Use of a heart rate-to-ground contact time index to monitor and predict middle-distance running

Abstract

The purpose of the present study was to determine if field-based variables associated with cardiovascular and neuromuscular stress could be used to accurately monitor and predict middle-distance running. Eleven middle-distance runners (age 21.3±1.6 years) completed three trials of steady-state running at 11, 13, and 15 km · h^–1, and test performance was compared with competitive performance (personal best times converted to standardized Mericer scores). Oxygen uptake, heart rate (HR), and stride characteristics (ground contact time [Ct], flight time, step length, and step frequency) were monitored during treadmill running with the ratio of HR:1/Ct calculated. Heart rate and stride characteristics were significantly altered (all Pr=–0.80 to 0.88, Pr=–0.81 to 0.87, Pr=–0.60, P<0.05). Simple measures associated with cardiovascular and neuromuscular stress can be reliably monitored in middle-distance runners. A HR:1/Ct index provides a stable measure at any given submaximal running speed and may provide a useful tool for monitoring and predicting middle-distance running.