The Device does not turn on
Make sure Device is charged. Plug the USB-C cable into the charging port, wait a few minutes and try to turn on the Device again.

The Device does not play a tone when a sample is taken
The Device will play a tone when sufficient saliva is taken. Please continue to try and collect a sample for up to 10 seconds. If Device remains silent, remove the current sensor, discard and try a new one. Follow saliva collection recommendations in section 10 to minimize failure.

The Device is displaying a red light and a blank screen
Press and hold the power button for 5 seconds until the red light turns off. Then turn Device back on again.

The Device doesn’t appear in the device list in the App
Make sure your Device is turned on. Make sure Bluetooth is enabled on your iPhone/iPad.

The Device is displaying a “bad sensor” message and beeping
The currently inserted sensor is either used or faulty. Remove the current sensor, discard and try a new one.


In basic terms, SOSM values increase as dehydration increases, and they decrease as hydration status improves. Most people will exhibit a gradual increase in SOSM as they exercise. This relative change in SOSM is reflected in the status scale bar that appears in the MX3 App immediately after a measurement is taken. While comparison of SOSM measurements with population averages can provide an estimate of hydration status, every individual’s SOSM range and hydration response is unique. To provide the most accurate hydration analysis, SOSM measurements should be compared to a personal baseline measurement taken under optimal hydration conditions.

By comparing with this individual baseline, users can learn more about their personalized hydration range. A small proportion of people will lose an unusually large amount of salt for a given amount of water loss when exercising. For these individuals SOSM may not change significantly, indicating that water has not been selectively lost. Isotonic solutions may assist recovery in these instances.


To produce a saliva sample, generate saliva actively and scoop saliva outwards against your bottom lip using your tongue. To optimize the accuracy of measurements taken with the MX3 System, we recommend the following:

  • Wait at least 10 minutes after any liquid consumption before taking a measurement.
  • Try to maintain a consistent approach to how and where saliva samples are taken.
  • Do not eject sensor until prompted by Device or App.
  • Do not push the sensor too firmly against the lip or tongue.
  • Do not cover the top of the sensor with tongue, lip or any other part of the mouth as it can prevent saliva collection in the sensor.
  • Avoid sampling from overly bubbly saliva samples for more consistent readings.


SOSM Measurements

Salivary osmolarity (SOSM) reflects the concentration of electrolytes and other solutes, including water, in saliva. SOSM has been identified as a non-invasive measure for monitoring of hydration status. Multiple studies have shown that increases in SOSM during exercise are a more accurate measure of active dehydration compared to urine testing.

  • What does a SOSM result mean?

    In basic terms, SOSM values increase as dehydration increases, and they decrease as hydration status improves (so higher number = more dehydrated). Most athletes will exhibit a gradual increase in SOSM as they exercise. The MX3 Hydration Testing System classifies hydration status into four possible categories: hydrated, mildly dehydrated, moderately dehydrated and severely dehydrated, based on the SOSM reading and the user's optimal hydration zone.

  • What is an Optimal Hydration Zone?

    The optimal hydration zone (OHZ) is a personalized SOSM target range that reflects an athlete's fully hydrated state. The OHZ is determined by conducting a series of baseline measurements in a fully hydrated state achieved with a multi-day hydration protocol involving consistent fluid intake. The OHZ is used by the MX3 App to determine an athlete's specific SOSM hydration status thresholds and provide a target range for rehydrating after exercise.

  • Will food or drink mess with an SOSM Measurements?

    Yes, eating or drinking immediately before taking a measurement can impact a SOSM score. We recommend an athlete wait at least 5 minutes after eating or drinking before taking a measurement. If there is substantial food debris within an athlete's mouth, we recommend rinsing with water and then waiting 5 minutes.

  • Is my measurement data saved?

    Measurements taken on the LAB while paired with the MX3 App are automatically saved for later analysis in the MX3 App and portal. If you take an SOSM measurement with the LAB but are not connected via Bluetooth to a mobile device, then the hydration score will not be stored.  

  • Can I export my SOSM measurement data to use in another program?

    Yes. The measurement data (list of hydration scores) can be exported from the MX3 Portal for external analysis or for logging on another athlete management platform.


The MX3 LAB is a powerful handheld device capable of laboratory-grade analysis. Simply insert a test strip, take a small saliva sample and get your actionable results in seconds. 

  • Do I need to calibrate the MX3 LAB?

    No! The MX3 LAB is automatically calibrated by the MX3 Hydration Test Strip and the MX3 App. No calibration strips or solutions are needed.

  • Do I need a phone or tablet with me to use the MX3 LAB?

    No! We recommend you use the MX3 LAB paired with the MX3 App, as it allows you track and analyze past measurements. However, the MX3 LAB may also be used independently, with results displayed directly on the MX3 LAB. However, once the test strip has been removed there is no way of viewing past results, so the result should be recorded prior to discarding the test strip. 

  • How do I charge the MX3 LAB?

    The MX3 Lab can be charged with any standard USB-C charging cable. The MX3 LAB will typically charge fully in less than 3 hours when connected to a computer USB port or USB power adapter.

The MX3 Hydration Test Strip

The MX3 Hydration Test Strip is a single-use electrochemical biosensor that samples saliva to determine the salivary osmolarity (SOSM) and hydration status of the user.

  • Do MX3 Hydration Test Strips have a use-by date?

    MX3 Hydration Test Strips should be used within 24 months of manufacturing. After this date, test strips will still function, but may have reduced accuracy, precision and flow time.

  • Are MX3 Hydration Test strips safe?

    Yes. MX3 test strips are treated with high-dose gamma irradiation following packaging to ensure sterility. Independent laboratory testing has shown that MX3 test strips are non-toxic following cellular toxicity testing.  

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