Four weeks out: what your half marathon is really for...

Hi Reader,

In the spring of 1983, a few weeks before London, I flew to Rome for what I'd been told was a half marathon. It turned out to be 28km.

I'll come back to that. First, the reason it's on my mind.

The autumn marathon season now stretches from Sydney in late summer to Valencia in December. As those races have grown, so has the number of shorter races runners build into their plans. The half marathon is the go-to, usually four or five weeks out, and right now a lot of the runners I coach are racing one ahead of October marathons.

Pace it or race it?

Plenty of runners use their half to practise marathon pace, controlling it all the way. That does teach your body what marathon pace feels like. But is that enough return for the cost of entry?

Holding marathon pace to what would only be halfway in a marathon teaches you nothing about the resilience you need in the last 10km. At this stage it should feel relatively comfortable anyway. If it doesn't, your marathon pace needs a rethink.

A race also teaches something training can't: the skill of racing.

So I'm telling everyone I coach the same thing: race it.​
​Push yourself and find out how fit you actually are.

So far, those who've raced have run PBs or near-PBs, and most finished strong. That doesn't mean they could have gone faster. It means they held a fast pace without fading at the end, and that lets you make a reasonable estimate of your marathon pace.

• You finished strong: set your marathon pace with confidence.
• You faded late, even with a PB: dial your target down.

📊 Did you fade? Check your splits​
After your tune-up half, open your watch data and compare your pace over the last 5km with your first 10km. If you slowed noticeably, you faded, even if you ran a PB. That's your cue to ease your marathon target back a notch.

Back to 1983

We didn't have many half marathons back then. The standard UK race was 10 miles, and there were plenty of them.

In January I won the Sittingbourne 10 in 48:30, which was my fitness at that point in the season. In March I won the Tonbridge 10 in 47:11, a PB, pulling away from 2:13 marathoner Paul Eales all the way.

Then came Rome. I finished a very close second to Bernie Ford, a 2:10 marathoner and Olympic 10,000m finalist, and ahead of Italy's 2:11 man Marco Marchei. We went through halfway in about 63 minutes. I held the pace all the way to the finishing straight, where Bernie's 10k speed edged him clear.

Going all-out four or five weeks before a marathon is a risk. But my PB was 2:12:06, and after those races I was confident 2:10 was possible. I won London in 2:09:43.

Would I have finished in 2:12 if I'd run those races at 2:12 practice pace? Impossible to know. What I do know is that stretching myself to the limit, and coming out feeling strong, reminded me what battling fatigue is like, physically and mentally. Most importantly, it gave me belief.

🏋️ Bonus workout: your half marathon week

• Tuesday: 20 min easy, then 3 x 2km at half marathon pace with 90s jog recoveries
• Thursday: 40 min easy plus 6 x 20s strides
• Saturday: 20 min shakeout
• Sunday: Race. Settle for the first 5km, then go.
• After: 3 to 4 easy days before your marathon sessions resume

Racing a half this autumn? Hit reply and tell me your time and how the last three miles felt.

All the best,
​Mike Gratton (Head Coach, Coach the Run) & the team.

p.s. I'm organising the Basingstoke Half Marathon, 10k and 5k on
4th October 2026. Runners make the best volunteers because you know what it's like out there. If you're local and can help, email: elizabeth.spencer@destinationbasingstoke.co.uk​

p.p.s. Read my latest Ask the Coach blog:

​What should I eat before an early parkrun?​

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