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A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement
Published on: February 22, 2022
Effect of high-intensity interval training on cardiovascular function, VO2max, and muscular force
Todd A Astorino1, Ryan P Allen, Daniel W Roberson
1Department of Kinesiology, California State University, San Marcos, California, USA. astorino@csusm.edu
Journal of Strength and Conditioning Research
|December 29, 2011
Summary
Short-term high-intensity interval training (HIIT) significantly improved cardiorespiratory fitness, including maximal oxygen uptake (VO2max) and oxygen pulse, in active adults. However, HIIT did not impact resting blood pressure, heart rate, or muscular force production.
Area of Science:
- Exercise Physiology
- Sports Science
- Cardiovascular Health
Background:
- High-intensity interval training (HIIT) is a time-efficient exercise strategy.
- Understanding HIIT's impact on various physiological markers is crucial for optimizing training protocols.
- Previous research indicates HIIT benefits cardiorespiratory fitness, but effects on muscular force and resting hemodynamics require further investigation.
Purpose of the Study:
- To investigate the effects of a 2- to 3-week high-intensity interval training (HIIT) program on cardiovascular function, cardiorespiratory fitness, and muscular force in active young adults.
- To determine changes in maximal oxygen uptake (VO2max), oxygen pulse, power output, and voluntary force production following a short-term HIIT intervention.
Main Methods:
- Twenty active, healthy men and women (mean age 25.3 years) completed 6 sessions of HIIT over 2-3 weeks, involving repeated Wingate tests.
- A control group (N=9) underwent testing without the HIIT intervention.
- Measurements included resting blood pressure (BP), heart rate (HR), VO2max, body composition, oxygen (O2) pulse, power output, fatigue index, and knee extensor/flexor force production, assessed pre- and post-intervention.
Main Results:
- Significant improvements (p < 0.05) were observed in maximal oxygen uptake (VO2max), oxygen pulse, and Wingate-derived power output following HIIT.
- The degree of VO2max improvement correlated with baseline VO2max (r = -0.44) and the fatigue index (r = 0.50).
- No significant changes (p > 0.05) were found in resting BP, HR, or voluntary force production.
Conclusions:
- Short-term HIIT effectively enhances cardiorespiratory fitness, indicated by improvements in VO2max and oxygen pulse.
- HIIT also boosts power output, as measured by the Wingate test.
- The study suggests that while HIIT improves aerobic capacity and power, it does not significantly alter resting cardiovascular parameters or muscular strength in this population over a short duration.
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