TABLE 1.

Electronic database search strategies.

Electronic database	Search stragety
	Mesh	Text word
Embase/pubmed/ cochrane/web of science	Breathing exercises	Exercise, breathing; respiratory muscle training; muscle training, respiratory; training, respiratory muscle
	Oxidative stress	Oxidative stresses; stress, oxidative; antioxidative stress; antioxidative stresses; stress, antioxidative; anti-oxidative stress; anti oxidative stress; anti-oxidative stresses; stress, anti-oxidative; oxidative damage; damage, oxidative; oxidative damages; oxidative stress injury; injury, oxidative stress; oxidative stress injuries; stress injury, oxidative; oxidative injury; injury, oxidative; oxidative injuries; oxidative cleavage; cleavage, oxidative; oxidative cleavages; oxidative dna damage; dna damage, oxidative; damage, oxidative dna; oxidative dna damages; dna oxidative damage; dna oxidative damages; damage, dna oxidative; oxidative damage, dna; oxidative and nitrosative stress; oxidative nitrative stress; nitrative stress, oxidative; oxidative nitrative stresses; stress, oxidative nitrative; nitro-oxidative stress; nitro oxidative stress; nitro-oxidative stresses; stress, nitro-oxidative; stresses, and nitro-oxidative
CNKI	[Subject: breathing exercise (accurate)] OR [Subject: breathing rehabilitation (accurate)] OR [Subject: inspiratory muscle training (accurate)] AND [Subject: oxidative stress (accurate)] OR [Subject: oxidation-antioxidation (accurate)] OR [Subject: oxidation reduction state (accurate)]
WANFANG	[Subject: (breathing exercise) or Subject: (breathing rehabilitation) or Subject: (inspiratory muscle training)] and [Subject: (oxidative stress) or Subject: (oxidation-antioxidation) or Subject: (oxidation reduction state)]