Study design and participants
The design of this study was a randomized controlled trial with pre- and post-tests in training and control groups and was done in the sports rehabilitation laboratory of Bu-Ali Sina University. This research was single-blind in which the outcome assessor was unaware of the allocation of research groups. All participants received general information about the purpose of the study and signed the informed consent form prior to participating in the study. The study population consisted of male athletes (20–30 years) from basketball and volleyball sports disciplines who were referred to the sports medical centers in Hamedan, Iran. In the initial review of the athletes' files, 53 athletes with a history of ACLR were found. After more detailed review of the files and interviewing them, 27 people were excluded from the research, based on the inclusion and exclusion criteria (Fig. Participants Flow Diagram.The inclusion criteria were as follows: having a history of unilateral ACL reconstruction (previous 8–12 months) using hamstring tendon autograft; completing the rehabilitation protocol with full returned to sport. The following were the exclusion criteria: having a history of ACL surgery more than once or a recurring knee problem; experiencing an injury of the trunk or lower extremity after post-operative; having a history of surgery on both legs; failing to complete the study (participation of < 80% in the sessions)