An acute bout of 4 × 4-min or 10 × 1-min HIIT improves β cell glucose sensitivity in postmenopausal females with type 2 diabetes: a secondary analysis.
Level 2 - randomized trial
Individual randomized crossover trial
PubMed 39694495 · doi:10.1152/japplphysiol.00777.2024
What was done
Thirteen postmenopausal females with type 2 diabetes (age 70 ± 5 years, BMI 32.4 ± 5.6 kg/m², HbA1c 6.7 ± 1.0%) participated in a semi-randomized crossover trial. Participants completed an initial resting control condition followed by two isocaloric high-intensity interval training protocols in randomized order separated by 2–4 days: 4 × 4-min HIIT (HIIT4) and 10 × 1-min HIIT (HIIT10). Beta-cell glucose sensitivity and insulin sensitivity indices (Matsuda index, OGIS, Stumvoll, and QUICKI) were assessed during a 2-hour mixed-meal tolerance test initiated 2 hours after rest or exercise.
What was found
Both exercise protocols significantly improved beta-cell glucose sensitivity relative to the resting control condition: - HIIT4 vs. control: +15 pmol/min/m²/(mmol/L) (95% CI: 6 to 23; P = 0.002) - HIIT10 vs. control: +16 pmol/min/m²/(mmol/L) (95% CI: 7 to 25; P = 0.002) - Difference between HIIT protocols: 1 pmol/min/m²/(mmol/L) (95% CI: -8 to 10; P = 0.79) No significant differences were observed across conditions for any of the calculated insulin sensitivity metrics.
Why it matters
These findings indicate that acute glycemic improvements following HIIT in older postmenopausal women with type 2 diabetes can be driven directly by enhanced pancreatic beta-cell glucose sensitivity rather than immediate changes in peripheral insulin sensitivity.
Limits
The study is limited by a small sample size (n = 13) and a secondary analysis design. The resting control session was fixed as the first condition rather than fully randomized, introducing potential order effects. Measurements were restricted to a single acute 2-hour post-exercise window, and findings from this older postmenopausal female cohort may not generalize to other populations.
Cited by
- supports A randomized crossover trial demonstrated that a single session of short-interval high-intensity interval training produced meaningful improvements in pancreatic beta-cell glucose sensitivity.