CORE Measures What Matters
Heat Strain Index
Heat strain describes the physiological processes that cool the body. The harder the body works to cool itself, the greater the strain, and the greater the impact on performance. CORE’s Heat Strain Index (HSI) quantifies this strain in real time using an algorithmic combination of core and skin temperatures.
LEARN MOREHeat Zones
Your Heat Strain Index can fall into 1 of 4 Heat Zones. The heat training zone (Zone 3) is the one that causes physiological adaptations that improve performance. Time spent in each zone is tracked on the CORE app.
LEARN MOREHeat Training Load
Your Heat Training Load is the daily value (on a scale of 0-10) of the amount of time spent in the heat training zone (Zone 3). Optimal heat training involves 2–3 sessions per week, with 45–60 minutes per session in the heat training zone. Sequential days with high Heat Training Load will increase your Heat Adaptation Score.
LEARN MOREHeat Adaptation Score
Under the right conditions, the human body has an amazing ability to adapt. The Heat Adaptation Score uses an evidence-backed formula to calculate how adapted you are to heat on a scale of 0-100%. Use Heat Zones to guide your training towards high daily Heat Training Loads, which ultimately boost your Heat Adaptation Score over time.
LEARN MORECore and Skin Temperatures
Core body temperature is the temperature near internal organs in the torso. Core temp rises when we exercise, and if it rises too high, performance suffers. Skin temperature varies widely depending on environmental conditions. While skin temp helps your body regulate core temp, there is often little correlation between the two. Both are used to calculate your Heat Strain Index.
Heat Strain Index
Heat strain describes the physiological processes that cool the body. The harder the body works to cool itself, the greater the strain, and the greater the impact on performance. CORE’s Heat Strain Index (HSI) quantifies this strain in real time using an algorithmic combination of core and skin temperatures.
LEARN MORE
Heat Zones
Your Heat Strain Index can fall into 1 of 4 Heat Zones. The heat training zone (Zone 3) is the one that causes physiological adaptations that improve performance. Time spent in each zone is tracked on the CORE app.
LEARN MORE
Heat Training Load
Your Heat Training Load is the daily value (on a scale of 0-10) of the amount of time spent in the heat training zone (Zone 3). Optimal heat training involves 2–3 sessions per week, with 45–60 minutes per session in the heat training zone. Sequential days with high Heat Training Load will increase your Heat Adaptation Score.
LEARN MORE
Heat Adaptation Score
Under the right conditions, the human body has an amazing ability to adapt. The Heat Adaptation Score uses an evidence-backed formula to calculate how adapted you are to heat on a scale of 0-100%. Use Heat Zones to guide your training towards high daily Heat Training Loads, which ultimately boost your Heat Adaptation Score over time.
LEARN MORE
Core and Skin Temperatures
Core body temperature is the temperature near internal organs in the torso. Core temp rises when we exercise, and if it rises too high, performance suffers. Skin temperature varies widely depending on environmental conditions. While skin temp helps your body regulate core temp, there is often little correlation between the two. Both are used to calculate your Heat Strain Index.
How To Use the Data
Train Hot
CORE allows you to safely facilitate heat training, which has been proven to increase hemoglobin mass, VO2max, lactate threshold, power output, and blood plasma during controlled laboratory studies.
Race Cool
Heat adaptations allow you to stay cooler for longer, increasing your performance on race day regardless of the temperatures. CORE also allows you to monitor your thermal vitals in real-time so you can pace and cool accordingly.
Getting Started
Available on iOS and Android, the CORE App lets you track and review your heat data, manage the sensor’s settings, and complete firmware updates.
Pair the CORE sensor with your HR monitor, sports watch, bike computer, and training platforms for seamless integration.
Review your heat data in the CORE app, track your heat acclimatization progress, and develop heat awareness to stay cool and perform your best on race day.
Integrate your heat data into training software like TrainingPeaks and Golden Cheetah so you and your coach get get a more informed picture of your performance.
Accuracy and Validation
Accuracy and Validation
We take a rigorously scientific approach to accuracy and validation. Learn about our extensive internal and external testing.
Are you a researcher? Check out our research offering, CALERA® Research.
