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Updated: Aug 27, 2025

Conducting Maximal and Submaximal Endurance Exercise Testing to Measure Physiological and Biological Responses to Acute Exercise in Humans
Published on: October 17, 2018
Performance and Submaximal Adaptations to Additional Speed-Endurance Training Vs. Continuous Moderate-Intensity
Vincenzo Rago1, Peter Krustrup2, Magni Mohr2,3
1Faculty of Health Sciences and Sports, Universidade Europeia, Lisbon, Portugal.
Abstract:
We examined performance and submaximal adaptations to additional treadmill-based speed-endurance training (SET) vs. continuous moderate-intensity aerobic training (MIT) twice / week. Twenty-two male endurance athletes were tested before and after 10-week SET (6-12 × 30-s sprints separated by 3-min rest intervals) and MIT (2040 min continuous running at ~70% maximal oxygen uptake [V̇O2max]). The SET group attained greater acute heart rate (HR) and blood lactate responses than the MIT group (d = 0.86-0.91). The SET group improved performance in a time-to-exhaustion trial, V̇O2max, and lactate threshold (d = 0.50-0.73), whereas no training-induced changes were observed in the MIT group. Additionally, the SET group reduced oxygen uptake, mean HR and improved running economy (d = 0.53-0.86) during running at 10 and 12 km·h-1. Additional SET imposes greater physiological demands than MIT resulting in superior performance adaptations and reduced energy cost in endurance athletes.
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