High-Intensity Intervallic Exercise (HIIE) Is Superior to Isocaloric Moderate-Intensity Continuous Exercise (MICE) at Reducing Postprandial Hyperglycemia.
Level 2 - randomized trial
Randomized crossover trial
PubMed 39661748 · doi:10.1249/MSS.0000000000003625
What was done
Nineteen healthy physically active individuals (21% women) completed three trials in randomized order: (1) high-intensity interval exercise (HIIE; 5 × 4 min cycling at 83 ± 9% VO2max with active recovery at 53 ± 8%, total 50 min), (2) moderate-intensity continuous exercise (MICE; 50 min cycling at 65 ± 8% VO2max), and (3) a resting control trial. Each trial was followed by an oral glucose tolerance test (OGTT; 74 g glucose with 1 g [13C]-glucose tracer). Plasma glucose and insulin levels, glucose kinetics ([6,6-2H2]-glucose infusion), Matsuda insulin sensitivity index, energy expenditure, and carbohydrate oxidation were measured.
What was found
Energy expenditure during exercise was similar between HIIE and MICE (548 ± 131 vs 560 ± 125 kcal; P = 0.340). HIIE yielded higher carbohydrate oxidation, plasma glucose, and glucose appearance rates (Ra) during exercise compared to MICE (Ra glucose: 34.3 ± 9.8 vs 28.9 ± 6.8 µmol·kg⁻¹·min⁻¹; P = 0.021). During the OGTT, HIIE resulted in lower glucose and insulin concentrations and higher insulin sensitivity than control (Matsuda index: 12.4 ± 4.7 vs 10.8 ± 4.7 au; P = 0.007). Exercise delayed [13C]-glucose blood appearance (P = 0.023), and early OGTT glucose clearance rates were higher in HIIE versus control (7.1 ± 3.1 vs 5.5 ± 3.0 mL·kg⁻¹·min⁻¹; P = 0.015).
Why it matters
This study shows that exercise intensity modulates postprandial glucose regulation independently of total energy expenditure, with interval exercise enhancing glucose clearance and splanchnic glucose retention.
Limits
The study had a small sample size (n = 19) predominantly composed of males (79%) who were healthy and active, limiting direct generalizability to sedentary individuals or populations with diabetes. Only acute responses to a single exercise bout and liquid glucose challenge were evaluated.
Cited by
- supports When exercise volume is equated, high-intensity interval training yields greater improvements in glucose regulation than continuous low- to moderate-intensity training.