Cardiovascular diseases (CVD) are the main cause of morbidity and mortality in the world, being responsible for 17.9 million deaths annually, according to the World Heart Federation (WHF), which represents a significant social and health cost both due to direct expenses derived from admissions and diagnostic-therapeutic methods, as well as indirect expenses secondary to work incapacity, disability and loss of autonomy that this generates. Although advanced diagnostic and therapeutic techniques have been incorporated in recent years in the acute phase of ischemic heart disease, interventions during hospitalization and after hospital discharge remain insufficient in terms of secondary prevention, a paradoxical fact, since increasingly, the available evidence, as well as the recommendation guidelines, focus on the modification of lifestyle habits and control of cardiovascular risk factors (CVRF), fundamental pillars of cardiac rehabilitation programs (PRC) as a preventive measure both in the appearance of new adverse events and in the reduction of disease progression and improvement of the functional capacity of the patient. Cardiac rehabilitation (CR) was defined by the World Health Organization (WHO) in the 1960s as "the set of activities necessary to ensure that heart patients have an optimal physical, mental and social condition, allowing them to occupy, by their own means, as normal a place as possible in society." The scientific evidence is more than consistent regarding the benefits that multidisciplinary CRP provides in terms of cardiovascular mortality and quality of life (QoL) of our patients and how these results are maintained despite changes in patient characteristics and risk, or the incorporation of new pharmacological treatments. Therefore, if we deprive our patients of these therapies, we are indirectly acting negatively on their cardiovascular prognosis, especially within the field of ischemic heart disease, although it is increasingly being extended to other areas of Cardiology such as heart failure (HF), pulmonary hypertension (PH), valvular disease,7 etc. So much so that it is already included in the latest clinical practice guidelines of the main scientific societies at European and American level, establishing participation in a CR program after acute coronary syndrome or coronary revascularization and those patients with HF as a "level of recommendation I evidence A"

Currently, due to both the high percentage of patients with cardiovascular disease and the potential increase in sedentary lifestyle, with the geographical dispersion of some territories such as our integrated care area, it is vital to seek effective alternatives so that therapeutic exercise programs are carried out regularly, given that this sedentary attitude can increase the risk of mortality.40 This gives impetus to remote interventions such as telerehabilitation, as a useful paradigm to reduce this risk by being a set of technologies that has facilitated the application, monitoring and follow-up of physical exercise programming.

In today's technological era, the Internet of Things (IoT) paradigm has facilitated the incorporation of connected devices, such as smart tablets, motion sensors, activity trackers, and virtual reality systems, capable of monitoring physiological and behavioral variables in real time and acting on the data collected, thus enabling remote, personalized, and continuous interventions. These advances have begun to be used in healthcare and rehabilitation settings, with promising results.

In this way, an association has been evidenced between the home use of these technologies with moderate to high levels of participation in RCD and patient satisfaction with this modality; 46,47 with similar benefits in improving cardiovascular and psychological health, 48 which suggests that RCD with technological support is a viable option to monitor and even increase participation in the RC process, 46,48 especially for those patients who, due to their employment situation or geographical dispersion, do not have easy access to PRC. It should be taken into account that RCD may entail less medical supervision, control of physical exercise sessions with telemetry and monitoring, security and social interaction, but it is an alternative to achieve maintenance of physical activity levels in patients with CVD. 42 Some authors even recommend RCD in high-risk patients, given that the cardiovascular and psychological benefits that can be obtained by performing low-impact physical exercise at home are greater than the relative risk of an adverse event.

In this regard, several authors have shown that the implementation of home-based training protocols is safe and feasible for patients with low- and moderate-risk CVD; 50-53 with no significant difference in the relative risk of mortality between both CR modalities. 43 Other reviews reached similar conclusions without differentiating between total mortality, exercise capacity and QoL between the RCD and RCT groups. However, there was evidence of marginally higher levels of program completion by home-based participants.

One of the main weaknesses of the RCD is the lack of direct patient monitoring during the program. In this sense, the use of wearable devices overcomes this limitation, as it facilitates remote monitoring of patient activity, increasing accessibility to the RCP for people who would otherwise be unable to benefit from them. Furthermore, the use of these devices during the program contributes to improving adherence by allowing more precise monitoring of both exercise performance and various physiological variables that they record in real time.

The use of wearable devices in RCD programs improves patient adherence and allows for more effective monitoring of physical activity and physiological variables, resulting in greater program effectiveness compared to rehabilitation without remote monitoring.

The study will be conducted at the Virgen de la Luz Hospital in Cuenca, among patients with cardiac pathology described in the inclusion criteria, who will be enrolled in a cardiac rehabilitation program. The variables collected before and after the intervention will be analyzed and studied. Participants will be recruited throughout the project. Variables will be measured initially (inclusion in the program) and after the program ends (post-intervention).

The intervention will last 8 weeks (2 months). Both groups will receive the same exercise program, although the in-person group will attend the hospital 3 days a week for eight weeks, while the hybrid format will consist of 4 in-person sessions (every two weeks) supplemented with a home program until completing 3 sessions of the full program at home. Both groups will be monitored to measure adherence and ensure proper implementation of the program, as well as to adapt and personalize the exercise program and physical activity recommendations at all times. In this way, according to the classification of patients by number of steps (sedentary: < 5000 steps/day, not very active: 5000-7499 steps/day, somewhat active: 7500-9999 steps/day, active: 10000-12499 steps/day and very active: > 12499 steps/day),54 we will set the objective for the patient to be as active as possible, instructing them to try to increase the number of steps gradually, according to the recommendations of the guide for the prescription of physical exercise in patients with cardiovascular risk.

Likewise, patients will be monitored both with hospital telemetry, linked to the Ergoline training program, and with Polar H10 heart rate sensors during in-person sessions (in both groups), for subsequent analysis of electrocardiogram (ECG) signals.

The personalized exercise program for both groups will follow the following structure: warm-up (upper extremity mobilization, lower extremity and spine mobilization, for 10-15 minutes at an intensity of 1-2 on the modified Borg scale), strengthening exercises for large muscle groups (30-40% of 1RM for upper extremities and 50-60% of 1RM for lower extremities), abdominal muscle training, stretching, and relaxation or cool-down.

The program will be implemented with a respiratory muscle training program at 30-70% of the MIP (in the case of the inspiratory muscles) and the MEP (in the case of the expiratory muscles) in those patients whose respiratory pressure measurements have been less than 70% of the predicted value. To manage CVRF, they will receive health education sessions taught by a multidisciplinary team (urology, nursing, cardiology, physiotherapy, etc.). They will be given recommendations for daily physical activity (aerobic exercise) to complete the MIP, at an intensity of 60-85% of VO2 and 60-85% of the maximum heart rate (MHR) obtained by ergospirometry. This basic structure will be adapted for each patient with the goal of personalizing and maximizing the exercise dose (in terms of session duration, intensity, time, and type of exercise, following the FITT principle) based on the patient's progress and the level of physical activity reported by their activity trackers.

At the end of each week, personalized recommendations will be provided based on the analysis of data collected by wearable devices. These recommendations will be generated using adaptive recommendation systems that incorporate deep learning algorithms, allowing us to optimize the benefits of the cardiac rehabilitation program (CRP) and tailor it to each patient's individual needs, in line with the principles of personalized medicine. For patients in whom we also target weight loss as a control for CVRF due to obesity, we will encourage them to work daily at the point of maximum fat oxidation, or fatmax, to maximize the effect of PA on weight loss.

The exercise program will be implemented and reinforced by viewing the materials and videos recorded by the physical therapist, in order to achieve greater adherence to the program.

On the first day of the program, each patient will be given a Fitbit Inspire 3 activity tracker, which will be linked to a data-storage website to monitor each patient's program completion.

Inclusion Criteria:

1. Patients between the ages of 20 and 80.
2. Have suffered an acute event or have chronic cardiovascular disease with decreased/limited functional capacity.
3. Reside in the provinces of Cuenca, Toledo, or Albacete.
4. Willingness to participate voluntarily and acceptance of the conditions.
5. Must report the ability to access new technologies.

Exclusion Criteria:

1. Have a physical or mental condition that prevents participation.
2. Inability to adhere to the entire program, as reported in the initial consultation.
3. Are outside the age criteria defined above.

Both the researchers who manage the data and include it in the database, as well as those who analyze it, will not know the intervention that the participants have received.