The effect of 6 weeks of plyometric exercises on the strength of muscles around the knee and lower extremity Functional performance in male underwent Anterior cruciate ligament reconstruction: A clinical trial study

To determine the effect of 6 weeks of plyometric training on knee muscle strength and lower extremity functional performance in male athletes following anterior cruciate ligament reconstruction

This is a randomized, controlled, double-blind clinical trial with a parallel design. Thirty male athletes (18–35 years) with ACL reconstruction will be randomly assigned (1:1) to either a plyometric training group or a control group. The intervention lasts 6 weeks (3 sessions/week). Muscle strength and lower limb function will be assessed pre- and post-intervention. The outcome assessor and data analyst will be blinded.

The study will be conducted in Sari at a sports rehabilitation/training center under supervision of a physician and corrective exercise specialist. The intervention includes 3 supervised sessions per week for 6 weeks.

Inclusion criteria؛ Men between the ages of 18-35 years and confirmation of anterior cruciate ligament reconstruction (patellar tendon and hamstring autograft) by a knee specialist with radiography and MRI, no history of back and lower limb surgery (other than the knee), and a history of ACL reconstruction at least 6 months and no more than 12 months ago. Exclusion criteria؛ meniscus surgery with anterior cruciate ligament, use of allograft in cruciate ligament surgery, history of performing plyometric exercises, failure to complete rehabilitation phases before 6 months, age over 35 years

For 6 weeks, 3 sessions per week (each session 50 minutes), they perform plyometric exercises including jumping, zigzag, lateral, and vertical hopping under the supervision of a corrective exercise specialist.

Quadriceps strength Hamstring strength Hamstring-to-quadriceps strength ratio (H/Q) Lower limb functional performance (single-leg and triple hop tests)

In this quasi-experimental study, 30 male athletes (with a history of one ACL reconstruction within the past 6 to 12 months) who were eligible for inclusion in the study were purposively identified and then divided into two equal groups (15 in the plyometric training group and 15 in the control group) by simple randomization. The randomization process was performed as follows: An independent person, unaware of the study objectives, randomly generated a list of numbers from 1 to 30 using random number generation software (such as Excel or Randomizer.org). Half of the numbers (e.g., even numbers) were assigned to the training group (Plyometric) and the other half (odd numbers) were assigned to the control group. In order to prevent any bias, the assignment of subjects to groups was done by an independent person and the researcher was unaware of the group assignment until the final list was completed (allocation concealment). During the randomization process, inclusion and exclusion criteria were predetermined, and only those who met all inclusion criteria were included in this allocation.

1. Blinded Outcome Assessor: All outcome measurements, including isokinetic strength assessments of the quadriceps and hamstrings, as well as functional performance tests of the lower extremity (e.g., single-leg hop tests), will be conducted by a trained assessor who is completely blinded to the participants’ group allocation. The outcome assessor will not be involved in the intervention phase and will only participate in the pre-test and post-test assessments. Participants will be instructed not to disclose their group assignment or any intervention details during testing. All assessments will be performed under standardized conditions (time, location, and equipment) for all participants. 2. Blinded Data Analyst: The collected data will be coded (e.g., as Group A and Group B) before statistical analysis. The data analyst will be blinded to the actual group identities throughout the entire analysis process. Group codes will only be revealed after statistical comparisons and interpretations are completed.

Due to ethical considerations and the need to protect the confidentiality of participants’ personal information, individual-level raw data will not be made publicly available. Sharing such data could potentially lead to identification of participants even after anonymization

The dataset includes demographic information (age, height, weight, BMI), isokinetic test results (quadriceps strength, hamstring strength, H/Q ratio), and lower limb functional performance (single-leg hop and triple-hop tests) in male athletes following ACL reconstruction. Data are collected at two time points (baseline and week 6) and stored in digital formats (Excel/SPSS).

Data will be available upon request and with ethics committee approval after study completion and initial analysis (within 12 months after study end) and will remain accessible for 3 years.

Data and documents will be accessible only to qualified researchers who submit a written request and obtain approval from the ethics committee.

Data and documents will be used solely for scientific and research purposes. Access will be granted only upon written request, ethics committee approval, and a signed commitment to maintain confidentiality and not to use the data beyond the agreed research scope.

Name: Reza Rezaeian vaskasi Position: Principal Investigator Email: rezaeianr7@gmail.com Phone: 00989360679338 Location: Sari Sports Medical Board

Access requests must be submitted in writing to the Principal Investigator. Each request will be reviewed by the ethics committee. If approved and a confidentiality agreement is signed by the requesting researcher, the data/documents will be provided within the defined time frame.