BACKGROUND AND PURPOSE: Cardiac surgery enhances cardiovascular disease (CVD) patient survival rates, and the fast-track protocol can reduce complications, hospital length of stay (HLOS) and associated costs. However, there is no evidence on the effectiveness of unsupervised physiotherapy programmes in reducing HLOS and postoperative pulmonary complications in patients undergoing fast-track surgery. The study aimed to determine if a pre-surgical respiratory programme reduces intensive care unit length of stay (ICULOS) and HLOS patients undergoing fast-track surgery, and its effects on post-operative complications and healthcare costs. METHODS: This was a retrospective observational cohort study. The patients were divided into two groups: those who followed the exercise programme (pre-hab group) and those who did not (no pre-hab group). The study analysed the mean of ICULOS and HLOS for each group, recorded post-operative complications, and calculated healthcare costs using the Spanish Ministry of Health cost tables. RESULTS: A total of 418 patients participated in the study with a mean age of 70.44 (10.87) years. The study found significant differences in HLOS (p = 0.001) and ICULOS (p = 0.003) between groups. Pre-hab HLOS was 232.8 (221.3) hours in the hospital, whereas no pre-hab LOS increased to 315.1 (277.9) hours. Pre-hab ICULOS was 82.0 (129.8) hours when No pre-hab ICULOS accounted 120.2 (190.3) hours. This reduction in hospital admissions resulted in savings of €356,107.16 in average healthcare costs for the pre-hab group. Mortality risk (p = 0.034) was also reduced in the pre-hab group (17.7% vs. 26.65% in the no pre-hab group). DISCUSSION: An unsupervised home-based respiratory programme reduces hospital and ICU stay, healthcare costs, post-surgical pulmonary complications, and mortality risk. The clinical application of an unsupervised home-based pre-habilitation programme, focussing on ventilatory exercises and costal expansion techniques, has proven effective in enhancing patient recovery post-cardiac surgery, offering significant healthcare cost savings, and reducing the burden on hospital resources.