INTRODUCTION Physical exercise in frail individuals has demonstrated benefits in variables such as reduced mortality risk and improved frailty and quality of life. Specifically, the most beneficial type appears to be multicomponent exercise, which includes strength, endurance, balance, and gait training. Within this field, the VIVIFRAIL project is an internationally recognized physical exercise promotion program.

OBJECTIVES To analyze the effects of an individualized multicomponent physical exercise program as an effective method for preventing/improving functional status and frailty in individuals admitted to an intermediate care hospital (ICH).

To assess whether improvements in functionality/frailty are maintained 3-4 months after discharge and to evaluate the impact of the program on quality of life variables and health indicators at 6 months.

METHODOLOGY Design: randomized clinical trial with two groups (control and intervention) and 6 months of follow-up.

Study population: adults older than 65 years admitted to an intermediate care hospital (ICH).

Inclusion criteria: baseline Barthel Index ≥60, ability to communicate, ambulate, and complete the exercise program.

Primary variables: functionality (Short Physical Performance Battery - SPPB) and frailty (Frail-VIG Index).

Secondary variables: grip strength, depressive symptoms, fear of falling, mortality, institutionalization, hospital admissions/emergency room and primary care visits, level of physical activity, medications (number, analgesics, opioid use, antidepressants, anxiolytics), and quality of life.

Sample size: assuming a 15% loss to follow-up, the final required sample size is 120 patients. Linear mixed-effects models will be used with a significance level of 0.05.

Introduction:

-Background Frailty is defined as "a medical syndrome with multiple causes and contributing factors characterized by diminished strength, endurance, and physiological function, increasing an individual's vulnerability to developing increased dependency and/or death." Its prevalence is high and increases with age.

With aging, the functional capacity of the neuromuscular, cardiovascular, and respiratory systems progressively declines, increasing the risk of frailty.

The reduction in muscle strength/power together with functional loss is one of the main factors threatening patients' autonomy. This situation worsens after hospitalization due to bed rest, polypharmacy, and physical impairment following acute illnesses.

The benefits of physical exercise in aging, especially among frail individuals, have been the subject of numerous studies. Regular physical activity improves both physical and mental function globally and may reverse some effects of chronic diseases, helping older adults maintain mobility, independence, and autonomy (improved functional capacity). It has also been shown to reduce mortality risk and institutionalization while improving frailty and quality of life.

The effects of physical exercise may be comparable to or even greater than those of pharmacological treatments for the prevention of cardiovascular disease and mortality reduction, with minimal adverse effects. However, despite the proven benefits, participation rates in physical activity among older adults remain low.

In particular, multicomponent physical activity programs-which include strength, endurance, balance, and gait training-have shown the greatest benefit, proving to be effective tools for preventing sarcopenia and functional decline. They have also demonstrated utility in reducing falls, cognitive decline, and depressive symptoms. Furthermore, exercise has a modulatory role in inflammation, increasing nociceptive thresholds and modifying pain perception.

Within this type of physical training, the VIVIFRAIL project is an internationally recognized exercise promotion program for preventing frailty and falls in older adults, both in community and hospital settings. The effectiveness of this program has been demonstrated in multiple previous studies.

Despite the scientific evidence supporting exercise prescription as an excellent non-pharmacological intervention, it is still uncommon for exercise to form part of the therapeutic plan at hospital discharge. In addition, adherence to exercise programs is often difficult, mainly because of patient motivation deficits and insufficient follow-up by healthcare professionals.

This study aims to evaluate the impact of prescribing individualized multicomponent physical exercise at discharge from an intermediate care center and its medium-term impact on health outcomes such as functional capacity, quality of life, polypharmacy, pain control, falls, mood, muscle strength, institutionalization, hospitalization, and mortality.

Unlike previous studies, frailty in this study will be measured using the VIG-Frail Index, which provides a rapid, multidimensional, and effective assessment of frailty, with optimal predictive capacity for 2-year mortality.

Through multicomponent physical exercise, we aim to demonstrate improvements in frailty, functionality, quality of life, and emotional well-being in geriatric patients, thereby reducing the risk of institutionalization. We also believe it may improve caregivers' quality of life by reducing the level of support required as patient functionality improves.

The study proposes a change in the discharge model currently used in intermediate care hospitals, where the intervention plan will include the prescription of an individualized physical exercise program that has not previously been implemented.

-Working Hypothesis Patients admitted to an Intermediate Care Hospital (ICH) who participate in an individualized multicomponent physical exercise program during the 3-4 months following discharge will achieve greater improvements in functional status and frailty compared with those who do not participate in the program.

In the medium term (6 months), these individuals will also demonstrate improved quality of life and lower rates of institutionalization, hospital admissions, emergency department visits, primary care consultations, and mortality.

- Objectives Primary Objective To evaluate functionality and frailty 3-4 months after discharge from intermediate care in a group of patients prescribed a home-based physical exercise program (VIVIFRAIL), and to compare them with a group of similar characteristics who did not receive this prescription.

Secondary Objectives

• To evaluate and compare both groups at 3-4 months in terms of:

  • number of falls,
  • fear of falling,
  • polypharmacy,
  • number of analgesics,
  • use of opioids, antidepressants, and anxiolytics,
  • pain control,
  • muscle strength,
  • quality of life,
  • and mood status.

• To evaluate 6-month mortality in the group receiving physical exercise prescription compared with the control group.

• To evaluate healthcare resource utilization at 6 months, including emergency department visits, primary care consultations, hospitalizations, and institutionalization.

  • Methodology

Study Design Randomized clinical trial with two groups: control and intervention.

Study Setting This is a single-center study that will be conducted at Hospital de Sant Andreu, Sant Andreu Salut, Manresa, an Intermediate Care Hospital (ICH).

Reference Population Patients admitted to Hospital de Sant Andreu, Sant Andreu Salut, Manresa.

Study Subjects The study will be conducted in an Intermediate Care Hospital in Manresa (Sant Andreu Salut. Hospital de Sant Andreu). The hospital has 155 beds. Admissions mainly come from the referral acute care hospital (Hospital Sant Joan de Déu de Manresa, Fundació Althaia), either from the emergency department or inpatient wards. Admissions may also come directly from primary care settings, including private homes and nursing homes.

The study will include selected patients who meet the inclusion criteria and agree to participate.

Inclusion Criteria

• Patients aged ≥65 years admitted to Hospital Sant Andreu (Manresa).
• Baseline Barthel Index ≥60.
• Ability to communicate, ambulate, and complete the exercise program.

Exclusion Criteria

• Severe cognitive impairment.

• Medical conditions contraindicating physical exercise, including:

  • severe valvular heart disease,
  • uncontrolled heart failure,
  • unstable angina,
  • recent myocardial infarction,
  • uncontrolled arrhythmias,
  • acute infectious disease,
  • uncontrolled hypertension,
  • myocarditis,
  • pericarditis,
  • active endocarditis,
  • aortic dissection,
  • poorly controlled diabetes mellitus,
  • recent fracture within the last month (strength training contraindication).

Withdrawal Criteria Participants will be withdrawn from the study if they develop any condition (decompensation, cardiovascular event, fracture, or others) that contraindicates or prevents continuation of the prescribed physical exercise intervention.

Withdrawn participants will not be replaced. No follow-up will be performed once the participant has discontinued the intervention.

Participant dropout will be considered in cases of:

• inability to contact the participant for the scheduled follow-up video calls during months 1-2 (intervention group),
• failure to attend the in-person visit at months 3-4,
• voluntary decision to discontinue participation.

Adverse Event Monitoring The VIVIFRAIL program is a physical exercise intervention whose safety has already been demonstrated in previous studies. The exercises are simple and easy to understand, and participants will receive training before discharge regarding their correct performance.

Participants will receive brochures ("VIVIFRAIL passports"; see Annex 3) where they will record potential side effects such as pain, fatigue, or dyspnea during exercise sessions. In case of symptom onset during exercise, patients/caregivers will be advised to contact the research team using the telephone number/email provided before discharge.

Participants will also be informed of potential adverse effects when receiving the informed consent form.

• baseline Barthel Index ≥60
• ability to communicate, ambulate, and complete the exercise program

Data obtained through this study may be provided to qualified researchers with academic interest.