The hardest part of marathon training isn’t the long run. It’s making the whole block survive a cold, a work week, a bad night’s sleep, a week your body just won’t cooperate. Reshape treats those weeks as signal, not noise. The plan regenerates from what you actually did, so one rough week stays one rough week.
Sixteen weeks in three phases
The first block is base. Mostly easy mileage, one weekly threshold session, and a long run that extends one step at a time. Here the plan asks your body to get efficient at burning fuel aerobically and to tolerate the volume a marathon block is about to ask of it.
The middle block is build. The long run stretches toward race distance. Threshold work lengthens. Some long runs end with a real stretch at marathon pace so your body learns what that effort feels like on tired legs. This is where the marathon gets built; it’s also where most injuries happen in blocks that don’t know to pull back.
The final block is peak and taper. The highest-quality sessions live here, then volume drops sharply in the final two to three weeks so you arrive rested. The taper is built in. Reshape won’t let you cram one last big long run the week before race day even if you want to.
Three marathoners this plan fits
- First marathon. The goal is the finish line, healthy. The plan prioritizes gradual long-run extension, caps week-to-week increases, and keeps quality work modest. Finishing is the job; a time is a bonus.
- Chasing sub-4, sub-3:30, sub-3. Give the app a race date and a target. Intervals and threshold paces are scaled to your current VDOT, the block is periodized, and weekly regeneration catches bad weeks before they compound into a failed peak.
- Training around life. If the sixteen-week block has to flex around a work trip, a conference, a sick kid, Reshape reads what you actually ran and rebuilds from there. The taper still lands on race day, just built out of different weeks.
What a marathon week is built around
A build-phase marathon week typically includes five or six days of running. Inside a typical week:
- One threshold session. Sustained time at the pace you could hold for roughly an hour. Marathon performance is strongly correlated with how much of your race pace sits below threshold.
- One interval session. Short, fast reps at 5K-to-10K effort. These keep the top end sharp so marathon pace feels controlled.
- One long run. The centerpiece. Extended each week within a cap. Some long runs finish with a segment at marathon pace once the aerobic base is there.
- Two or three easy runs. Short, conversational, protecting the quality of the hard days and adding aerobic volume.
The specific session lengths, interval counts, and paces are composed by Reshape from your current VDOT and where you are in the block. A strong week adds load carefully. A rough week pulls back. Long-run increases are capped so you can’t jump into injury territory.
Built on what you actually ran
- Reads Apple Health. Up to eight weeks of running history, including VO2 Max, pace, mileage, recovery signals.
- Workouts on Apple Watch. Every session lands on the watch the night before with pace targets on the face.
- Weekly regeneration. The next week is rebuilt from what you completed, with caps on how much the long run and weekly load can change week to week.
- Plain-language coach notes. Every workout comes with a short note explaining why it’s in the plan and how it connects to your race.
Reshape isn’t the right pick if…
- You want a human coach in the loop. Reshape is software only.
- You want strength programming bundled in. Reshape is running-only. Runna has a library for that.
- You train on Android, Garmin, Coros, or Fitbit. Reshape is iPhone and Apple Watch only.
Common questions
Sixteen weeks is the standard block. Twelve is possible if you already have a half-marathon base and have been running consistently. Twenty or more makes sense for a first marathon so volume has time to build at a rate your body can absorb. Reshape reads your Apple Health history and sets the starting week to match your actual base.
The long run. It's where marathon-specific fatigue resistance gets built. Reshape grows the long run gradually across the block, caps the week-to-week increase so you don't jump into injury territory, and in the build phase occasionally finishes a long run with a stretch at marathon pace. A typical peak long run for a first marathon sits at 28–32 km; for PR-chasers it can go a little longer.
Four to six for most runners. First-time marathoners do well at four days; more experienced runners chasing a PR typically need five or six. Reshape asks how many days you can run and builds the week around that number, rather than forcing a fixed schedule. The emphasis is on getting the long run and one or two quality sessions done, not on hitting an arbitrary day count.
Yes. Every workout is sent to your Apple Watch the night before with pace targets on the face, and the session is recorded on the watch. iPhone is where you see the plan, read the coach notes, and log completion after each run. Reshape is iPhone and Apple Watch, not iPhone alone.
Yes. Give the app your race date and a target. Intervals and threshold sessions are paced from your current VDOT, not from a number you picked on a calculator. As your fitness changes across the block, Reshape re-estimates your VDOT from the runs you actually complete and updates the next week’s paces. The taper is protected and real, not a three-day token.