Preparing for a half marathon

This week’s blog is based on an email from Shane, one of the athletes that I’ve been coaching at a tri club running session, asking for advice on preparing for a half marathon in 8 weeks time. He’s aiming to run 1.25, or 6.30 per mile.

Basic plan for the week:

Your week is going to be made up of three key runs: an interval session, a fast continuous run, and a long endurance run.

Long endurance run – I advise building this up progressively from whatever your current longest run time is, adding no more than 15 minutes per week. Build this run until you are running for 20 minutes longer than your anticipated half marathon time. (E.g., if you are looking to run 1.25, this run should get to 1.45.) Pace should feel easy to steady – a minute per mile to 1.30 per mile slower than your anticipated race pace.

Tempo run – start by running 3 miles at tempo as part of an hour long session, including time for a good warm up and a short cool down, and build this run to 9 miles by adding one mile per week. Pace should be target race pace. (Note here – don’t be disheartened if you feel cooked after 3 miles at this pace in training in week one. That’s normal. Your body will adapt each week, and on race day, ‘target race pace’ will feel a lot easier than it does in training. At least for the first six miles J )

Interval session – 30-60 minutes of hard work, with short rests, within a 60-90 minute session. Build session length slightly each week. For example, a great session is 4 x 1 mile repeats at 30s per mile faster than target race pace (for Shane, coming in on 6.00) with a minute recovery. This kind of ‘above threshold’ effort will really help the body learn to deal with clearing lactate. The minute should be just long enough to recover enough to deal with the idea of starting the next one. You can build this session by adding one repeat each week, up to a maximum of about 6 miles of hard running.

(A caveat here. Shane has been consistently attending an interval session on the track for over 3 months. If you’ve never done any ‘fast’ running, I’d replace this session with a fartlek session for the first 3 weeks, where you ‘run harder’ for a minute or two, before slowing down, then running harder again for a few minutes. This will get you used to the idea that you will recover if you slow down a bit, and you can then run hard again.)

Timing wise, keep it simple. Long run on Sunday, intervals Tuesday, Tempo Thursday gives you a sensible spacing and time for recovery rides/swims on the intervening days. Remember, there's no such thing as a recovery run!

If you have time in your week for any more run sessions (fitting around your necessary bike and swim training), I’d advise you to make them easy/steady runs of 30-60 minutes duration. Build volume by adding frequency of runs where you can before increasing the length of these extra runs. Ideally, you’ll be running six days a week for eight weeks. However, as triathletes with full time jobs, we don’t have that luxury, so treat your bike training as extra aerobic training for your legs and lungs, and keep them steady. Preparing well for the half marathon means that you’re not going to be able to hammer out two interval sets on the bike and swim each week, as well as this tough running program. Swimming sessions become free massage and recovery sessions, biking sessions become aerobic maintenance.


There you go, Shane. No pressure!


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