I wouldn't call myself progressive in using sports technology. Before embarking on a new trend, I tend to wait a couple of years to see if the buzz is still around and has improved since its inception.
I used the same rationale for blood-glucose monitoring. I read many reviews... and waited. Then I got the opportunity to test Supersapiens technology and its new Energy Band, the first watch to display glucose concentrations in real-time.
So, while I may not be progressive in adopting every new gadget on the market, I am inquisitive. And I was even more interested in seeing how my real-world test of Supersapiens compared to others.
The Energy Band watch is extraordinarily compact, weighing a mere 45 grams on my kitchen scale. I used it both as the only device to monitor my bike rides, runs, and swims and in conjunction with a second device. And even when I had both units on me, I hardly felt it on my wrist. It's probably the least noticeable device I have ever used; a rare trait in a market where screens are getting bigger and features – many of which we'll probably never use – multiply by the day.
Instead, the options on Supersapiens' Energy Band are few, but you'll use them all. On the screen, you can choose to visualise three different pages through the up/down buttons: on the first, you see the glucose concentration and its trending arrow; on the second, the time of day; while the third gives an idea of your daily's glucose exposure and if you're above or below their recommendations. The third central button gives you access to settings: sound, light, alarm, units, pairing mode, and shut down.
Simple as that. And honestly, it doesn't need to be any more complicated. The unit is conceived as an external monitor of your glucose levels and doesn't require the use of the Supersapiens app. However, the app is still an essential component, and you'll need it for the first pairing of the sensor.
The watch's body is rectangular and feels quite sturdy, and the strap is anchored firmly on the screen so it doesn't bounce. It can be easily placed on your handlebars as well.
Connections and app functions
To monitor your glucose levels, the Energy Band pairs with the button-like Abbot Libre sensor, which you stick directly to your arm. Often used by diabetics to avoid needles, these slim sensors actually measure the percentage of glucose in the interstitial fluids in between the cells, not in the blood, although the result is much the same. Once you've attached this, you still need the Supersapiens app to pair the sensor, as you can't pair the sensor directly to the Energy Band. After the pairing process, you then need one hour of warm-up before seeing your glucose values displayed.
In use, I have experienced some issues in pairing the sensor with the app. Supersapiens has explained that this can happen with phones with older NFC (Near Field Communication) or NFC antennas placed in different locations. So, it can take a 30-second delay or repeated scans for the sensor to pair.
After pairing, though, the Energy Band doesn't need the Supersapiesn app to function and display glucose levels on its screen in real-time via Bluetooth connection with the sensor. That means you don't need to have your phone with you when you exercise, though chances are pretty high you will (and probably should) have it with you when you're out riding.
All that said, the app is still an essential key to Supersapiens. It is filled with articles and guides to help you get the hang of it, and it allows you to see how your glucose levels have been acting during the day. You can also create events (training sessions, races, or meals) on the app to understand how your glucose has changed during those times. And even after a month of daily use, there's a lot I haven't had time to go through: for example, setting my glucose performance and recovery zones, or my maximum glucose exposure.
The Energy Band recharges reasonably quickly (around 90 minutes), but it also needs to be charged daily with the backlight turned off or every 12 hours with the light turned on. At least, that was my personal experience and one of the main downsides of the unit I could find.
One way to create training events from the Energy Band without using the app is through the central button of the display. You have the "train" option to choose when you press it, which starts a timer. Once you finish your activity and press finish, it will automatically display on the Supersapiens app. This function will help you understand how your blood glucose has behaved during your session, so you can adapt your fuelling if needed.
Through this option, I discovered something I had never heard of before: rebound hypoglycemia. This is a state of low blood glucose levels that – in athletes – happens immediately after the beginning of a workout if carbohydrates were ingested 30-60 mins before exercise. The first time I used Supersapiens, I noticed a drop in blood glucose immediately after training and then a second rise after 40-45 mins. After flagging the activity and seeing the pattern, I spoke with Asker Jeukendrup (one of the Supersapiens' scientific advisors and nutritionist for Jumbo-Visma), and the mystery was solved. It all depended on what and how long before training I ate. If ate eat carbohydrates one or two hours before exercise, I experienced rebound hypoglycaemia. On the other hand, if I eat around three hours before a session, my blood glucose levels are more steady and never really drop at the beginning of the activity, something which is good for performance.
Supersapiens defines a glucose spike as a sharp rise in glucose levels (>2mg/dL/min or 60 mg/dL in 30 mins). At the same time, it says it rises more steadily when glucose is rising >1-2mg/dL/min or 30-60 mg/dL in 30 mins. And on their app, they have a function to set individual recovery and performance blood glucose zones, which will make it more meaningful to interpret the numbers you'll get through the Energy Band or app.
Finally, if you're exercising and sweat a lot – or you swim and run, too, for example – I highly suggest getting an adhesive performance patch to apply the stick-on the Abbot Libre Sensor. When I didn't use one, I lost a sensor (it got stuck into my cycling winter jacket). Also, make sure you replace the patches as soon as they peel off your arm. In two weeks of heavy use, I had to change three different patches to ensure the sensor was well protected throughout all my activities. This is despite the patch supposedly being meant to last 14 days for those performing low-intensity sessions in a controlled environment.
The Energy Band is a very comfortable watch, and the fact that it's the first to measure glucose concentrations in real-time would be worth a five-star review alone. The only downside is the limited battery life of 24 hours — a point Supersapiens should work on for its future models. Apart from that, Supersapiens' glucose monitoring has taught me things I had never heard of before and helped me pay more attention to my fuelling strategy. I am sure that as soon as they display ketones and lactate levels in real-time (as well as glucose concentrations), they'll change endurance sports forever.
The Energy Band is also 50 metres (5 ATM) waterproof, and its retail price is €159.