Lumen tailors your fitness plans based on real-time metabolic measurements through your breath. Your breath holds a lot of information, including whether you’re burning carbs or fat for energy. Based on your measurement result, which only takes 20 seconds, Lumen can coach you on how to fuel up before and after workouts and gauge your recovery post-workout. Lumen also trains you to improve your metabolic flexibility, which is how easily your body can shift between burning carbs and fats for fuel. This can help you supercharge your workouts, build and maintain muscle, burn more fat, reshape your body, and recover smarter.

Take a pre-workout breath measurement to determine if you should fuel up before your high-intensity workout. If you’re burning fat, that’s a sign your glycogen stores are low, and you should eat a fast-digesting carb source like a banana to avoid muscle breakdown.
Take a metabolic measurement again 30–45 minutes following your workout, after your heart rate has stabilized. This measurement gauges how intense your exercise was and how well your body is recovering.
During high-intensity workouts like sprinting or weightlifting, your mitochondria rely on carbs for a quick and powerful energy boost. Afterward, your body enters a recovery phase, replenishing glycogen stores and repairing muscle tissue. During this time, it burns mostly carbs.
Once you’ve shifted to fat burn, it means recovery is complete. A longer shift back to fat burn means you had an intense workout.

Choose your workout in the Lumen app, then take a pre-workout breath measurement. Depending on whether the workout is low- or high-intensity and your current fuel usage, Lumen will recommend whether you need to eat some carbs to avoid muscle breakdown.

A Lumen level 4 or 5 is recommended for strength training, as your body needs carbs for anaerobic training and to avoid muscle breakdown. A Lumen level 1 or 2 will help you tap into deeper fat burn for low-intensity cardio training like walking.

Yes, by inputting your desired workout in the Lumen app and measuring your metabolism before exercising, you can find out whether you can safely train fasted. For example, if you’re going to go on a Zone 2 walk and your breath measurement shows you’re mainly burning fats, then you can work out on an empty stomach. However, if you’re going to a HIIT session, you’d need to fuel up with carbs to avoid muscle breakdown.

Lumen automatically adjusts your macros when you input a workout session in the app.

You can connect to 50+ apps directly through the Lumen app.

Yes, you can use Lumen to optimize your pre- and post-workout fueling and recovery for HIIT, CrossFit, or triathlon training by measuring your metabolism before and after your chosen workout session.