Sprint Intervals Edge Out Steady Moderate Training in Meta-Analysis of 44 Trials

Sprint interval training may offer modest advantages over moderate-intensity continuous training for a small number of physiological outcomes, but it is not universally superior, according to a systematic review and meta-analysis published in BMC Sports Science, Medicine and Rehabilitation. The analysis pooled 44 randomized controlled trials involving 1,034 healthy adults and compared the long-term effects of the two training modalities on cardiorespiratory fitness, metabolic health markers and exercise performance.

The review followed the PRISMA statement and systematically searched the PubMed, Web of Science, Embase and CNKI databases up to November 14, 2025. Only randomized controlled trials comparing the long-term effects of sprint interval training and moderate-intensity continuous training were included. The researchers calculated standardized mean differences using Hedges’ g within a three-level meta-analysis framework, and conducted subgroup analyses and meta-regressions to explore potential moderating factors, including participant characteristics such as sex, age and training status, and training prescription variables such as frequency, intervention duration, recovery interval, sprint duration, session volume and total training time.

Across the pooled trials, statistically significant between-group differences emerged for three outcomes. Sprint interval training produced greater improvements in relative maximal oxygen uptake, with an effect size of g = 0.23 (95% CI 0.07 to 0.38), and in maximal heart rate, with g = 0.46 (95% CI 0.11 to 0.80). For total cholesterol, the direction of the effect favored sprint training, with g = −0.59 (95% CI −1.12 to −0.05). No statistically significant between-group differences were identified for the other measured outcomes, meaning the two training modalities performed comparably across most endpoints examined.

The authors emphasize that the magnitude of these differences is generally small, and that wide prediction intervals indicate substantial uncertainty in how well the findings generalize to new settings and populations. In other words, while the pooled estimates favor sprint interval training for relative VO2max, maximal heart rate and total cholesterol, the true effects in individual studies or individuals could vary considerably around those averages.

Exploratory subgroup analyses suggested that sex, training status, exercise modality and per-session volume may influence effect sizes for specific outcomes. However, the researchers caution that these findings should be interpreted cautiously, because the number of studies in some of the subgroup analyses was limited. Moderating analyses of this kind are hypothesis-generating rather than confirmatory, and the reported patterns do not establish that any particular subgroup definitively benefits more from one training modality.

The practical takeaway offered by the authors is that sprint interval training may be a time-efficient option for improving selected physiological outcomes, since it can achieve comparable or modestly greater effects than moderate-intensity continuous training on relative VO2max, maximal heart rate and total cholesterol. At the same time, they state that current evidence does not support considering sprint interval training universally superior to moderate-intensity continuous training, and that its application should be tailored to individual characteristics and training objectives.

The study was registered as CRD420251231005 and is published as an open-access article. As an analysis of previously conducted randomized trials in healthy adults, its conclusions describe pooled average effects across heterogeneous study populations and protocols; the authors’ own framing underscores that the small effect sizes and wide prediction intervals warrant caution when applying the results to individual training decisions.

Subject of Research: Comparative effects of sprint interval training versus moderate-intensity continuous training in healthy adults

Article Title: Effects of sprint interval training versus moderate-intensity continuous training on physiological adaptations and exercise performance in healthy adults: a systematic review and meta-analysis

Article References: Li, Y., Xu, H., Wang, J., & Bi, Z. (2026). Effects of sprint interval training versus moderate-intensity continuous training on physiological adaptations and exercise performance in healthy adults: a systematic review and meta-analysis. BMC Sports Science, Medicine and Rehabilitation. https://doi.org/10.1186/s13102-026-02176-9

Image Credits: AI Generated

DOI: 10.1186/s13102-026-02176-9

Keywords: sprint interval training, moderate-intensity continuous training, meta-analysis, systematic review, VO2max, cardiorespiratory fitness, total cholesterol, exercise performance, healthy adults, randomized controlled trials, HIIT, training prescription