We are proud to announce the launch of our latest innovation, the Suunto ZoneSense technology – a pioneering advancement in endurance training. ZoneSense uses novel heart rate variability (HRV) features to accurately detect exercise intensity, giving athletes real-time insights into their training. These features were developed and validated by MoniCardi, a spin-off from Tampere University specializing in cardiac monitoring with advanced time-series analysis methods.

In endurance training, the correct intensity of each workout is crucial for achieving optimal results. Historically, athletes have faced challenges to follow workout intensity accurately on a daily basis. Traditional methods often require invasive and cumbersome testing protocols, including, e.g., as blood samples or gas masks, making them impractical for daily use.

Additionally, the training intensity levels are changing on daily basis, differing between different sports, and are impacted by various external factor such as heat and altitude, making it very difficult to follow if an athlete is working out in desired effort level.

A New Era in Training Intensity Measurement

ZoneSense technology addresses these challenges by leveraging advanced HRV analysis to measure the stress levels of the heart during exercise. Using features discovered with Dynamical Detrended Fluctuation Analysis (DDFA), ZoneSense correlates these stress levels with metabolic states, such as aerobic and anaerobic thresholds. This allows athletes to accurately gauge their effort and intensity levels without the need for personal calibration or external testing.

“ZoneSense is a game-changer for athletes looking to optimize their training.” Janne Kallio, Head of Digital Ecosystem at Suunto.

At Suunto, we’ve been focused on helping athletes train more efficiently for years, and one of the biggest challenges has been accurately measuring training intensity. With ZoneSense, powered by MoniCardi’s cutting-edge technology, we are opening new doors in endurance training.

A Breakthrough in Wearable Technology

This marks the first time that this patented technology is being used in a wearable device. The partnership between Suunto and MoniCardi – a start-up company founded by physicists at Tampere University – presents a significant step forward in intelligent heart measurement. “MoniCardi has conducted years of research on advanced time-series analysis methods and heart behavior, in both exercise and daily life, revealing new insights in the medical and sports domains,” explains Esa Räsänen, CEO of MoniCardi. “Having Suunto as the first company to onboard our research is a great step forward in advancing heart measurement in wearables”.

ZoneSense is now available for all Suunto watch owners through after-analysis in the Suunto App, when training with a heart rate belt. Live measurements are available on the latest Suunto models: Suunto Race S, Suunto Race, Suunto 9 Peak Pro and Suunto Vertical. Suunto Ocean will also support ZoneSense, later in autumn 2024.