Abbreviations, Acronyms & Symbols

6MWT	= 6-minute walk test	METs	= Metabolic equivalent of task
CABG	= Coronary artery bypass grafting	MIP	= Maximal inspiratory pressure
CPAP	= Continuous positive airway pressure	MRC	= Medical Research Council
HF	= High frequency	NR	= Not reported
HR	= Heart rate	POD	= Postoperative day
HRV	= Heart rate variability	RR	= R-R intervals
ICU	= Intensive care unit	SpO2	= Saturation of peripheral oxygen
IMT	= Inspiratory muscle training	VO2	= Oxygen uptake
LF	= Low frequency