Assessing Physiological Durability in Trail Runners: Terrain-Specific Responses to a 90-Minute Submaximal Run.

Area of Science:

• Exercise Physiology
• Sports Science
• Trail Running Performance

Background:

• Physiological durability, crucial for prolonged exercise, is understudied in trail running.
• Trail running presents unique uphill and downhill biomechanical and energetic challenges.
• Fatigue development across varied trail terrain remains unclear.

Purpose of the Study:

• To assess physiological deterioration in recreational trail runners.
• To evaluate terrain-specific performance decline after a 90-minute submaximal effort.

Main Methods:

• Twenty-five recreational trail runners underwent pre- and post-90-minute run assessments.
• Tests included a time trial, cost-of-locomotion (CoL) test, and physiological variable analysis.
• The 90-minute run was performed at 66% of the heart rate range between lactate threshold and turn point.

Main Results:

• Time-trial completion time increased by 7.7%, primarily due to slower uphill segments.
• Post-exercise CoL and blood lactate remained unchanged, but heart rate increased.
• Physiological strain was evident with decreased oxygen pulse, tidal volume, and increased breathing frequency during the CoL test.

Conclusions:

• Prolonged trail running causes terrain-specific performance decline and physiological strain.
• Uphill fatigue appears to be a critical limiting factor for recreational trail runners.
• Findings highlight the importance of physiological durability in trail running performance.