Running at Altitude: What Colorado Runners Need to Know About Fueling and Recovery at Elevation
If you drove up to Breckenridge or Leadville for a trail race last summer and noticed that your legs felt heavier and your lungs worked harder than the effort should have required, you were not imagining it. Running at altitude above 5,000 feet creates physiological demands that flat-land training does not prepare you for, and the consequences show up most clearly in the first 24 to 48 hours at elevation when the body is still adjusting to the reduced oxygen availability.