 Protocol for the intervention group The EFICAR group differs from the control group only in terms of the exercise programme, which has two phases. The exercise programme is a combination of high-intensity interval training and muscular strength training. It has been demonstrated that high intensity aerobic exercise leads to better aerobic and cardiovascular changes than lightmoderate exercise in patients with HF 1st PHASE 12 weeks, 3 sessionsweek: for the first three months, patients carry out a progressive exercise programme of 36 sessions under the supervision of the nurse, starting at low intensity first month and increasing it month by month. 