- 2026-05-14
- Frontiers in endocrinology 17
Study Design
- Type
- Meta-Analysis
- Population
- adults with prediabetes
- Methods
- Systematic review and meta-analysis of intervention studies; PubMed, Embase, Web of Science, EBSCO, and the Cochrane Library were searched from inception to January 2026
Objective
To systematically review and meta-analyze intervention studies evaluating the effects of high-intensity interval training (HIIT) in adults with prediabetes, with a focus on glycemic control and cardiometabolic risk-related outcomes.Methods
PubMed, Embase, Web of Science, EBSCO, and the Cochrane Library were searched from inception to January 2026. Eligible studies included adults with prediabetes who participated in structured HIIT, with either a non-exercise control or an exercise comparator. Primary outcomes were glycemic measures, and secondary outcomes were cardiometabolic risk-related indicators. Change-from-baseline values were used preferentially for pooling effect sizes. Risk of bias was assessed using the Cochrane Risk of Bias 2 tool, heterogeneity using Cochran's Q and I², and certainty of evidence using GRADE. This review was registered in PROSPERO (CRD42024605154).Results
Thirteen intervention studies were included. Because of the limited number of eligible studies, no quantitative synthesis was performed for comparisons with non-exercise controls or across different HIIT protocols. Compared with HIIT, moderate-intensity continuous training (MICT) showed a small but statistically significant advantage for fasting blood glucose (FBG) (MD, 0.12 mmol/L, 95% CI 0.02 to 0.22; very low certainty). In contrast, HIIT showed significant advantages for 2-hour plasma glucose (2hPG) (MD, -0.16 mmol/L, 95% CI -0.28 to -0.04; low certainty) and cardiorespiratory fitness (SMD, 1.16, 95% CI 0.44 to 1.87; moderate certainty). No significant between-group difference was found for body mass index. Evidence for HbA1c, blood pressure, and lipid-related outcomes was limited.Conclusions
In adults with prediabetes, the effects of HIIT may be outcome-specific. HIIT may be more favorable for post-challenge glycemic control and cardiorespiratory fitness, whereas MICT may offer a modest advantage for fasting glucose. However, the certainty of evidence for glycemic outcomes was generally low to very low, and many included studies were short-term, suggesting that some observed effects may reflect short-term physiological responses rather than sustained clinical adaptations. Further high-quality trials with longer intervention periods are needed.