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Bodybuilding

The Best Metabolism Tracker for Your Fitness Goals

Avatar photoby Dylan Wolf Updated by Dylan Wolf on Sep 26, 2024

Lumen Review
This post may contain affiliate links (disclosure policy).

Why Lumen is the Best Metabolism Tracker out there

When it comes to your metabolism, too many times do people just guess. Trial and error is something that can certainly teach you how your body works and reacts to different foods, but wouldn’t it be much easier if you could track your metabolism? Well, Lumen has come in with some high end technology that now allows you to do so, and the Generation Iron team has been lucky enough to try it out.

In this post we test and break down the Lumen Metabolism tracker, and see why it is the best metabolism tracker to hit your fitness goals. 

Who is Lumen?

Lumen

Lumen

Lumen

Track your metabolism like never before with Lumen's innovative technology.

Shop Lumen

Lumen is a device-to-app metabolic health coach that measures your metabolism through your breath to help you make the right choices for your body. 

It gives you real-time insights into how nutrition, sleep, exercise, and stress affect your metabolic health and provides tailored lifestyle recommendations so you can make high-impact changes.

Lumen was founded by twin sisters Merav and Michal, who have PhDs in physiology and are Ironman winners. The device is not a substitute for medical advice or treatment, and users should consult with a healthcare provider before making significant changes to their diet or lifestyle based on the data it provides.

What Lumen Offers

Lumen is a cutting-edge flow meter that measures your metabolic efficiency by analyzing the carbon dioxide (CO2) levels in your breath. Although it’s a relatively new entrant in the health and wellness market, Lumen’s portable device, coupled with its user-friendly app, offers a unique approach to tracking metabolism and managing overall health.

Lumen is designed to measure the body’s real-time fuel usage—whether you’re burning carbohydrates or fats—by assessing the CO2 concentration in your breath. This data helps users make informed decisions about their diet, exercise, and overall health.

Lumen Key Features

Feature Description
Real-Time Metabolic Tracking Lumen’s device instantly evaluates your metabolic state, allowing you to see if your body is burning fats or carbohydrates.
Personalized Nutrition Plans Based on your daily metabolic readings, Lumen’s app updates your nutritional recommendations each morning, tailoring meal plans to your unique metabolic needs.
Comprehensive App Integration The companion app not only tracks your metabolic data but also logs meals, analyzes macronutrients, and syncs with other health tracking apps like Apple Health, Garmin, and Google Fit.
Ergonomic Design The handheld device is lightweight, easy to use, and connects seamlessly to your smartphone via Bluetooth.

How Lumen Works

lumen metbaolism

Lumen operates by measuring the concentration of CO2 in your breath, a key indicator of whether your body is primarily using fats or carbohydrates for energy. Knowing how to properly fuel before a workout prevents muscle breakdown and helps with energy/athletic performance. 

The Lumen process is simple: after taking a breath test with the device, your Lumen Level is displayed on the app, showing whether you’re burning fat, carbs, or a mix of both.

The goal is to achieve metabolic flexibility, the ability to efficiently switch between burning fats and carbs. This flexibility is crucial for sustainable weight loss and overall metabolic health. Lumen also provides a Flex Score after 15 days of consistent use, which reflects how well your metabolism adapts to different fuel sources.

In addition to metabolic tracking, the Lumen app offers a detailed breakdown of your macronutrient intake, helping you make better nutrition choices.

By logging your meals and following the app’s suggestions, you can fine-tune your diet to support your metabolic goals.

Cost and Commitment

The Lumen device is priced at $199, with an additional subscription fee of $19 per month to access the full features of the app. This includes daily meal tracking, personalized nutrition plans, and detailed macronutrient analyses.

While the upfront cost and monthly subscription might seem steep, they are justified by the comprehensive metabolic insights and personalized recommendations Lumen provides. For those committed to improving their metabolic health, the investment could be worthwhile.

Pros and Cons

Pros Cons
Instant feedback on your metabolic state Requires daily breath measurements for accuracy
Personalized meal plans updated daily Dependent on smartphone connectivity
Seamless integration with popular health apps Meal logging can be time-consuming
30-day money-back guarantee Ongoing subscription fee
Initial device cost may be prohibitive for some

The Lumen Experience

Setting up Lumen is straightforward, and the device is easy to use. After connecting it to the app via Bluetooth, users can start measuring their Lumen Level each morning. Measuring your metabolism when you wake up helps determine if you’re in fat burn. This is important because sleep helps with recovery post-workout. If you wake up in carb burn, you’ll get tips to move you into fat burn

Over time, the app tracks these levels and provides personalized recommendations to help improve metabolic flexibility. Improving metabolic flexibility helps with body composition (more fat burn and retaining muscle mass).

One potential drawback is that Lumen relies heavily on consistent use and meal logging. For those who find it challenging to maintain this routine or who prefer not to rely on their smartphone for health tracking, Lumen might require more commitment than expected.

Generation Iron’s Opinions

When it comes to a Generation Iron review, it is not complete without our team’s input. I decided to try Lumen to get a deeper understanding of how my body converts food into energy, and the device arrived just five days after I placed the order, and setting it up, along with the app, was a breeze. The app is very easy to navigate, and you can even watch a brief tutorial video that explains how to use both the device and the app.

Setup

Once I connected the device to the app via Bluetooth, I was ready to begin tracking. To be honest, it took about a week to get the hang of the breathing technique, especially keeping the ball in the target zone during readings. If I didn’t do it correctly, the app would prompt me to try again after a short break, and my asthma made this process a bit tricky at first.

Usage

Every morning, I use the app to measure my Lumen Level. My very first Flex score was a four, indicating that I was mainly burning carbohydrates for energy. Over the following two weeks, my morning Lumen Levels ranged between one and five, showing that my body was somewhat able to switch between burning fats and carbs.

After 15 days of tracking, the app gave me my first Flex score of 12.3, indicating moderate flexibility. I wasn’t too surprised by this score, as my Lumen Levels mostly hovered between two and four during that period. The app also provides a chart that tracks my Flex score over time, which makes it easy to see how different lifestyle changes are influencing my metabolic flexibility. 

Each day, the app updates my nutrition plan based on my Lumen Level and other factors. It suggests a specific amount of carbohydrates to consume, offering low, medium, and high-carb options depending on my results. For instance, if I had a high-carb day on Monday and my Tuesday morning Lumen Level shows I’m still burning carbs, the app might recommend a low-carb intake for Tuesday. I don’t fully understand the algorithm behind it, but I’ve noticed a clear connection between my morning Lumen Levels and the carb recommendations the app gives me.

Thoughts

After seeing my recommended carb intake, I check the nutrition section, which breaks down carbs, proteins, and fats and provides a total calorie count for the day. The section also offers meal ideas, complete with macronutrient and calorie information. There are six to twelve recipe suggestions for breakfast, lunch, dinner, and snacks, all updated daily.

While I haven’t been using Lumen long enough to see major changes in my metabolism, I’m already learning more about how my diet and lifestyle choices impact my body. My Lumen Level is gradually decreasing with each test, and I’m becoming more aware of how different foods and activities affect my levels each morning and how I feel throughout the day.

One drawback of the Lumen device is that it only works with smartphones, so if you do not have access to your smartphone every morning it may be a bit difficult. Additionally, the ongoing membership fee might be a downside for some people, but if you’re serious about tracking your metabolism and following the app’s nutrition plan, I believe the extra cost is worth it.

Who Should Buy Lumen

In reality, Lumen is a great tool to learn about your body, which has no specific demographic. Anyone that is interested in improving themselves and their performance could benefit from using Lumen, whether they are bodybuilders, powerlifters, or so on. 

Final Thoughts

lumen

Lumen offers a unique and scientifically-backed approach to understanding and improving your metabolism. While it requires a commitment to daily use and meal logging, the personalized insights and potential health benefits make it a valuable tool for those serious about optimizing their metabolic health. If you’re willing to invest in both the device and the ongoing subscription, Lumen could be a game-changer in your health and fitness journey.

Let us know what you think in the comments below. Also, be sure to follow Generation Iron on Facebook, Twitter, and Instagram.

*Images courtesy of Lumen

Avatar photo

About Dylan Wolf

I work mainly in content writing, focusing my free time on bodybuilding and strength sports. I was introduced to fitness in high school and after watching Generation Iron movies. I love to train. I have competed multiple times, even winning a junior title in classic physique. I have a bachelor's in criminal justice and business obtained through Alvernia University. When I am not focused on work or training, I enjoy watching films or reading about anything and everything.

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