Your first half marathon: how to prepare

1:59:30. Four figures that changed the running world. At the 2026 London Marathon, Kenyan Sabastian Sawe became the first person to break two hours in an official race. What Eliud Kipchoge achieved in Vienna in 2019 only under laboratory conditions is now part of the official record books.

This is where it gets interesting: Sawe’s pace was around 2:50 minutes per kilometre. For comparison, if you finish your first half marathon at 6:30 per kilometre, you are running at less than half the speed of the fastest man in the world. Sounds sobering? It is not. It shows what sport really is: a broad spectrum, and you are not racing the world’s elite.

Your half marathon is not Sawe’s marathon. It is your personal world record. That is what this guide is about.

The 21.1 kilometres are not Europe’s most popular race distance by accident. A half marathon is long enough to be a real challenge, yet short enough to train for alongside work, family and sleep.

A marathon often calls for 18 to 20 weeks of training and several runs lasting more than three hours. For a half marathon, 12 weeks and one 90- to 120-minute long run at the weekend are often enough. That is also why half-marathon events are booming: Hamburg, Mainz, Berlin and Vienna often sell out months in advance.

And honestly, crossing a half-marathon finish line changes how you see your body. That is simple physiology.

Before the training plan comes an honest check. A half-marathon plan only works if you bring a base with you. Otherwise, your tendons, bones and motivation can all become overloaded in the first two weeks.

As a beginner, you should be able to run 10 kilometres continuously or 60 minutes comfortably without your breathing falling apart. If you are not there yet, that is no disaster. Add an eight-week build-up first and plan for 20 weeks rather than 12.

A good half-marathon plan rests on three building blocks: easy runs, a long run at the weekend and a moderate tempo session or fartlek. That is enough. More can easily be too much for a beginner.

The logic is simple: easy runs develop your aerobic base, capillaries and tendons. The long run prepares your mind and legs for the distance. The tempo session makes you faster, but it is a bonus on top of the foundation.

In the final two or three weeks before race day, reduce your volume by 30 to 50 per cent. This is called tapering, and it is where many first-timers get nervous. Trust the plan: fresh legs matter more on race day than an extra 18 km three days beforehand.

If you take away one tip from this article, make it this: run the second half faster than the first. This is a negative split, the strategy many top marathoners use for personal bests, including Sawe in London.

The reason is simple: you start with adrenaline, fresh legs and full glycogen stores. Go out too fast and you pay for it twice over after kilometre 16. Runners call that the wall. Start the first 10 kilometres deliberately slower, then pick up the pace in the second half. You will usually reach the finish more comfortably and often faster.

A practical rule: run the first 10 km 5–10 seconds per kilometre slower than your target pace. It feels unnaturally slow at the start. That is the point. Work out your target pace beforehand with our Pace and finish-time calculator.

Training only works with recovery. It sounds obvious, but this is where many beginners struggle. If you run two or three times a week, you need rest days between sessions. Otherwise planned training stimuli turn into creeping overload.

For food, the rule is simple: nothing new on race day. Test what your stomach tolerates in training, whether that is a banana, bread with honey, muesli or porridge, and eat the same on race day. Trying energy gels or a new sports drink for the first time during the race is a reliable way to discover the course toilets.

One final note: tapering means running less. It does not mean stopping completely. Short, easy sessions in the final 10 days keep your legs fresh. Complete rest can leave them flat. Trust the process.

Three things decide race day, and none of them is talent. First, pace: start slowly. Really slowly. If runners who later collapse overtake you in the opening kilometres, you are doing it right. Second, fuelling: eat a familiar, carbohydrate-rich meal 2–3 hours before the start. Drink at aid stations during the run, not constantly but regularly.

Third, your mindset. Kilometres 14 to 18 feel hard for most first-timers. That is normal. Prepare a few mantras: “Three more songs.”, “To the next bridge.”, “I am running for myself.” It may sound a little esoteric, but it works. Ask anyone who has finished a half marathon.

Then comes the finish line. Take a photo. Be proud. Think about the second half, perhaps even a marathon. But first: recover.