Summary: In 34 adults with type 2 diabetes and overweight, 16 weeks of combined strength-plus-aerobic training did not improve a primary glycaemic outcome; instead it lowered fasting GLP-1 (32.8 to 28.4, p=0.04; delta -9.3%, p=0.03) and amylin/IAPP (delta -13.4%, p<0.01) and modestly raised DPP-4 (delta +6.2%, p=0.04). The findings describe how exercise shifts insulinotropic hormone concentrations rather than proving a treatment benefit.
PICO Summary
| Element | Detail |
|---|---|
| Population | 34 adults of both sexes with type 2 diabetes and overweight (mean age 51.7 years, mean BMI 29.5 kg/m2); single-centre randomized controlled trial, Brazil. |
| Intervention | Combined training (strength followed by aerobic exercise), 3 sessions/week for 16 weeks (combined training group, n=17). |
| Comparison | No-exercise control group continuing usual care (n=17). |
| Outcome | In the training group, GLP-1 fell (pre 32.8 +/- 12.1 to post 28.4 +/- 13.5; group-by-time p=0.04). By delta percentage change, GLP-1 decreased -9.3% (p=0.03) and amylin/IAPP decreased -13.4% (p<0.01), while DPP-4 increased +6.2% (p=0.04). GIP and IDE were not significantly changed. No improvement in a primary glycaemic-control endpoint was reported; effect sizes, 95% confidence intervals, ARR and NNT were not provided. |
Expert Commentary
This small mechanistic trial is best read as exploratory rather than practice-changing, and its title should not be mistaken for a glycaemic efficacy claim. The headline result is that combined training lowered, rather than raised, the insulinotropic hormones GLP-1 and amylin while nudging DPP-4 upward. That direction is the opposite of what incretin-based drugs are designed to do, and the authors interpret it as a downstream consequence of improved overall metabolism rather than a therapeutic gain. The most important limitation is statistical fragility: with only 17 participants per arm, an open unblinded design, multiple hormones tested, and several significant signals resting on delta-percentage analyses, the risk of chance findings is high and no correction or confidence intervals were reported. The trial also did not show a clear improvement in a primary glycaemic endpoint, so any clinical inference about blood-sugar benefit would be unsupported. Can I use this with my patients? Not yet. It does not justify changing exercise prescriptions or hormone expectations for anyone with type 2 diabetes, and it certainly does not position exercise as an incretin substitute. I would like to see a larger, adequately powered trial with prespecified glycaemic outcomes and a meal-stimulated hormone protocol before drawing conclusions.
References
Bonfante ILP, Duft RG, Mateus KCS, Trombeta JCS, Chacon-Mikahil MPT, Velloso LA, Cavaglieri CR. Combined training and hormones/enzymes with insulinotropic actions in individuals with overweight and type 2 diabetes mellitus: a randomized controlled trial. Eur J Sport Sci. 2024;24(1):97-106. doi:10.1002/ejsc.12057