The goal of this clinical trial is to determine whether a multicomponent physical exercise program improves functional and cognitive capacity in hospitalized older adults compared to the usual hospital care. The main questions it aims to answer are:

• Does a multicomponent physical exercise program improve functional and cognitive capacity?
• Is there a difference between a multicomponent physical exercise program and usual care regarding functional and cognitive outcomes after an acute hospitalization?

Researchers will compare a multicomponent physical exercise program (containing strength, balance, and walking exercises) to the usual care of the hospital to see if the program is better at maintaining or enhancing functional and cognitive outcomes

Participants will:

• Participate in multicomponent physical exercise program or receive usual care. The multicomponent group will complete the program daily for the entire hospitalization period;
• Perform functional and cognitive tests at the beginning and end of hospitalization;
• Be contacted by researchers 3, 6, and 12 months after hospital discharge.

Aging is a natural and multifactorial process associated with various physiological and behavioral changes. Some of these changes can lead to increased physical inactivity, resulting in declines in functionality and increased vulnerability to diseases. During acute hospitalization, one of the several clinical consequences is excessive bedrest, even when walking is possible. Which leads to functional decline, defined as iatrogenic nosocomial disability. The literature already well describes that a multicomponent physical exercise program improves functional and cognitive capacity in frail, institutionalized, or hospitalized old people. However, a program based on this model has not yet been implemented during short-term hospitalization in Brazil. Therefore, this study aims to evaluate the effects of a multicomponent program on functional performance and cognitive function in elderly individuals with different conditions of frailty during acute hospitalization at the "Hospital de Clínicas de Porto Alegre". Functional performance will be assessed using the Short Physical Performance Battery, Timed Up and Go, 6-meter gait velocity, handgrip strength, and muscle power in 3-times-sit-to-stand. Cognitive performance will be evaluated through the Mini-Mental State Examination, Geriatric Depression Scale-15, and part "A" of the Trail Making Test. Affectiveness of the intervention will be measured using the Affectivity Scale. Participants will be randomized into two groups: multicomponent training based on VIVIFRAIL (MT) and control group. Participants in both groups will receive usual hospital treatments, including physiotherapy sessions in the morning. Participants in the MT group will perform the exercise program adjusted to their frailty and with progressive volume in the afternoon. On hospital discharge day, patients will be re-evaluated. Statistical analysis will be conducted using Generalized Estimating Equations, adopting group and time factors with two stratifications. Post-hoc LSD tests will be used to identify differences between groups. Analyses will be performed both per protocol, for individuals who complete the study, and by intention-to-treat, including those who do not complete the protocol. Results will be considered significant when p ≤ 0.05 and presented as percentage change and standard deviation with a 95% confidence interval.

Inclusion Criteria:

• Aged 70 years or older;
• Capable of ambulating independently or with assistance;
• Pre-hospitalization Barthel Index ≥ 60;
• Does not have a terminal illness;
• Able to participate in the testing procedures and the multicomponent training program, as determined by the physician;
• Capable of providing informed consent for participation in the study.

Exclusion Criteria:

• Duration of hospitalization < 3 days;
• Lack of willingness to complete the phases of the project;
• Complications related to disease progression or intervention.

After the end of study, a deidentified data set will be available upon request

After the end of the study, no end date for sharing IPD was set.

Researchers affiliated with recognized research institutions, with a research project approved by an ethics committee for the protection of human subjects, will have access to the following data: the study protocol, statistical analysis plan, informed consent form, clinical study report, and analytic code. They can request access by emailing the principal investigator with all necessary information. After review, a data table will be sent.