How Pacewright works

Your plan is not a template with your name on the top. It is derived from where your fitness is, and when your training changes, the plan changes with it. You are never behind a schedule, because the schedule came from you in the first place.

The plan comes from runs you have done. Your easy pace, your workout paces, and your race estimates are read off your recent efforts, not a generic chart. As you get fitter, those paces move with you.

Your longest run grows out of the running you have already banked, not a date on the calendar. Pacewright adds distance when your recent weeks support it and holds when they don't. A big jump you aren't ready for is where runners get hurt, so it doesn't hand you one to keep a plan on track.

You tell Pacewright two things: which days you can run, and how many runs you want at most. These are separate. From there, the number of runs falls out of spreading your training across the week in a way your body can absorb. You can hand that decision to Pacewright, or tell it to run an exact number of days and it works within that.

Pacewright doesn't lock a fixed block and march you through it. Each session is chosen for where you are right now, weighing the options against your recent load, your goal, and how your last runs felt. A rough week, a missed week, or a great week all feed back the same way. It takes what you did and re-derives from there.

DIAL (Dose In Adaptive Limits) is one readout that answers a plain question: are you doing enough to keep improving while staying inside safe limits? It sits between the least that still moves you forward and the most your body can safely take. DIAL describes where your training is. It doesn't cap you and it isn't a gate. When you want to push or ease off, you can lean it up or down inside safe ranges.

Three guardrails hold the plan in, and they never come off at any setting or tier. A single-run spike cap keeps one run from getting too far ahead of your recent longest. Weekly volume caps keep the whole week in range. And your own feedback, whether a run left you sore or feeling harder than it should have, pulls the plan back.

Doing more than the plan asks, running harder or faster than it calls for, won't make you fitter. Push past what your body can recover from and you set yourself back, not ahead. The plan already asks for the amount that moves you forward.

The spike cap comes from the injury research on runners. In a large runner study, a run more than about ten percent beyond your longest run of the previous month was associated with higher injury risk (Frandsen, 2025). The risk isn't a clean gradient, so Pacewright treats a big single-session jump as the thing to avoid rather than a number to ride up to.

A lot of training tools lean on ACWR, the acute-to-chronic workload ratio. It hasn't held up as a valid injury predictor in runners, so Pacewright doesn't use it. Safety here rests on the spike cap, the volume caps, and your feedback, signals that track how runners get hurt. The FAQ explains why, with the studies.

The best endurance athletes tend to run the large majority of their miles easy and a small share hard, an observation often described near an 80/20 split (Seiler). Pacewright's mix leans the same way. Easy running is where most of the base gets built, and it's easy to run it too hard by accident.

Walk-run intervals for a first 5K and a build toward your first ultra run on the same engine. The coaching and the safety model don't change with your speed. Every session also carries a short note on why it's there, for the times you want to know.