This is a pilot, prospective, randomized control trial that aim to provide a first estimation of the 3-month post-operative variation in the functional recovery of patients who benefited from an outpatient pre-habilitation program and patients who did not benefit from it.

Open surgery of abdominal aortic aneurysms (AAA) is the reference treatment in a large number of cases. This is a heavy procedure performed in patients around 70 years of age.

In post-operative open aortic surgery, a stay in aftercare and rehabilitation is often necessary, especially in fragile patients.

The goal is to increase the patient's overall functional status to allow him to move away from the threshold below which he loses his independence for activities of daily living.

The pre-habilitation protocol includes 3 parts :

1. Oral nutrition ensures adequate caloric and protein intake to support muscle anabolism
2. Muscle building over a few sessions with a liberal physiotherapist to learn exercises and then independently
3. Cardio-respiratory endurance.

For the experimental group:

Initial visit with adaptive rehabilitation physician, 6-8 weeks prior to surgery:

• Clinical examination with Wood classification - limits and restrictions.
• Assessment of environmental resources
• Definition pre-habilitation protocol and post-operative rehabilitation pathway
• application of the ambulatory pre-approval protocol defined with the adaptive rehabilitation physician.

For the control group:

Support without pre-approval with application of other common practices of the service.

Follow up of both groups:

Post-operative follow-up visits with the surgeon (gathering the necessary information for comparative follow-up).

Mail-out of World Health Organisation Disability Assessment Schedule (WHODAS) 2.0, Euro Qol (EQ)-5D-5L and DIJON questionnaires at 3 and 6 months post-operative.

Inclusion Criteria:

• Patient with an abdominal aortic aneurysm (Thoraco-abdominal aneurysm type 4/Supra renal/Juxta-renal/Sub renal) treated with conventional surgery.
• Surgical indication of aneurysm by size (50-55mm)

Exclusion Criteria:

- Patient requiring urgent management that does not allow for a pre-authorisation protocol of at least 6 weeks.