Effective rehabilitation strategies are paramount to improve physiological and psychological health in pulmonary disease. The aim of this thesis was to investigate traditional and alternative pulmonary rehabilitation strategies in those with chronic respiratory disease. Chapter Four found that traditional pulmonary rehabilitation (PR) was physiologically and psychologically effective, regardless of respiratory disease, with socioeconomic status being a key determinant of adherence. Chapter Five investigated the feasibility and acceptability of IMT. Children aged 10.8 ± 0.8 years with Cystic Fibrosis (CF) enjoyed the IMT intervention, perceiving improvements in their physical ability and psychosocial health. The care team highlighted that future interventions needed to be longer and to monitor engagement and adherence. Chapter Six assessed the effectiveness of an alternative rehabilitation strategy, using a four-week inspiratory muscle training (IMT) intervention, on lung function and heart rate variability in children with CF aged 10.8 ± 1.1 years. There were significant and clinically meaningful increases in respiratory muscle strength, a clinically meaningful decrease in sympathetic modulation, and decreases in respiratory symptoms. Subsequently, utilising the formative, physiological and psychological findings derived from Chapters Five and Six, an eight-week IMT intervention with live biofeedback, performed at 80% maximal inspiratory pressure, three times a week was implemented, with an eight-week optional IMT top-up. Overall, Chapter Seven found that eight weeks of IMT elicited significant increases in respiratory muscle strength, aerobic capacity and in CF-specific questionnaire domains in children (11.0 ± 2.2 years) with CF, which were maintained following the eight-week top-up period. Chapter Eight demonstrated significant improvements in inspiratory muscle strength and endurance after eight weeks, with sustained improvements in physiological health after 16-weeks in adults with bronchiectasis (64.5 ± 10.3 years). CF and bronchiectasis participants demonstrated high levels of adherence and reported competency and autonomy. Overall, IMT may be an effective and feasible alternative to pulmonary rehabilitation.