For the cohort study, 500 frail older adult patients will be evaluated by means of instrumental and functional tests that assess their functional capacity, in addition to ultrasound imaging to study sarcopenia and nutrition, as well as psychological variables. The correlation between all functional, ultrasound, nutritional, and psychological variables will be analyzed. Through GLIM diagnosis, anthropometric data (weight, height, BMI) as well as analytical data including inflammation information (CRP and albumin) will be used to reach a diagnosis that allows comparison/correlation with the rest of the variable parameters. All available information will be collected during the follow-up in order to generate Machine Learning on the objective evolution and symptomatology of these patients, generating profiles that facilitate the most accurate and appropriate treatment for each patient.

The correlation between all functional, ultrasound, nutritional, and psychological variables will be analyzed. Through GLIM diagnosis, anthropometric data (weight, height, BMI) as well as analytical data including inflammation information (CRP and albumin) will be used to reach a diagnosis that allows comparison/correlation with the rest of the variable parameters.

The grip strength in both hands will be measured by measuring the maximum grip strength. A bulb dynamometer will be used for this measurement.

It will be evaluated by means of the the EuroQol 5-dimensions 5-levels (EQ-5D-5L), which is a generic instrument for measuring health-related quality of life. The patient himself assesses his state of health, in levels of severity by dimensions The first allows the respondent to define the state of health according to the EQ-5D multi-attribute classification system, composed of 5 dimensions (mobility, self-care, activities of daily living, pain/discomfort and anxiety/depression), and in each of them there are 3 levels of severity (1, 2 or 3).

The Barthel Index evaluated one's ability to care for him/herself through ten activitiesof daily living like feeding, bathing, grooming, dressing, bowel and bladder control,toileting, chair transfer, ambulation, and stair climbing; the maximum score is 100 pointsand the higher the score, the greater the functional independence of the patient. Thefollowing baseline data regarding age, sex, and admission diagnosis were also collected .

The Trunk Control Test (TCT) evaluated four aspects of trunk movement, swinging to both sides, sitting balance, and rising from the floor; individual items are scored from 0 (incapable) to 12 (ability to perform the movement but with an unusual style) and 25 (ability to perform the movement correctly).

To evaluate the pain that the patient has, we use the VAS. This is a 100 mm line that measures pain intensity. The left end of the line represents the absence of pain, while the right end represents the worst pain imaginable. The numerical pain intensity scale adds a numerical graduation where 1 is no pain and 10 is the worst pain imaginable. The confidence and reliability of this scale has been approved and validated in different studies.