Continuous Glucose Monitoring: A Runner's Field Test

Continuous glucose monitors (CGMs) — a small sensor worn on the arm for 14 days, sampling interstitial glucose every 1–5 minutes — have moved from medical tool to performance optimization in the last three years.

What We Found

Fifteen Idigov Runners volunteered for a 30-day CGM experiment. The data revealed:

• Highly individual food responses — the same banana spiked one runner to 180 mg/dL and another to 110 mg/dL
• Pre-run carb timing matters more than carb quantity — a fast-absorbed gel 5 minutes before outperformed a larger carb meal 60 minutes before for most runners
• Post-run glucose recovery is a recovery KPI — runners whose glucose stabilized within 60 minutes of finishing showed faster overall recovery markers
• One runner discovered pre-diabetic glucose patterns despite normal HbA1c — got medical follow-up, started addressing it before clinical diabetes

What CGMs Actually Tell You

• Your individual glycemic response to specific foods (not generic glycemic index tables)
• Sleep quality impact on metabolic health — poor sleep clearly raises next-day glucose
• Stress and glucose — cortisol-driven spikes are visible and correlate with subjective stress
• Pre-race carb-loading effectiveness — you can see whether your protocol is actually filling glycogen

What They Don't Tell You

• Muscle glycogen is not measured by CGM — interstitial glucose is a proxy, not the storage tank
• Performance ceiling is not predicted by glucose patterns alone
• Optimal range for athletes is debated — "flat is good" advice from longevity influencers may be overcorrected for endurance athletes who *need* glucose flexibility

Should You Try One?

• Yes — if you have unexplained energy crashes, recovery problems, or family history of metabolic disease
• Maybe — if you're optimizing race fueling and want to A/B test different protocols
• Probably not — if you're already healthy, performing well, and would obsess over the data without acting on it

Available in Dubai

• Levels — premium CGM coaching app, ships sensors
• Hello Inside — European service, ships UAE
• Direct purchase — Abbott Libre 3 sensors at major Dubai pharmacies, no prescription required for self-use

Not a forever tool. A two-week experiment that teaches you something specific about your physiology, then you take that knowledge forward.