Is the CORE sensor waterproof?
The CORE sensor is waterproof and can be submerged up to 1.5m. Triathletes will face no issues wearing the sensor during the swim leg. Accuracy however is not guaranteed under water. The main issue being weak or non-existent ANT/Bluetooth connections.
After active sports and use in water, especially sea water, we recommend rinsing CORE with clean water and soap. The medical-grade plastic case can also be disinfected using 70%-75% alcohol.
Do not use acetone or 100% alcohol as these solvents will destroy the plastic material.
The specially design magnetic power cable means that the CORE device remains closed/sealed.
Is the CORE sensor reusable and rechargeable?
The CORE sensor is designed to be reusable and can be recharged and used continuously.
- When a chest-strap, heart rate monitor strap or arm strap is used, the CORE unit can be left on the strap (and only removed if the straps are washed).
- The medical-grade adhesive patches are single-use and can be removed and replaced with a new adhesive patch.
- If the device is swapped between people, the medical grade plastic is designed to be non-irritating and can be simply cleaned with alcohol for hygiene.
Where do I find the sensor serial number?
The sensor serial number is 12-digits long and can be found on the rear of your sensor
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Is a phone and the CORE App needed?
For everyday use - the CORE sensor saves data internally and broadcasts to paired devices that are within range. This means that a phone and the CORE App is not necessary for this type of use.
The role of the CORE App
For regular use, the CORE App is useful as it synchronize the data from your CORE sensor (independently to paired devices). where it is permanently stored and available. The advantage is that the CORE App can provide advanced insights and analysis.
To set-up the CORE sensor, update the firmware and adjust settings, the CORE app is required. The CORE App allows the CORE sensor to be owned (and for sharing to be managed).
For complete control of the CORE sensor and to benefit from the latest updates and improvements - it is recommended to have the CORE App installed and setup. Read more setting up the CORE App.
How long does it take for the CORE to show data?
There are a few things to consider with respect to data from the CORE sensor
For the most accurate results, the CORE sensor should be worn before starting an activity (at least 10 minutes before).
The moment the CORE sensor starts to get valid data, it will quickly be able to record and broadcast skin temperature and this updated every 2 seconds.
When the CORE sensor is first worn there is an initial 10 minute calibration period. During this time the CORE will calculate values but they are considered lower quality. For this reason we recommend putting on the CORE before starting a workout.
As long as you are wearing CORE correctly, the measurement will update every minute with your real-time core body temperature.
If CORE receives invalid data e.g. it is worn incorrectly or not on the body at all, it will take longer before it will deliver a valid core temperature after you start wearing CORE correctly.
The CORE sensor will show valid data on connected / paired devices and also stores data onboard which is synchronized via the CORE App.
Does the CORE sensor measure when disconnected?
When you are wearing the CORE sensor, it will continue to record.
The CORE sensor has an internal memory which stores data, even when disconnected from the CORE App for Android or iOS. The next time you start your app and connect, the App will synchronise and load the metrics.
If you are using the CORE sensor with a paired devices cycle computer or watch, the CORE must remain within range to record the core body temperature metrics to the FIT file. In the rare case that the signal to the CORE sensor is temporarily lost, the device will not display the real-time values and the FIT file will have missing data.
Can the CORE sensor be used in UCI, ITU and IAAF races?
The short answer is yes, the CORE sensor can be used in UCI, ITU and IAAF races
The CORE Body Temperature Monitoring sensor is similar to Heart Rate Monitor sensors in that it uses ANT+ and BLE and it paired to an athletes sport computer or watch and the data is only visible to them.
The CORE sensor is not a telemetry device. The CORE sensor is fastened securely to the heart rate monitor strap using the securing clips.
Cycling Sport
The current version 10.06.2021 UCI (Union Cycliste Internationa) Cycling Regulations states the following:
§ 4 Onboard technology
1.3.006 bis
Devices which capture or transmit the following physiological data are authorised: heartrate, body temperature, sweat rate. The authorisation is, however, limited to transmission protocols which enable only the rider concerned to view the data during a competition.
Triathlon
The ITU (International Triathlon Union) does not limit the use of core body temperature monitoring sensors during competition.
Athletics and Running Races
The IAAF (International Association of Athletics Federations) World Athletics Technical Rules (1. November 2019) states:
6.4 For the purpose of this Rule, the following shall not be considered assistance, and are therefore allowed:
6.4.4 Heart rate or speed distance monitors or stride sensors or similar devices carried or worn personally by athletes during an event, provided that such device cannot be used to communicate with any other person.

