FAQ

Hemoglobin is the protein in the blood that binds and carries oxygen to muscles and tissues. The hemoglobin concentration in an athlete is influenced by a wide range of factors including the type and intensity of a workout; post-training recovery time and hydration; diet; elevation; seasons; and fitness levels.

Hemoglobin mass (tHgb) is the total amount of hemoglobin molecules a person has in the body and is expressed in grams. Hemoglobin concentration is the amount of hemoglobin molecules in a specified amount of plasma volume and is expressed as grams (amount of hemoglobin) per deciliter (amount of plasma volume). Like standard lab draws, Ember measures hemoglobin concentration and the results are expressed as g/dl.

Hematocrit is the percentage of blood that is composed of red blood cells.

During training and competition, endurance athletes need an adequate amount hemoglobin to keep their muscles fueled by oxygen. When hemoglobin levels drop below normal, muscles struggle to get enough oxygen. This causes the heart rate and breathing to accelerate, which negatively impacts athletic performance. Conversely, when hemoglobin levels are too high, oxygen cannot be transported efficiently to the muscles and tissue. This can also negatively impact athletic performance.

Tracking and measuring the changes in hemoglobin levels provide invaluable insight into how an athlete’s body responds to different activities and conditions. Trainers and athletes can use this insight to make smarter training decisions and better prepare for competition. They can also use this data to identify and maintain optimal levels of hemoglobin to maximize athletic performance in competitions.

Ember is the world’s first noninvasive hemoglobin tracker. Using an advanced, LED light sensor that fits over the finger, a highly portable device, and an iPhone, Ember allows trainers and their athletes to track and measure fluctuating hemoglobin levels before and after training. Ember collects, compiles and compares this historical data in easy-to-view graphs that provide valuable insight into which training activities and conditions are most effective.

Within a few hours of arrival at elevation, athletes training at altitude may experience a rise in their hemoglobin concentration due to a decrease in plasma volume (the “water” component of blood). This can be misleading because no new hemoglobin molecules have been made in such a short time. Lower air pressure at higher altitudes means there’s less oxygen available. In response, the body tries to direct more oxygen to the muscles and tissue by increasing the heart and respiration rates.

As an athlete acclimatizes to higher elevation, oxygen supplies to the muscles increase, heart and respiration rates stabilizes or even decreases, plasma volume increases to normal levels which in turn causes the hemoglobin levels to go back down. Continued and sustained elevation training past this point will induce the increase in hemoglobin.

Ember shows you how quickly hemoglobin levels increase at higher altitude, when they peak, and how long those levels stay elevated. Trainers and athletes can use this information to determine how long to train at elevation, how high to go, and how soon to compete after elevation training to maximize gains.

Ember measures the time variation of the heartbeat by examining the PPG (plethysmograph) waveform obtained at the fingertip, whereas an ECG-based chest strap computes HRV based on the variation of the heartbeat in response to electrical impulses from the heart.  Because Ember measures the pulse rate at the fingertip vs. the heart rate, we use the term PRV instead of HRV. 

No.  PRV as measured by Ember has been shown to be statistically equivalent to HRV measured using an ECG monitor

Ember’s non-invasive technology is based on a scientific technique called absorption spectroscopy. Light in various wavelengths is shined through the arterial blood and the amount of blood is measured. Since the hemoglobin molecules in both the oxygenated and deoxygenated state have a unique absorption curve, Ember is able to calculate the hemoglobin levels by examining the amount of light that is absorbed at each specific wavelength. The mobile app then pulls the information from the Ember device and displays it on your smartphone.

Since hemoglobin is the primary carrier of oxygen in the body, hemoglobin values give you an idea of your oxygen-carrying capacity. Oxygen saturation (SpO2) is different. It gives you an idea of how well-saturated your hemoglobin molecules are with oxygen.

The accuracy of Ember in measuring hemoglobin has been shown in controlled studies to be 1 g/dl at one standard deviation. This means that 68% of the hemoglobin values measured on the Ember device should fall within +/- 1 g/dl of the invasive methods used to measure hemoglobin. The accuracy of Ember in measuring pulse rate in the range of 25 – 240 beats per minute is +/- 3 beats per minute at one standard deviation, under no motion condition. Based on an internal study, the trend accuracy, defined as its ability to detect changes in hemoglobin values when compared against an invasive method, was shown to be +/- 0.7 g/dl.

Many physiological factors can impact Ember’s results. These factors include your posture (supine vs. sitting vs. standing), your hydration status (the more hydrated you are, the lower the measured hemoglobin and the more dehydrated you are, the higher the measured hemoglobin), the intensity and duration of a particular exercise, the amount of rest after your exercise (measurement taken soon after an exercise vs. ten minutes after an exercise will be different).

Since physiological factors can impact measurement results, flagging each measurement to a specific activity allows you to compare measurements that were taken under the same physiological condition.

When setting up your Ember account profile, it’s important to enter your age and gender accurately. This allows Ember to identify the appropriate normal ranges for hemoglobin levels. It's also important to enter your location whenever you take a measurement, so that Ember can track your elevation and include that data with your results for a more accurate picture.

1. Wake up the Ember device by pressing on the side button for 3 seconds until you see a series of blinking rectangles. The app will recognize Ember, and your iPhone can now pair with the Ember device.
2. Place the sensor all the way over your finger (preferably your pinky finger on the non-dominant hand if you are using the new mini-sensor or the ring finger of your non-dominant hand if you are using the original sensor), so that the cable runs on top of your hand in a straight line.
3. Tap the start button on your Ember device. Remain quiet and still while the sensor is on your finger. The measurement can take between 30 and 60 seconds to complete.
4. Select the appropriate activity for your measurement.
5. The measurement results will display on the screen. Tap “capture” to save the results in your history.
To learn how to view and interpret your measurement data, view this video.

Avoid taking measurements in direct sunlight, or close to any bright light or computer display. We recommend using Ember in the shade.

Ember requires a smart device with the Ember app installed on it. The Ember by Cercacor App works a smart device running iOS 9.0 or Android 5.0 or newer Make sure you have downloaded the Ember App from the Apple App store or the Google Play store.
Watch the How to Use Ember Video
Download the User Guide.

The Ember by Cercacor app can be downloaded for free from the Apple App store or Google Play store. You will need to type the full name “Ember by Cercacor” to find it.

To share individual results, tap the share button located on the bottom of the results screen. To share your entire results history, open the history tab and select the measurement table. Tap the share button located on the bottom of the screen and a csv file will be sent to the person you choose.

You can discard a data point from your history by opening up the measurement table located in the history tab. Select the individual measurement result you want to delete, then tap the trash icon located on the bottom of the results screen to delete the measurement.

No, you will not lose the previous balance of test credits you had in your account. Reinstall the Ember app to your phone. Go to the Options screen on the app and select Backup/Restore. Follow the directions on the screen and the test credits will be automatically restored on your sensor. In order for the test credits to transfer, you must use the identical sensor you were using before you deleted the app.

Follow the steps outlined in the response for question #9. Please make sure to use the identical sensor you were using with the previous phone.

We respect your privacy and take the protection of your data very seriously.
View our privacy policy.

The optimal time to take a measurement with Ember is first-of-day before getting out of bed. The first-of-day measurement is when your body physiology is the most stable, offering a convenient way to ensure your measurement condition is consistent each and every day. The end-of-day measurement, before going to bed, is another ideal time to take a measurement. You can also take a measurement before and after a workout or even before and after hydration to see the impact these activities have on your hemoglobin values. Frequent measurements over time, taken in a consistent manner, will allow you to get a more complete picture on how your body is responding to various activities, conditions and factors including intensity of workout, recovery, hydration, elevation training, diet, seasons, and more.

Ember measures pulse rate (heart beats per minute), perfusion index (change in blood circulation), oxygen saturation (how saturated hemoglobin is with oxygen), oxygen content (total amount of oxygen in the blood), respiration rate (number of breaths per minute), pleth variability index (variation in the perfusion index over your breathing cycle), methemoglobin (oxidized form of hemoglobin that cannot carry oxygen), carboxyhemoglobin (carbon monoxide that is bound to hemoglobin).

Ember comes with a series of built-in interactive graphs that help you interpret and use your data to improve training. Graphs include: Smart Gauge Display that lets you immediately see how your immediate measurement compares to your last 30-day average, Daily Range Graph that lets you track the impact of each workout by graphing your pre and post workout measurements, Multi-parameter Trend Graph that allows you to track and compare the historical trends of 2 parameters on one chart, and an Elevation Graph that allows you to track the impact altitude has on your body by plotting hemoglobin and other parameters values to the corresponding altitude.

Yes, Ember is a portable, lightweight tool that allows you to measure and monitor hemoglobin levels anytime, from virtually any location. For the most accurate results, we recommend using Ember in the shade and shielding the device/sensor from direct light as well as water.

Ember is not a wearable device. In its current form, Ember is not designed for use during an activity, and is meant to be used first thing in the morning while still in bed, while at rest, in between sets, as well as pre- and post-workout.

Ember accurately measures hemoglobin levels, as well as pulse rate, respiration rate, and blood circulation in less than 60 seconds, and often within 30 seconds.

Posture is known to affect the concentration of substances (hemoglobin) in blood due to shifts in plasma volume. In a controlled study, hemoglobin concentration was lowest in the supine position (lying down), higher in the sitting position, up by 3.2%, and highest in the standing position, up by 10.2% from supine and 6.7% from sitting. These differences in readings can either mask or exaggerate the effects of other factors, like training and altitude exposure, on hemoglobin concentration. By maintaining the same posture each time you test, you can avoid variances in your hemoglobin values.
If you’re interested in the details of the posture study.

Yes – you will be able to connect to the Ember device from your smart device and take a measurement even if you do not have internet access. You will, however, need internet access (Wi-Fi or Cellular) in order to share your data.

The default ranges that the app defined are based on your biological sex and age and can be adjusted. Go to the Options tab on the Ember app and turn on Custom Ranges. Scroll down to PR (pulse rate) and customize your upper and lower limit based on your personal knowledge and goals.

The default ranges that the app defined is based on your biological sex and age and can be adjusted. Go to the Options tab on the Ember app and turn on Custom Ranges. Scroll down to Hgb (hemoglobin) and customize your upper and lower limit based on your personal knowledge and goals.

Giving the app permission to access your location enables the app to automatically capture various environmental details of your location – for example, the weather and elevation. Since your physiology is affected by environmental factors, capturing this information will help you see your body’s response to your environment.

Although any finger could be used for a measurement, for best results, we recommend using the pinky finger of the non-dominant hand if you are using the new mini-sensor or the ring finger of the non-dominant hand if you are using the original sensor. If, for any reason, you are unable to use this finger, we suggest that you choose between the ring or pinky finger from either hand and use that finger consistently for all your measurements.

Ember’s battery lasts for about 120 measurements on a full charge.

Under normal use, regular cleaning of the sensor is not necessary. However, periodic cleaning of the sensor is advised, paying attention to the emitter and detector apertures.
Please see the user guide included with your Ember device for more information.

Ember is not a medical device. It is meant for endurance athletes and trainers who want to monitor athletic performance. If you would like to monitor a physiological condition or disease state, please contact your physician for guidance.

Contact Cercacor Tech Support with any issues using the device.
Email: support@cercacor.com
Phone: 1 (800) 610-8522 (choose option 2 for Tech Support)

Please contact Cercacor Tech support to change or cancel your order.
Email: support@cercacor.com
Phone: 1 (800) 610-8522 (choose option 2 for Tech Support)

You may return your purchase for a full refund for any reason within 30 days of purchase. We will provide return shipping at no charge to you within the United States. You must pay for return shipping if you are returning your purchase from outside the United States.
View our return policy.

Cercacor Laboratories, Inc. (“Cercacor”) warrants to the original purchaser that our products will be free from defects in materials and workmanship under normal use for a period of two years from the date of purchase. Within this period, we will, at our sole discretion, repair or replace any components that fail in normal use at no charge to the purchaser.
View more information on our warranty policy.

After you place an order with us, you are sent an Order Confirmation email with a link to the status of your order. If you are unable to locate this email, you may contact Cercacor at support@cercacor.com with the details of your order. Someone from the Tech Services team will assist you.

Your order number is included in your Order Confirmation email with an automatic link to your order status. When you order by phone, an associate will give you your order number. It’s a good idea to save your Order Confirmation email or write down the order number for future reference. If you forget or misplace your order number, you can get it by contacting Customer Service via email at support@cercacor.com.

Yes. Call (800) 610-8522 (choose option 1 for Sales Support) to place an order for Ember.

We do not include duty or tax in the amount charged to customers outside the US. Customers outside the US are responsible for any duties or taxes assessed against their shipment upon import into their country.

Yes – you can connect the Ember device to any smart device running either iOS or Android.