Marathon training plan for a first-timer with a full-time job
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You can train for a first marathon on four runs a week around a full-time job, and for most people the limit is time and recovery, not fitness. The shape is one long run, one harder session and two easy runs, with the long run protected above everything else. I have not run a marathon yet. My first is London in April 2027, so this is how I am approaching it and why, not a record of having done it.
The real constraint
A marathon build asks for about four months of consistency. Fitness is rarely what stops people. A late meeting, a bad night, a child off school, and one run gets skipped, then the next. A plan that needs six good days a week has no slack for any of that.
Four runs is a number most working weeks can hold. It also leaves three days for your legs to recover from the long run.
I looked for a safe rate of weekly increase and found the evidence thinner than the advice. A 2018 systematic review by Damsted and colleagues in the International Journal of Sports Physical Therapy found very limited evidence that sudden changes in training load raise injury risk in amateur and novice runners. It found no difference between average weekly increases of 10% and 24%. That is not a licence to jump. It means nobody can hand you a number, including me.
What I do know comes from July. I ran 100km and walked the last 40, because my quads failed on the descents. It was not my lungs. Adding distance on top of a weakness you have not dealt with repeats the failure at a bigger scale, and first-timers do the same thing with volume.
What to cut first when the week collapses
Cut the second easy run first. Shorten it or drop it, and nothing much is lost.
Next, turn the harder session into an easy run. Hard running on a tired week mostly buys you a lost weekend.
The long run is the session I would protect. If the week gives you less time, shorten it instead of skipping it. A missed run is gone, so do not stack it onto the next day to make up for it.
A realistic weekly shape
Tuesday is an easy run. Thursday is the harder session, or an easy run in weeks where the plan has none. Saturday is a short easy run, and Sunday is the long run. Monday, Wednesday and Friday are off. If you lift, do the heavy leg work on Thursday after the harder run. Swap the days to suit your week, but keep the harder session at least two days away from the long run.
Easy means you can speak in full sentences. Most people run it too fast, and I wrote up how to check yours in why your easy runs aren't easy.
In the 16-week plan on this site, the first five weeks have no hard sessions beyond strides and one 5K time trial. That is deliberate. Early weeks are for getting the long run and the easy runs in without breaking anything.
That plan runs five days a week and peaks at 65km, which is more than the four-day shape above. If your week cannot hold five, drop the second easy run, not the long run. I would rather you finished on four than quit on five.
If you have a charity place
A charity place usually comes with a race date and a fundraising target, and you get little say in either. That pressure pushes people to add to the plan instead of trusting it.
I could not find a figure for how many charity runners stop training. The nearest I found is a Dutch study of 774 novices after a six-week beginners programme. Within 26 weeks, 29.5% had stopped running, and injury was the most common reason. They were beginners, not marathon runners, so read it as a warning about novices and injury, not a number for your event.
The 16-week plan on this site starts at about 50km in week one, with a 14km long run. It is written for someone already running about 45km a week with a 20km long run behind them. If that is not you yet, build up first, before week one. If your race is 24 or 25 April 2027, the London dates, count back 16 weeks and see how much time that leaves you.
Where Zonna fits
Zonna is a running app for people who tend to train too hard. It is iOS only, there is no Garmin workout export, and I am the only developer.
The 16-week marathon plan is on the site and you can read all of it before deciding anything. Full access is £7.99 a month or £59.99 a year, with a two-week trial.
You do not need an app to follow a plan. A printed plan and the talk test will do. If you want a person rather than software, I wrote about when a coach is worth paying for.
My recommendation: pick four days you can hold, protect the long run, keep the easy runs easy, and start from what you can run today.
Written by Russ Shear, who built Zonna after running 100km in July 2026 and walking the last 40 of it.