This content is for informational purposes only. Always consult your healthcare provider before making health decisions. CGM data should not replace professional medical advice.
Device rankings for active use are based on published MARD data, manufacturer waterproofing specifications, adhesive performance reports, app integration capabilities, and verified retail pricing as of May 2026.
What CGMs tell active users
For performance-focused individuals, CGMs provide data on how training sessions, fueling strategies, and recovery periods affect glucose patterns. Key data points include how quickly glucose drops during sustained effort, how carbohydrate timing affects energy availability, and how different recovery strategies influence overnight glucose stability.
This information is product data — what the sensor measures and displays — rather than medical guidance. What an athlete does with that data is a personal and professional decision.
| Device | Rx required | Monthly cost | MARD | Waterproof rating |
|---|---|---|---|---|
| Dexcom G7 | Yes | ~$350 | 8.2% | 8ft / 24hr |
| Dexcom Stelo | No | ~$99 | 8.7% | 8ft / 24hr |
| Abbott Lingo | No | ~$49 | 7.8% | 1m / 30min |
| Levels Health | No | ~$199 | 7.8% | 1m / 30min |
See what each device costs over your training or monitoring period.
1Dexcom G7 — Best overall for performance
The Dexcom G7 is the most capable CGM for performance-focused users who have a prescription. Its 8.2% MARD makes it among the most accurate devices available, and it connects to a wide ecosystem of third-party fitness apps. The G7 is waterproof to 8 feet for 24 hours — significantly more robust than competing sensors for swimming and contact sports. Real-time alerts and 10-day sensor life are consistent advantages.
Cost is the main barrier. At ~$350/month before insurance, it's the most expensive option listed here. With insurance coverage, the out-of-pocket cost can drop substantially for those with a qualifying diagnosis.
2Dexcom Stelo — Best OTC for data-focused athletes
The Dexcom Stelo is the strongest OTC option for athletes who want detailed glucose data without a prescription. It shares Dexcom's waterproofing standard (8ft / 24hr) and connects to Dexcom Clarity for trend analysis. The app presents raw glucose data with trend arrows, which experienced users find more actionable than score-based systems.
At $99/month, it's significantly cheaper than the G7 while delivering comparable accuracy for non-clinical use. The 15-day sensor life also reduces sensor swap frequency — useful for athletes who want uninterrupted monitoring through training blocks.
Calculate costs for 30, 90, or 365 days across all devices.
3Abbott Lingo — Best budget option
The Abbott Lingo has the best published accuracy (7.8% MARD) among OTC devices and the lowest cost. Its waterproofing spec (1m / 30min) is less robust than Dexcom's offering, which matters for swimmers. The Lingo Score system is approachable but less granular than raw graph data — a tradeoff that suits casual activity tracking better than detailed performance analysis.
4Levels Health — Best for coaching + data
Levels Health adds a coaching and analytics layer on top of CGM hardware. The platform scores meals by glucose response, tracks activity impact, and provides trend analysis. For athletes who want structured interpretation of their data — not just raw readings — this platform approach is genuinely useful. At $199/month, it sits between Stelo and G7 on cost.
What active users should look for
Waterproofing
Dexcom sensors (G7, Stelo) are rated to 8 feet for 24 hours. Abbott Lingo and Levels-supplied sensors are rated to 1 meter for 30 minutes. For swimmers and high-sweat activities, Dexcom's waterproofing is a meaningful advantage.
Adhesion during activity
All sensors listed use medical-grade adhesive designed to hold through sweat. Supplemental adhesive patches are widely used by athletes for longer-duration sessions. None of the sensors listed require special athletic-specific products to maintain adhesion under typical training conditions.
Real-time alerts
The Dexcom G7 and Stelo both support real-time glucose alerts. The Stelo's alerts are configured for wellness ranges rather than clinical thresholds. Lingo and Levels do not offer the same alert customization as Dexcom's platform.
Which CGM for your sport?
Endurance athletes (running, cycling, triathlon): Dexcom G7 or Stelo for real-time trend data during long sessions. Levels Health for structured fueling feedback post-workout.
Strength training and HIIT: Any of the four devices works well. Lingo's score system is approachable for those new to CGM. Stelo for those who want more granular data.
Swimming: Dexcom G7 or Stelo only, given the superior waterproofing. Lingo and Levels-supplied sensors are not rated for extended water exposure.
Team sports: Stelo or Lingo for OTC convenience; G7 for higher accuracy if prescribed. All sensors are low-profile enough for most sports.
Our recommendation
Dexcom Stelo is the best starting point for most active users without a prescription — strong accuracy, the best waterproofing in the OTC category, and Dexcom's mature data platform at $99/month. If you have a prescription and want clinical-grade accuracy, the Dexcom G7 is the step up. Budget-constrained athletes should consider Abbott Lingo at $49/month as a capable starting point.
Use our free calculator to compare CGM costs for any monitoring period.