Effects of all-out sprint interval training under hyperoxia on exercise performance

Area of Science:

• Exercise Physiology
• Sports Science
• Environmental Physiology

Background:

• Sprint interval training (SIT) is a time-efficient method for improving exercise performance.
• Hypoxic SIT enhances anaerobic performance more than normoxic SIT.
• The impact of hyperoxia on SIT adaptations requires further investigation.

Purpose of the Study:

• To investigate the effects of all-out SIT under hyperoxia on aerobic and anaerobic exercise performance.
• To compare hyperoxic SIT (HST) with normoxic SIT (NST) in college male athletes.

Main Methods:

• Eighteen male athletes were randomized into normoxic SIT (NST) or hyperoxic SIT (HST, 60% oxygen) groups.
• Both groups underwent a 3-week SIT program (6 sessions) with 4-6 repetitions of 30-sec all-out cycling and 4-min rest.
• Aerobic and anaerobic exercise performance were assessed using maximal graded exercise, submaximal exercise, 90-sec maximal exercise, and acute SIT tests.

Main Results:

• Maximal oxygen uptake improved in both HST and NST groups.
• Blood lactate curve during submaximal exercise improved significantly only in the HST group.
• Accumulated oxygen deficit and mean power output during SIT improved significantly only in the NST group.

Conclusions:

• All-out SIT under hyperoxia may enhance aerobic performance (lactate curve) but potentially impair anaerobic adaptations.
• Normoxic SIT might be more effective for improving anaerobic exercise performance metrics like accumulated oxygen deficit and mean power output.