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Updated: Feb 4, 2026
Author Spotlight: Investigating HR-Dependent Cardiac Function in Mouse Models Through a Novel Atrial-Pacing Approach
Published on: July 21, 2023
Monitoring heart rates to evaluate pacing on a 75-km MUM
Pascal Balducci1, Damien Saboul2,3, Robin Trama2
1Inter-University Laboratory of Human Movement Science, Claude Bernard Lyon 1 University, Villeurbanne, France - pascal.balducci@etu.univ-lyon1.fr.
Background:
To examine pacing among twelve males on a 75-km mountain ultra marathon (MUM) and to determine whether pacing relates to final performance.
Methods:
Speed and heart rates (HR) were measured continuously using a HR monitor and a global position system device. An Index of Pacing (IP) was calculated by dividing the average race speed by the speed on the first race segment. In addition, percentage (%) of heart rate reserve (HRres), coefficient of variation (CV) in speed and in percentage of HRres were analyzed throughout the race.
Results:
Performance time was correlated with IP (r=-0.88, P<0.01), % of HRres (r=- 0.72, P<0.05), and CV in % of HRres (r=0.80, P<0.05), but not with CV in speed (r=-0.12, P=0.9). On the entire race, evolution of HR was not dependent on the elevation gain.
Conclusions:
Tracking HR is a safer way to rate pacing than speed tracking on a hilly course.
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