To determine your ideal race pace on race day, rely on your perceived exertion and the paces maintained during your key training sessions, rather than the algorithmic predictions of your GPS watch.

noli's read

The advice to favor Rate of Perceived Exertion (RPE) is widely supported by sports science research. An observational study by Passler et al. (2019) confirms that sports watch algorithms have significant margins of error in predicting performance, as they rely on indirect estimations of your physical condition. Conversely, work by Pageaux (2014) demonstrates that perceived exertion is a highly precise physiological indicator, capable of integrating muscle fatigue, mental state, and weather conditions in real time. Furthermore, a review by Abbis and Laursen (2008) on pacing strategies shows that adjusting to your sensations allows you to avoid premature exhaustion much more effectively than blindly following external data. Nevertheless, the watch remains useful for calibrating the first few kilometers, thereby avoiding a start that is too fast due to race-day adrenaline.

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