Garmin Heat Strain Index

Real-time Heat Strain Index is now available on Garmin watches and cycling computers! The Heat Strain Index is a value from 0–10 that indicates how hard your body is working to stay cool. Many athletes start losing performance at a value of 3 or 4. So this metric is a great complement to core temperature. It reminds you when to cool off, and possibly even when to slow down.

This update also features an alert when your heart rate monitor is not paired to your CORE sensor. Remember that, during sports, a heart rate signal is necessary for CORE to provide accurate data.

To get this update on your Garmin, go to the Garmin Connect App and update the CORE DataField. Then, under settings, enter ‘2’ in Display Option. The display will alternate between core temp and Heat Strain Index. Please note that this feature does not work on older devices. For example, the Forerunner 920XT does not have enough memory to support it.

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