Sarcopenia is defined as the loss of muscle strength and mass associated with aging and is one of the main causes of frailty in older people, and therefore of their ability to age gracefully. Given the aging of the French population, the diagnosis and management of this condition is a major public health issue and, in this context, it is therefore necessary to be able to quickly assess people's skeletal muscle mass.

In its recommendations, French National Authority for Health recommends the use osteodensitometry and bioimpedance analysis (BIA) to assess skeletal muscle mass in the limbs for the purpose of diagnosing sarcopenia. Traditionally, BIA assessment is performed while lying down using adhesive electrodes placed on the hands and feet. The Biody XpertZM3 is a BIA device that allows seated measurement using integrated electrodes, enabling skeletal muscle mass to be assessed by bioimpedance analysis without the use of adhesive electrodes. However, the measurement position could alter the impedances measured and therefore the results obtained compared to other devices on the market as well as osteodensitometer

Inclusion Criteria:

• Men or women aged 60 or over already receiving care at the Day Hospital of the Rehabilitation, Independence and Aging Center or the Frailty Platform of the Rehabilitation, Independence and Aging Center.
• Patients affiliated with or covered by a social security system.
• Patients who have signed an informed consent form in advance.

Exclusion Criteria:

• Vulnerable persons as defined in Articles L1121-5 to -8
• People with pacemakers, implantable defibrillators, or other electronic medical devices
• Musculoskeletal disorders that prevent bioimpedance measurement in a seated position
• Any condition of fluid retention or dehydration
• Absence of a measurement site (muscle resection or amputation)