Following reconstruction of the anterior cruciate ligament (ACL), a standardized rehabilitation protocol is carried out by a physiotherapist. In France, a well-established rehabilitation consensus guides the first phase of 3 months postoperatively and patient compliance is generally excellent. The next phase should allow a return to sport (RTS) following a continuum depending on the objectives of the sport's patient, starting with a return to running activities (RTR) and a preparatory phase for a RTS which may be authorized at 6 months post-op.

This multicentre randomized control trial aims to evaluate the effectiveness of an individualized and optimized rehabilitation program guided by monthly assessments carried out by physiotherapists from the 3rd to the 6th month postoperatively to reduce the risk of new ACL injuries (operated or healthy knee), compared to standard management.

Each year more than 40,000 surgical reconstructions of the anterior cruciate ligament (ACL) by ligamentoplasty are performed in France; the rupture being most often the result of sports practice. Following this surgical reconstruction of the ACL, a standardized rehabilitation protocol is carried out by a masseur-physiotherapist. A well-established rehabilitative consensus guides the first phase of the 3 months post-operative and patient compliance is generally excellent. The next phase should allow the return to sport (RTS) by following a continuum according to the objectives of the athlete patient. In this continuum, authors distinguish the return to sports activities in the axis, such as running (RTS1), preparing the return to training (RTS2), and much later will be done by the return to competition (RTS3).RTS2, which is probably the most delicate stage due to the highly variable progression from one patient to another, is generally allowed from the 6th month post-operative, after the realization and validation of a battery of tests assessing the athlete's ability to resume training.Despite this precaution, there is a major risk of new injury (20%), especially in the contralateral knee (12%) requiring new, longer, more restrictive rehabilitation care with an additional 3 to 12 months' incapacity for work or sport.. As the risk of "re-injury" of the knee seems independent of the surgical technique used and the first 3 months of rehabilitation, the rehabilitative management of this phase of 3 to 6 months post-operative appears decisive in the prevention of a new injury. The return to running (in the RTS1) therefore seems a major objective for rehabilitation and will build the necessary foundation for the resumption of the patient's favorite sport, RTS2. However, to allow the return to running, no objective criteria have been validated to date and no consensus is identifiable in the scientific literature. It is the same for his preparation and the gradual resumption of running. Thus, an optimized rehabilitation between the 3rd and 6th month, based on objective evaluations of the patient's functional abilities allowing personalized rehabilitation, including guided and individualized running training, could reduce the risk of new ACL injuries (operated or healthy knee) by better preparing the patient for RTS2: the return to his favorite sport

Inclusion Criteria:

• Affiliation to the French Social Security system
• Patient who has had an ACL reconstruction regardless of the standard surgical technique used
• Patient with a sports activity, pivot and/or contact (e.g. soccer, basketball, handball, rugby, judo...) and practiced in competition (Tegner sports activity scores >7 and Marx scores >11 before the accident.
• Patient wishing to return to competitive sport
• Consent signed by the patient

Exclusion Criteria:

• Contralateral or bilateral involvement or operated on for a re-injury of the ACL
• Patients with a medical contraindication to the performance of one of the tests
• Patients suffering from a neurological (motor and/or sensitive), vestibular or rheumatic pathology
• Patient performing rehabilitation with a physiotherapist who does not wish to participate in the study.
• Pregnant or breastfeeding woman
• Patient under guardianship or curators