Is high-intensity interval training more effective on improving cardiometabolic risk and aerobic capacity than other forms of exercise in overweight and obese youth? A meta-analysis.

BACKGROUND The scientific interest in high-intensity interval training (HIIT) has greatly increased during recent years. OBJECTIVE The objective of this meta-analysis was to determine the effectiveness of HIIT interventions on cardio-metabolic risk factors and aerobic capacity in overweight and obese youth, in comparison with other forms of exercise. DATA SOURCES A computerized search was made using seven databases. STUDY ELIGIBILITY CRITERIA The analysis was restricted to studies that examined the effect of HIIT interventions on cardio-metabolic and/or aerobic capacity in pediatric obesity (6-17 years old). PARTICIPANTS AND INTERVENTIONS Nine studies using HIIT interventions were selected (n = 274). STUDY APPRAISAL AND SYNTHESIS METHODS Standarized mean difference (SMD) and 95% confidence intervals were calculated. The DerSimonian-Laird approach was used. RESULTS HIIT interventions (4-12 week duration) produced larger decreases in systolic blood pressure (SMD = 0.39; -3.63 mmHg) and greater increases in maximum oxygen uptake (SMD = 0.59; 1.92 ml/kg/min) than other forms of exercise. Also, type of comparison exercise group and duration of study were moderators. CONCLUSIONS HIIT could be considered a more effective and time-efficient intervention for improving blood pressure and aerobic capacity levels in obese youth in comparison to other types of exercise. © 2016 World Obesity.