Scalable elastic band resistance training improves glycemic control in older adults with type 2 diabetes: a CGM-based randomized crossover study

Objectives: To compare the acute and 24-h glycemic effects of scalable aerobic, resistance (elastic bands), and combined training in older adults with Type 2 Diabetes Mellitus (T2DM) using Continuous Glucose Monitoring (CGM).

Design: A randomized crossover trial.

Methods: This randomized crossover trial enrolled 30 older adults with T2DM, of whom 23 completed the aerobic, resistance, and combined exercise sessions and were included in the per-protocol analysis. Interstitial glucose was continuously monitored using CGM over 14 days. A non-exercise control condition was defined as the average of four pre-training days. Post hoc Bonferroni correction was applied to mean glucose, TIR, and GRI, while the remaining CGM metrics were treated as exploratory. Exploratory GEE models compared each condition with control after adjustment for age, sex, BMI, and HbA1c.

Results: In exploratory GEE analysis, only combined training was associated with lower 24-h mean glucose versus control (β = −0.513, p = 0.0019; Bonferroni-corrected p = 0.017). No other principal-outcome GEE comparison remained significant after Bonferroni correction. Aerobic training produced the steepest acute glucose decline (−0.0256 mmol/L/min). In secondary pairwise comparisons, combined training had higher TIR than aerobic training, while resistance training had lower GRI than aerobic training after Bonferroni correction. Combined training produced the latest glucose nadir (185 min).

Conclusions: In exploratory GEE analysis, only combined training significantly reduced 24-h mean glucose relative to control. Secondary pairwise comparisons showed modality-specific differences in TIR and GRI. Elastic-band resistance training may be a practical, low-cost strategy warranting further study.