Continuous glucose monitoring has given exercise researchers a new metabolic window: real-world, minute-by-minute glycemic response across 12 weeks of structured training.
12-Week CGM Findings
Zone 2 group at week 12:
- Fasting glucose reduced by 6.2 mg/dL (p=0.01)
- Time-in-range (70–140 mg/dL) improved from 79% to 91%
- Post-meal glucose spike amplitude reduced by 31%
HIIT group at week 12:
- Fasting glucose reduced by 4.1 mg/dL (NS at p=0.07)
- Time-in-range improved from 78% to 84%
- Post-exercise glucose spike present in 67% of sessions (stress-response cortisol)
Observational Caveat
This is observational data. Participants self-selected training adherence, and the HIIT group averaged 2.4 sessions/week vs. the protocol's 3. An RCT with matched volumes is needed before conclusions about head-to-head superiority are drawn.
