Karabiyik, HakanEser, Mustafa CanGuler, OzkanYasli, Burak CaglarErtetik, GoktugSisman, AysegulKoz, MitatGabrys, TomaszPilis, KarolKarayigit, Raci2023-04-062023-04-062021-04-091660-4601https://hdl.handle.net/20.500.12597/3399Sprint interval training (SIT) is a concept that has been shown to enhance aerobic-anaerobic training adaptations and induce larger effects in hypoxia. The purpose of this study was to examine the effects of 4 weeks of SIT with 15 or 30 s in hypoxia on aerobic, anaerobic performance and critical power (CP). A total of 32 male team players were divided into four groups: SIT with 15 s at FiO: 0.209 (15 N); FiO: 0.135 (15 H); SIT with 30 s at FiO: 0.209 (30 N); and FiO: 0.135 (30 H). VO did not significantly increase, however time-to-exhaustion (TTE) was found to be significantly longer in the post test compared to pre test ( = 0.001) with no difference between groups ( = 0.86). Mean power (MPw.kg) after repeated wingate tests was significantly higher compared to pre training in all groups ( = 0.001) with no difference between groups ( = 0.66). Similarly, CP was increased in all groups with 4 weeks of SIT ( = 0.001) with no difference between groups ( = 0.82). This study showed that 4 weeks of SIT with 15 and 30 s sprint bouts in normoxia or hypoxia did not increased VO in trained athletes. However, anerobic performance and CP can be increased with 4 weeks of SIT both in normoxia or hypoxia with 15 or 30 s of sprint durations.enHIITchronic trainingnormobaric hypoxiasprint durationteam athletesJournal Article10.3390/ijerph1808397633918866