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

Abstract

All-out sprint interval training (SIT) is speculated to be an effective and time-efficient training regimen to improve the performance of aerobic and anaerobic exercises. SIT under hypoxia causes greater improvements in anaerobic exercise performance compared with that under normoxia. The change in oxygen concentration may affect SIT-induced performance adaptations. In this study, we aimed to investigate the effects of all-out SIT under hyperoxia on the performance of aerobic and anaerobic exercises. Eighteen college male athletes were randomly assigned to either the normoxic sprint interval training (NST, n = 9) or hyperoxic (60% oxygen) sprint interval training (HST, n = 9) group and performed 3-week SIT (six sessions) consisting of four to six 30-sec all-out cycling sessions with 4-min passive rest. They performed maximal graded exercise, submaximal exercise, 90-sec maximal exercise, and acute SIT tests on a cycle ergometer before and after the 3-week intervention to evaluate the performance of aerobic and anaerobic exercises. Maximal oxygen uptake significantly improved in both groups. However, blood lactate curve during submaximal exercise test significantly improved only in the HST group. The accumulated oxygen deficit (AOD) during 90-sec maximal exercise test significantly increased only in the NST group. The average values of mean power outputs over four bouts during the acute SIT test significantly improved only in the NST group. These findings suggest that all-out SIT might induce greater improvement in aerobic exercise performance (blood lactate curve) but impair SIT-induced enhancements in anaerobic exercise performance (AOD and mean power output).

Keywords: Accumulated oxygen deficit; hyperoxic training; lactate curve; trained athletes.

Figure 1

Typical example of changes in SpO₂ during six repeated bouts of sprint exercise under normoxia and hyperoxia obtained from the same subject.

Figure 2

Training power outputs throughout the 3‐week all‐out sprint interval training. NST, normoxic sprint interval training (n = 9); HST, hyperoxic sprint interval training (n = 9). Values are presented as means ± SE.

Figure 3

Maximal oxygen uptake (${\dot{\text{V}}\text{O}}_{2}max$) and workload before (pre) and after (post) 3 weeks of all‐out sprint interval training. NST, normoxic sprint interval training (n = 9); HST, hyperoxic sprint interval training (n = 9). Values are presented as means ± SE. *P < 0.05 versus pre.

Figure 4

Blood lactate curve during submaximal intermittent incremental cycling test before (pre) and after (post) 3 weeks of all‐out sprint interval training. NST, normoxic sprint interval training (n = 9); HST, hyperoxic sprint interval training (n = 9). Values are presented as means ± SE. *P < 0.05 versus pre.

Figure 5

Percent changes in AOD and %AOD during 90‐sec maximal cycling test before (pre) and after (post) 3 weeks of all‐out sprint interval training. NST, normoxic sprint interval training (n = 9); HST, hyperoxic sprint interval training (n = 9). Values are presented as means ± SE. *P < 0.05 between the NST and HST.

Figure 6

Percent changes in average mean power outputs during acute sprint interval exercise test before (pre) and after (post) 3 weeks of all‐out sprint interval training. NST, normoxic sprint interval training (n = 9); HST, hyperoxic sprint interval training (n = 9). Values are presented as means ± SE. *P < 0.05 between the NST and HST.

Figure 7

Serum derivatives of reactive oxygen metabolites (d‐ROMs), biological antioxidant potential (BAP), and BAP/d‐ROMs ratio before (pre) and after (post) 3 weeks of all‐out sprint interval training. NST, normoxic sprint interval training (n = 9); HST, hyperoxic sprint interval training (n = 9). Values are presented as means ± SE. *P < 0.05 versus pre.