Effects of pre-term birth on the cardio-respiratory responses to hypoxic exercise in children

Pre-term birth is associated with numerous cardio-respiratory sequelae in children. Whether these impairments impact the responses to exercise in normoxia or hypoxia remains to be established. Fourteen prematurely-born (PREM) (Mean ± SDgestational age 29 ± 2 weeksage 9.5 ± 0.3 years), and 15 full-term children (CONT) (gestational age 39 ± 1 weeksage 9.7 ± 0.9 years), underwent incremental exercise tests to exhaustion in normoxia (FiO$_2$ = 20.9%) and normobaric hypoxia (FiO$_2$ = 13.2%) on a cycle ergometer. Cardio-respiratory variables were measured throughout. Peak power output was higher in normoxia than hypoxia (103 ± 17 vs. 77 ± 18 Wp 0.999, respectively). In conclusion, premature birth does not appear to exacerbate the negative effect of hypoxia on exercise capacity in children. Further research is warranted to identify whether prematurity elicits a protective effect, and to clarify the potential underlying mechanisms