Staying active is one of the most important habits for people managing diabetes. Regular exercise improves insulin sensitivity, lowers blood glucose levels, and helps maintain a healthy weight. But for those using continuous glucose monitors (CGMs) like Dexcom, it also raises questions. Will the sensor hold during intense workouts? Can it handle sweat or water? What if glucose levels drop suddenly during a long run or weight training?
According to the CDC, over 37 million Americans have diabetes, and a growing number of them are turning to CGMs like the Dexcom G6 and G7 to track glucose levels in real-time. These devices make it easier to stay safe and in control during daily life—and that includes physical activity.
If you’re using or considering a Dexcom CGM, this guide covers everything you need to know about exercising while wearing a Dexcom. We’ll explain how it works, how to protect your sensor during workouts, how different activities affect blood sugar, and the smart strategies you can use to stay active and safe.
What Is a Dexcom and How Does It Work?
Dexcom CGMs are wearable medical devices that track glucose levels continuously. Unlike traditional fingerstick tests, which offer a snapshot, Dexcom sensors give you a stream of data throughout the day and night. The device consists of three parts:
- Sensor: A tiny wire inserted just under the skin, which measures glucose in interstitial fluid.
- Transmitter: Sits on top of the sensor and sends data wirelessly to your smartphone or receiver.
- App or Receiver: Displays your glucose data, trends, and alerts in real-time.
The Dexcom G7, the latest version, features a compact all-in-one design with a 30-minute warm-up time and a 10-day wear period. It provides readings every 5 minutes, alerting users to rising or falling glucose levels. This is especially useful during exercise, when glucose can shift rapidly.
Because CGMs provide trend arrows and customizable alerts, they’re ideal for tracking how your body reacts to movement, food, stress, and medication. It’s like having a safety net that constantly updates you on your blood sugar, making it easier to take action when needed.
Is It Safe to Exercise While Wearing a Dexcom?
Absolutely. In fact, Dexcom CGMs can make exercise safer by giving you live data during your workout. They help identify patterns and warn you of potential highs or lows before symptoms even begin. However, exercise can introduce a few challenges that are worth preparing for:
Sweat and Adhesion
Sweating during a workout can loosen the adhesive that holds the sensor in place. This is especially true for longer or high-intensity sessions, outdoor workouts in the heat, or activities like hot yoga. When the adhesive weakens, it increases the risk of the sensor coming off or giving inaccurate readings.
To improve adhesion:
- Use skin prep wipes to clean the site before sensor insertion.
- Allow the area to fully dry before applying the sensor.
- Apply a Dexcom overpatch or a specialized adhesive tape for extra hold.
- Avoid lotions, oils, or sunscreen around the sensor area.
Movement and Placement
High-impact activities like CrossFit, running, or team sports can jostle or dislodge a sensor if it’s placed in an area of high movement or friction. Certain sensor placements are better for exercise than others.
Back of the upper arm is usually best—it stays out of the way of waistbands, gear, and bending. Avoid placing sensors near joints, belts, or where your skin folds during motion. For example, stomach placement can be risky during sit-ups or core workouts.
How Exercise Affects Blood Sugar
Understanding how your blood sugar reacts to different types of physical activity can help you prepare and avoid glucose swings. The Dexcom CGM provides valuable insight into these trends.
Cardio and Endurance Workouts
Aerobic activities—such as brisk walking, cycling, swimming, or running—usually lower blood sugar levels. That’s because your muscles use glucose as fuel, and insulin sensitivity increases. For many people, the effect continues even after exercise, which can lead to delayed hypoglycemia hours later.
Watch your Dexcom trends:
- If glucose is dropping fast, consider a small snack before or during the activity.
- Keep glucose tabs or juice nearby, especially for workouts over 30 minutes.
- Set a low alert to warn you early of potential dips.
High-Intensity or Anaerobic Exercise
Short bursts of intense effort—such as sprinting, weightlifting, or HIIT workouts—can cause temporary glucose spikes. These spikes are caused by adrenaline and cortisol, which prompt your liver to release stored glucose. This is a normal response and usually resolves soon after the session ends.
Tracking this in real-time allows for better planning:
- You may not need to treat a post-workout spike unless it stays elevated.
- Log your workouts to compare how different routines affect you.
- Discuss trends with your healthcare provider to adjust insulin timing.
Tips for Using Dexcom While Exercising
If you’re planning to be active while using a Dexcom, these tips can help you get the most accurate data and avoid interruptions:
1. Prepare Your Skin the Right Way
- Clean the application site with alcohol and allow it to dry completely.
- Use a barrier wipe or adhesive enhancer if you have oily or sweaty skin.
- Shave the area if there’s a lot of hair to improve sensor contact.
2. Reinforce with Extra Adhesive
Dexcom sensors come with optional overpatches. For workouts, apply this patch as an extra layer. Other options include third-party tapes like RockTape, GrifGrips, or Tegaderm. These hold the sensor in place even during the sweatiest sessions.
3. Choose the Best Sensor Site
Active people often find the back of the upper arm most reliable. Avoid placing the sensor where it may be compressed, bumped, or moved repeatedly during exercise.
4. Use Trend Alerts and Monitoring
The Dexcom app allows users to set custom alerts for low and high glucose levels. Consider setting:
- A lower alert threshold during exercise (e.g., 80 mg/dL) to catch drops early.
- A rising alert if glucose spikes during intense workouts.
Keep your phone or receiver within Bluetooth range (20 feet) to maintain live data feed.
5. Understand the Lag
Dexcom readings come from interstitial fluid, not blood, which can lag behind actual levels by about 5–15 minutes. During fast changes, especially in workouts, use your symptoms to guide action and confirm with a fingerstick if unsure.
Can You Swim or Shower with a Dexcom?
Yes. The Dexcom G7 is water-resistant for up to 24 hours in up to 8 feet of water. That means swimming, showering, or exercising in the rain won’t damage it. However, prolonged water exposure—especially combined with movement—can weaken the adhesive over time.
Tips to protect your sensor in water:
- Use waterproof overlays for swimming.
- Pat the area dry after water exposure—don’t rub.
- Check adhesive edges and re-tape if needed.
If you’re swimming regularly, consider using waterproof tapes designed for CGMs to prevent peeling or sensor loss.
What to Do If the Sensor Falls Off
If your Dexcom sensor comes off during exercise, it’s not the end of the world. First, check if it can still transmit data. If not:
- Call Dexcom support to report the loss—they may send a replacement if it was early in the 10-day wear period.
- Keep a backup sensor and overpatch in your gym bag or travel kit.
- Document when and how it came off to prevent future issues.
Having a trusted supplier can also make it easier to get quick replacements and supplies.
How Can Aptiva Medical Help You?
At Aptiva Medical, we’re dedicated to helping you manage your diabetes with confidence—especially if you lead an active lifestyle. As a leading provider of Dexcom CGM systems and accessories, we make it easy for patients across the U.S. to get what they need, when they need it.
Why Choose Aptiva Medical?
- Fast, reliable shipping so you never miss a workout
- Adhesive patches, barrier wipes, and overpatches to keep your sensor in place
- Expert help with insurance, Medicare, and authorizations
- Reorder reminders and auto-refill options
- Support from a real team that understands your needs
Whether you’re walking your neighborhood or training for a triathlon, Aptiva Medical has your back.
Call us: (800) 310-2568
Take control of your diabetes with Dexcom—and let Aptiva Medical help you move with freedom and peace of mind.
Frequently Asked Questions
Can I wear compression clothing over my Dexcom sensor during workouts?
Yes, but ensure the clothing isn’t too tight over the sensor area, as excessive pressure can affect sensor readings or cause discomfort.
How soon after applying a new Dexcom sensor can I start exercising?
It’s advisable to wait until the sensor’s warm-up period is complete and initial readings are stable before engaging in physical activity.
Is it safe to use hot tubs or saunas while wearing a Dexcom sensor?
Prolonged exposure to high temperatures may affect the sensor’s adhesive and performance; it’s best to avoid such environments or take precautions to protect the sensor.
Can I use topical creams or sunscreens near the sensor site?
Avoid applying lotions, creams, or sunscreens near the sensor, as they can interfere with adhesion and potentially affect sensor accuracy.
