Purpose
We aimed to investigate differences between high-intensity interval exercise [HIIE; included high-intensity interval training (HIIT) and sprint interval training (SIT)] and moderate-intensity continuous training (MICT) on physical fitness, body composition, blood pressure, blood lipids, insulin and glucose metabolism, inflammation, and endothelial function.
Methods
Differences between HIIE and MICT were summarized using a random-effects meta-analysis on the effect size (Cohen’s d). A meta-regression was conducted using subgroups: population, age, training duration, men ratio, exercise type, baseline values (clinical relevant ranges), and type of HIIE. Studies were included if at least one of the following outcomes were reported: maximal oxygen uptake (V[Combining Dot Above]O2max), flow-mediated dilation (FMD), body mass index (BMI), body mass, % body fat, systolic and diastolic blood pressure, high-density lipoprotein (HDL), low-density lipoprotein (LDL), triglycerides, total cholesterol, C-reactive protein (CRP), fasting glucose and insulin, glycated hemoglobin (HbA1c), and insulin resistance (HOMA-IR). A total of 55 studies were included.
Results
Overall, HIIE was superior to MICT in improving V[Combining Dot Above]O2max (d=0.40, p<0.001), and FMD (d=0.54, p<0.05). Oppositely, MICT was superior to HIIE in improving HbA1c (d=-0.27, p<0.05). No differences were observed in BMI (d=-0.02), body mass (d=-0.05), % body fat (d=0.04), systolic (d=-0.04) and diastolic blood pressure (d=0.03), HDL (d=-0.05), LDL (d=0.08), triglycerides (d=0.03), total cholesterol (d=0.14), CRP (d=-0.11), fasting insulin (d=0.02), fasting glucose (d=0.02), and HOMA-IR (d=-0.04). Moderator analyses indicated the difference between HIIE and MICT was affected by different subgroups.
Conclusion
Overall, HIIE showed to be more effective in improving cardiovascular health and cardiorespiratory fitness, while MICT was superior in improving long-term glucose metabolism. In the process of personalized training counseling, health-enhancing effects of exercise training may be improved by considering the individual risk profiles.
