How Load Distribution Works

Understanding how Pheidi distributes distance across your training week.


The Shape System

Every training week has a shape — a set of multipliers that control how distance is distributed across your run days. The long run is the anchor at 100%, and every other run is a percentage of that distance.

For example, if your long run is 10 miles and a Tuesday easy run has a load of 45%, that run will be 4.5 miles.

Example Week (10-mile long run)
Day Type Load % Distance
Monday Easy 45% 4.5 mi
Wednesday Tempo 50% 5.0 mi
Thursday Easy 40% 4.0 mi
Friday MLR 65% 6.5 mi
Sunday Long Run 100% 10.0 mi

Why Multipliers?

Using multipliers instead of fixed distances guarantees a critical coaching principle: easy runs are always shorter than your medium-long run, which is always shorter than your long run. This hierarchy holds by construction — no post-processing corrections needed.

As your long run distance increases over the course of your plan, every other run scales proportionally. This creates smooth, progressive overload without sudden jumps in any single workout.

Default Multiplier Ranges

Pheidi generates default multipliers based on your training phase, experience level, and race distance. Here's how the ranges break down:

Easy Run Multipliers
Beginner Intermediate Advanced
Base 45–55% 40–50% 38–48%
Build 40–52% 38–48% 35–45%
Peak 38–50% 35–45% 32–42%
Taper 35–45%

Beginners get a flatter shape (higher easy multipliers) for more even volume distribution. Advanced runners are more polarized — the long run dominates.

Other Workout Multipliers
Type Range Notes
Long Run 100% Always the anchor
Medium-Long Run 60–70% Based on race distance and experience
Quality (Tempo, Intervals) 40–50% Build: 50/45/40% · Peak: 50/50/45% (Beg/Int/Adv)

MLR Proximity Adjustment

If your medium-long run falls within 2 days of the long run, its multiplier is automatically reduced by 10% to allow adequate recovery between the two longest runs of the week.

Editing Load Percentages

In the Overview tab of your plan, each workout cell shows a small teal percentage. Click it to adjust that day's load multiplier. When you change it:

  1. The week's shape updates with your new multiplier
  2. All workout distances in that week are recalculated from the updated shape
  3. Changes are saved automatically

This is useful for fine-tuning individual weeks — for example, reducing mid-week load during a busy work week, or bumping up an easy day if you're feeling strong.

Injury and Vacation

Injuries and vacations also work through the shape system — scaling multipliers up or down to adjust your volume. See the dedicated pages for details:

Key Takeaway

The load percentage is the single number that controls how far you run on any given day. distance = long run distance × load %. Everything else — weekly volume, the "hump" shape of mid-week intensity — emerges from these percentages.


Research & evidence

Science behind this feature from pheidi.training.


See also