PMID 41777799

Research
All papers

Comparative effects of high-intensity interval training at low and moderate altitudes on 5000-m performance and perceptual responses: A randomized controlled trial

Fentaw S, Tadesse T, Birhanu Z

Question

Does 8 weeks of 4 x 4 min HIIT performed at low altitude versus moderate altitude differently affect 5000 m performance, pacing, and RPE in moderate-altitude resident runners?

Summary

Moderate-altitude resident distance runners improved 5000 m time, pacing speed, and perceived exertion after adding 4 x 4 min running HIIT twice weekly for 8 weeks. Training at low altitude appeared to produce somewhat larger pacing and RPE benefits than the same structure at moderate altitude.

Methodology

  • Moderate-altitude resident trained distance runners
  • 42 participants.
  • Running.
  • Work intervals: 4 min at 100% vVO2max.
  • Recovery: 3 min active recovery at 70% vVO2max.
  • Intensity: 100% vVO2max work; 70% vVO2max recovery.
  • About 40 min including warm-up and cool-down.
  • 2 sessions/week.
  • 8 weeks.
  • Randomized controlled field trial
  • 5000 m time, Pacing speed, and RPE were tracked.

Outcomes

5000 m time

Both HIIT altitude groups improved 5000 m time.

HIIT1220m delta 20.1 +/- 23.7 s, p=0.007; HIIT2850m delta 16.7 +/- 25.9 s, p=0.003.

Improved

Pacing speed

HIIT groups improved key kilometer speeds versus control, especially first and fifth kilometers.

Significant group-by-time interaction in all km segments; group effects at 1st km p=0.034 and 5th km p=0.044.

Improved

RPE

Runners reported lower race RPE after HIIT, with greater changes in the low-altitude group.

RPE sensitivity analysis reported large observed effects; exact values in supplemental table.

Improved

Altitude comparison

Low-altitude HIIT generally produced larger pacing and perceptual changes, but the study was small and field-based.

Mixed

Insights

  • A 4 x 4 min running HIIT protocol can be integrated twice weekly into a runner macrocycle.
  • For moderate-altitude runners, low-altitude quality sessions may allow better pace and RPE outcomes.

Limitations

  • Athlete-only sample
  • Altitude-specific logistics
  • Small final sample
  • No direct heart-rate/lactate/ventilation monitoring
  • Outdoor environmental variability

Safety

  • No adverse events were described in the extracted article text.
  • Six participants were excluded from final analysis for adherence or posttest missingness.