Patients will be recruited in the 4 participating sites and will sign the informed consent If they agree to participate. It is planned to include 32 patients with ovarian cancer on maintenance PARPi after response to first-line platinum-based chemotherapy in the study.

Patients included in the study will follow an online physical exercise program supervised by a physical exercise specialist in which they will perform up to 300 minutes of moderate-intensity aerobic exercise or up to 150 minutes of vigorous aerobic exercise and 2 strength sessions per week for 12 weeks (following World Health Organization (WHO) recommendations for cancer survivors).

In an initial nursing visit, patient's demographic data, epidemiological, clinical, biological and training-related variables, as well as fatigue, quality of life and mental health questionnaires will be obtained. The activity bracelet, blood pressure monitor, elastic bands set, and a document of exercise compliance will also be provided to the patient. If necessary, a local gym registration will be provided.

The program will include 12 stages. Each stage will correspond to one week, with 3 to 5 sessions per week containing cardiorespiratory, strength and flexibility training tasks. Where necessary, joint mobility and neuromotor work will be included. The exercise prescription parameters will be adapted to the patient's clinical history (intensity, frequency, duration, training system, progression) and patient's interest if the clinical condition allows it. Throughout the program, periodic records of symptoms, effort and intensity scales, blood pressure, heart rate, as well as the patient's emotional state will be requested.

After the registration process, a tutor (physiotherapist) will be assigned to the patient. An initial assessment is scheduled to analyze the clinical situation and to design the program. During this first consultation, the patient will be introduced to the platform and will take a preliminary course on basic training for control and monitoring of the program.

During the course, questions can be asked to the tutor via the platform chat. Once the patient reports the completion of a stage, the subsequent content will be released.

The tutor will supervise and follow up through scheduled video calls (one every 15 days of training); as well as through the message system.

All patients will have a period of 12 weeks to complete their program. The tutor will maintain constant communication with the responsible physician.

Participants will also receive an initial and mid-program online nutritional assessment with personalized health and dietary recommendations.

A final nurse visit will be made at the end of the program and after 3 months of follow up to evaluate whether the patient maintains the healthy habits acquired during the 12 weeks of the program.

Inclusion Criteria:

1. Women ≥ 18 years old.

2. High grade serous or endometrioid ovarian, primary peritoneal or fallopian tube cancer.

3. Provide written informed consent.

4. Eastern Cooperative Oncology Group (ECOG) performance status 0-1.

5. Stage III-IV according to International Federation of Gynecology and Obstetrics (FIGO) staging system.

6. Life expectancy of ≥ 6 months.

7. Maintenance treatment with PARPi after response to first-line platinum-based chemotherapy, initiated at least 4 weeks prior to the informed consent signature.

8. Patient is clinically stable and anticipate remaining on therapy for the duration of the exercise program.

9. Patient is willing to provide a tumor tissue sample either collected from a prior biopsy or cytoreductive/debulking surgery occurring at any time since diagnosis, if available.

10. Patients with sufficient digital capacity at the investigator's discretion.

11. Ability and willingness to comply with the study protocol for the duration of the study and with follow-up procedures.

12. Have adequate baseline function within 28 days of enrollment:

    • Platelets ≥ 100 × 109/L

    • Absolute neutrophil count (ANC) ≥ 1500/mm3

    • Hemoglobin ≥ 9 g/dL or 5.6 mmol/L

    • Aspartate transaminase and alanine transaminase ≤2.5 × upper limit of normal (ULN), <5 × ULN in patients with known liver metastases

    • Serum total bilirubin ≤ 1.5 × ULN

      • 1.5-3.0 × ULN may be included with appropriate starting dose adjustment to 200 mg niraparib daily.

    • Creatinine <1.5 × ULN or estimated glomerular filtration rate (GFR) ≥50 ml/min by Cockcroft-Gault.

Exclusion Criteria:

1. Women with diagnosis of recurrent ovarian cancer.

2. Serous, non-healing wound, ulcer or bone fracture.

3. Active bleeding or pathologic conditions that carry high risk of bleeding, such as known bleeding disorder or coagulopathy.

4. Central nervous system disease.

5. History of significant cardiovascular disease within 6 months prior to enrollment:

   • History of NCI CTCAE v5.0 Grade ≥ 3 symptomatic congestive heart failure (CHF) or New York Heart Association (NYHA) Class ≥ II.
   • High-risk uncontrolled arrhythmias (i.e., atrial tachycardia with a heart rate ≥100/min at rest, significant ventricular arrhythmia [ventricular tachycardia], or higher-grade atrioventricular [AV]-block, such as second-degree AV-block Type 2 [Mobitz II] or third-degree AV-block).
   • Myocardial infarction or ischemic disease,
   • Clinically significant valvular heart disease.
   • Ischemic or hemorrhagic stroke,
   • Thromboembolic events,
   • Peripheral vascular disease,
   • Aortic aneurysm, aortic dissection.

6. Pre-existing uncontrolled hypertension as documented by two baseline blood pressure readings taken at least five minutes apart, defined as systolic BP ≥ 140 or diastolic BP ≥ 90 mm Hg pressure.

7. Patient requires recurrent (≥ 1 per month) fluid drainage (eg, paracentesis, thoracocentesis, pericardiocentesis) or patient requires fluid drainage of ≥ 500 mL within 4 weeks of the expected date of exercise initiation.

8. Active infection and/or fever ≥ 38,5ºC within 7 days prior to initiation of the program requiring systemic antibiotics (excluding uncomplicated urinary tract infection).

9. Patient has undergone any major surgical procedure within 3 weeks prior to screening or is planned during the program.

10. Known QT interval corrected by the Fridericia Correction Formula values of >470msec; patient who is known to have congenital prolonged QT syndromes; or patient who is on medication known to cause prolonged QT interval on ECG.

11. Patient had received a transfusion (platelets or red blood cells) or colony-stimulating factors (e.g., granulocyte macrophage colony-stimulating factor or recombinant erythropoietin) within 4 weeks before the exercise initiation.

12. Patient has underlying chronic lung disease, chronic obstructive pulmonary disease, metastatic lung disease, pleural effusions or pneumonitis.

13. Extensive non-oncological bone disease or presence of long-bones metastases or other symptomatic bone metastatic disease.

14. Significant peripheral sensory or motor neuropathy that could interfere with exercise program at investigator discretion.

15. Patient who are pregnant, breastfeeding, or expecting to conceive children during program.