80/20 Running: Run Stronger and Race Faster by Training Slower

by Matt Fitzgerald

Each zone has its proper place in a runner’s training. Zone 1 is appropriate for warm-ups, cool-downs, recovery periods between high-intensity intervals, and recovery runs. Zone 2 is targeted in what I call foundation runs (which most other coaches call easy runs) and long runs. Zone 3 is targeted in tempo runs, cruise intervals, and fast finish runs. A typical threshold run comprises a steady effort of fifteen to forty minutes in Zone 3 sandwiched between a warm-up and a cool-down. Cruise intervals are like tempo runs except the middle of the sandwich is separated into multiple shorter Zone 3 efforts. A fast finish run is a foundation run with a short (five to fifteen minutes) effort in Zone 3 tacked onto the end. Zone 4 is typically targeted in high-intensity interval workouts featuring longer intervals (two to eight minutes) and in fartlek (or what I call “speed-play”) runs, which are simply interval workouts with a less formal structure that are done on roads or trails instead of at the track. Zone 5 is appropriate for high-intensity runs featuring shorter intervals (thirty to ninety seconds), hill repetition runs, and more intense speed-play runs.