How Pheidi tracks your intensity mix and flags too much gray-zone training.
Pheidi groups every completed run into one of three intensity zones:
The zone is set when you log a workout. If you record an effort rating, Pheidi maps that effort to a zone. Otherwise the workout type (easy run, tempo, intervals, etc.) determines the zone.
The intensity dashboard shows the share of run workouts completed in each zone over the last 28 days. Only completed run workouts count — cross-training and skipped sessions are excluded. The ring and legend update as soon as a workout is logged.
When more than 20% of your last four weeks falls in the Threshold zone, Pheidi shows a nudge encouraging you to slow your easy days down. The threshold percentage in the legend is also highlighted.
Why 20%? Elite endurance athletes spend roughly 5–10% of training at moderate intensity; recreational runners often spend 40–50%. Above 20%, you're trending toward threshold-heavy training, which research links to slower race times. The nudge points you back toward a polarized 80/20 split.
Easy is shown in green, Threshold in gray (the gray zone, by name), and Hard in red. The color choice mirrors the language used in the warning, so the segment you want to shrink is visually muted.
Science behind this feature from pheidi.training.