Train for a time 7-10 seconds per mile faster that your best “Altitude” Time.
Do High-Intensity interval training should be no longer than 600-meter repeats.
All intervals should be 2-10 seconds faster per mile than target race pace
Do short race efforts
Time Trials of less than 1600m
Short “tune-up” races: 1600m or 3200m, avoid racing 5ks within 4 weeks before NXR.
Racing at 5K distance at altitude will have a “de-training” effect for a sea-level 5k because you will not be able to race near sea-level race pace at altitude.
Ideally, you will want to arrive at the race location three-days early. In the case of NXR, the increased oxygen concentration will be immediately available. (The altitude effect window is between 1 day to 2-3 weeks.)
Target Goal can be 7-seconds per mile faster than your best race at altitude. Pace your first mile accordingly. At sea-level, the first 1.5 miles should feel easier than altitude, by comparison. You should experience the same discomfort in the last half of the race but be able to maintain the your faster pace.
Conditions for a PR:
Good to Peak Fitness
Good weather conditions
5,000ft in Elevation or Higher.