Related Experiment Video
Updated: Aug 5, 2026
08:27
A Real-World High-Intensity Interval Training Protocol for Cardiorespiratory Fitness Improvement
Published on: February 22, 2022
Effects of High-Intensity Interval Training on Body Composition and Cardiometabolic Health in Physically Inactive
Cunyu Lan1, Beibei Lei2, Juerui Li1
1Department of Sport Rehabilitation, School of Graduate Studies, Xi'an Physical Education University, Xi'an 710068, China.
Metabolites
|July 27, 2026
Summary
High-intensity interval training (HIIT) may improve cardiometabolic risk factors and body composition in inactive individuals. However, evidence quality is low, necessitating cautious interpretation and further research.
Area of Science:
- Cardiology
- Exercise Physiology
- Public Health
Background:
- Increasing physical activity is crucial for reducing cardiometabolic risk.
- Evidence on high-intensity interval training (HIIT) for inactive individuals is inconsistent.
- Extremely sedentary behavior poses unique challenges for exercise interventions.
Purpose of the Study:
- To evaluate the effects of HIIT on body composition and cardiometabolic outcomes.
- To compare HIIT with non-exercise control (CON) and moderate-intensity continuous training (MICT).
Main Methods:
- Systematic review and meta-analysis of 24 randomized trials (877 participants).
- Searched multiple databases (PubMed, Web of Science, Embase, Cochrane, Ovid, ClinicalTrials.gov).
- Assessed risk of bias (RoB 2), evidence certainty (GRADE), and robustness (leave-one-out analysis).
Main Results:
- HIIT reduced body weight, blood pressure, LDL, and total cholesterol compared to CON.
- HIIT increased maximal oxygen uptake (VO2max) compared to CON and MICT.
- Most findings had low or very low certainty of evidence and were sensitive to individual study removal.
Conclusions:
- HIIT shows potential for improving selected cardiometabolic outcomes, particularly VO2max.
- Low evidence certainty necessitates cautious interpretation of findings.
- Larger, high-quality trials are needed to establish HIIT's efficacy and optimal protocols for sedentary populations.
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