TABLE 1

Summary of the effects of short-term oxygen compared to air in randomised trials

	Outcome	Studies	Participants	Estimate	Study design
During exercise	Borg dyspnoea score	2	27	−0.06 (−0.24–0.13) units lower with oxygen	Randomised, placebo-controlled, crossover
	Peak work on CPET	1	7	17 (10.60–23.40) W higher with oxygen	Randomised, placebo-controlled, crossover
	V_O₂peak on CPET	1	7	Mean 1.58 L·min⁻¹ on oxygen versus 1.32 L·min⁻¹ on air, p<0.05	Randomised, placebo-controlled, crossover
	Cycle endurance time	1	16	6 (3.64–8.26) min longer with oxygen	Randomised, placebo-controlled, crossover
	6MWD	1	20	13 (−24–50) m further with oxygen	Randomised, placebo-controlled, crossover
At rest	100 mm VAS	1	10	Mean 30.2 mm on oxygen versus 48.1 mm on air, p<0.05	Randomised, placebo-controlled, crossover

Data are presented as n or mean (95% CI), unless otherwise stated. CPET: cardiopulmonary exercise test; V_O₂peak: peak oxygen uptake; 6MWD: 6 min walk distance; VAS: visual analogue scale.