Overview

The main objective is to evaluate in hemodialysis patients the effects of two intradialytic rehabilitation programs based on physical exercise, with or without the application of blood flow restriction, on myocardial stunning and morpho-functional cardiac remodelling, compared with usual care (i.e., dialysis without exercise). In addition, the investigators will also assess the acute effects (i.e., a single session for each condition) of physical exercise, with or without blood flow restriction, on myocardial stunning at the end of dialysis.

In comparison with a conventional exercise program, the combination of physical exercise with blood flow restriction, which synergistically and additively activates intramuscular signalling pathways related to both exercise and ischaemia, is hypothesised to result in:

1. A greater intradialytic cardioprotection, as demonstrated by a greater reduction in myocardial stunning at the end of dialysis (both in acute and chronic applications), with underlying mechanisms involving systemic and neuro-humoral pathways;
2. Significant improvements in morpho-functional cardiac remodelling, attenuation of arrhythmic disturbances, and enhancement of aerobic capacity, muscle strength, and muscle mass-effects not observed with exercise alone without blood flow restriction, considering the low exercise intensity used in the current rehabilitation program (chronic application only).

This is a three-arm randomised clinical trial with parallel groups: standard hemodialysis (HD-CONTChro), a rehabilitation program with intradialytic exercise without vascular occlusion (HD-EXChro), and a rehabilitation program with intradialytic exercise with vascular occlusion (HD-BFREChro), with a 1:1:1 allocation ratio.

To investigate the acute effects of the interventions, all patients will undergo, in a randomized order, one session of each of the three dialysis modalities-standard hemodialysis (HD-CONTacute), hemodialysis with exercise without vascular restriction (HD-EXacute), and hemodialysis with exercise with vascular restriction (HD-BFREacute)-prior to initiation of the chronic phase of the study.

Eligibility

Inclusion Criteria:

• Patients aged between 20 and 79 years.
• Patients on hemodialysis for more than 3 months.
• No engagement in regular exercise outside of dialysis.
• No prior exposure to intradialytic exercise within the past six months.
• No medical contraindications to physical activity.
• Life expectancy greater than 6 months.
• Patients with relative good echogenicity

Exclusion Criteria:

• Patient is participating in another Category I interventional study, or has participated in another interventional study within the past 3 months
• The patient is in an exclusion period determined by a previous study
• The patient is under legal protection or under guardianship or curatorship It turns out to be impossible to give the patient informed information, or the patient refuses to sign the consent
• Pregnant, parturient or breastfeeding patient
• Patients with unstable coronary artery disease.
• Patients with peripheral artery disease (stage III or IV) in the lower limbs.
• Patients with limb amputation.
• Patients with musculoskeletal disorders impairing exercise.
• Presence of a pacemaker, cardiac stimulation device, or implantable cardioverter defibrillator (ICD).
• History of heart transplant.
• Patients with uncontrolled hypertension.
• Refractory anemia.
• Patients stratified as high risk for deep venous thrombosis