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Published on: January 28, 2020
Decreasing Power Output Increases Aerobic Contribution During Low-Volume Severe-Intensity Intermittent Exercise
Felipe D Lisbôa1, Amadeo F Salvador, João A G Raimundo
1Human Performance Research Group, College of Health and Sport Science, Santa Catarina State University, Florianópolis, Brazil.
Decreasing power output (DPO) intermittent exercise protocols increase time spent at high percentages of maximal oxygen uptake (V[Combining Dot Above]O2max). This protocol enhances aerobic demand more effectively than constant power output (CPO) exercise.
Area of Science:
- Exercise Physiology
- Sports Science
- Cardiovascular Adaptation
Background:
- High-intensity interval training (HIIT) at various intensities yields similar adaptations to sprint interval training.
- Understanding exercise protocols that maximize aerobic demand is crucial for training optimization.
Purpose of the Study:
- To investigate time to reach 95% of maximal oxygen uptake (t95V[Combining Dot Above]O2max) during two severe-intensity intermittent exercise protocols.
- To identify an exercise protocol that reduces the time required to elicit higher aerobic demand.
Main Methods:
- Eight active men completed an incremental test, critical power (CP) determination, and highest intensity/lowest duration (IHIGH/TLOW) for V[Combining Dot Above]O2max attainment.
- Participants underwent randomized constant power output (CPO) and decreasing power output (DPO) sessions at IHIGH.
Main Results:
- Time to exhaustion was significantly longer in the DPO protocol (371 ± 57s) compared to CPO (225 ± 33s).
- t95V[Combining Dot Above]O2max was substantially higher in DPO (186 ± 72s) versus CPO (76 ± 49s).
- Total oxygen consumption was greater during DPO (29 ± 4L) compared to CPO (17 ± 3L).
Conclusions:
- The decreasing power output (DPO) intermittent exercise protocol increases the duration spent at high percentages of V[Combining Dot Above]O2max.
- DPO protocols may be more effective than CPO protocols in enhancing aerobic demand during severe-intensity exercise.
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