results of the research would be made available to them.
Funding
This research did not receive any grants from funding agencies in the public, commercial, or non-profit sectors.
Authors' contributions
All authors equally contributed to preparing article.
Conflicts of interest
The authors declared no conflict of interest.