Half Marathon training plan,
on your Garmin.
The half marathon is the distance where training starts to look like a system rather than a set of runs. It is long enough to demand real weekly volume and a genuine long run, but short enough that it does not take over your life the way a marathon does. For a lot of runners it is the sweet spot.
What a half marathon week looks like
Build length: 12 to 14 weeks
Weekly volume: 50 to 80 km a week
Four to five runs. A long run building to 18 to 20 km, one threshold or tempo session, one easy-to-moderate mid-week run of decent length, the rest easy.
The session that decides your half marathon
Sustained tempo. A continuous 20 to 40 minutes at around half marathon effort, which teaches you to hold a strong pace when it stops being comfortable.
The mistake almost everyone makes
Fuelling for a half marathon
This is where fuelling starts to count. Most runners want something around 45 to 60 minutes in. Practise it on long runs, because race day is the wrong time to find out your stomach disagrees.
Which Garmin metrics actually matter here
- Training load, to see whether weekly volume is actually rising
- Lactate threshold pace, which sits close to half marathon effort
- HRV status and Body Battery, to catch the cumulative fatigue
- PacePro or equivalent, for a pacing plan that accounts for hills
How to get this plan onto your watch
- Free option, Garmin Coach: covers 5K, 10K and half marathon plans and pushes each workout to the watch. There is nothing for the marathon or ultra distances, and none of it is built around your specific race date.
- Adaptive option, Custom Gains: say your race and date in plain English. It reads your Garmin history, builds the half marathon block around your actual fitness, and pushes each session to the watch, reshuffling the week when you miss days or your recovery drops.
Want this half marathon plan built for you?
Tell the coach your race and your date in plain English. It reads your Garmin, builds the week, and pushes every session to your watch.
Build my half marathon planSet it up on your watch
- Forerunner 265 training plan
- Forerunner 570 training plan
- Forerunner 955 training plan
- Fenix 7 training plan
Useful free tools: race time predictor · heart rate zone calculator · overtraining check.
FAQ
How long does it take to train for a half marathon?
Twelve to fourteen weeks from a base of regular running. From a standing start, give yourself longer and build the base first.
How long should my longest run be before a half marathon?
Around 18 to 20 km. You do not need to cover the full distance in training. Race day adrenaline and taper freshness cover the gap.
Do I need to eat during a half marathon?
Most runners benefit from taking something around 45 to 60 minutes in. Practise it in training rather than trying it for the first time on race day.
How many days a week should I run for a half marathon?
Four to five. Below four it is hard to build enough weekly volume to race the distance rather than survive it.