The half marathon is long enough to need real endurance and short enough to race hard. Most runners need around fifteen weeks to prepare well, building on a base of regular running.
The long run
The weekly long run is the backbone of half marathon training. Build it gradually, by roughly 10 to 15 minutes at a time, towards 1 h 45 to 2 h 15 depending on your level. Keep most of it easy; later in the plan, finish some long runs with a few kilometres at goal pace.
Threshold work
Half marathon pace sits just below your threshold, so threshold sessions are the most specific quality work you can do. Examples are 4 × 8 minutes or 2 × 15 minutes at a comfortably hard effort.
Keep easy days easy
Around 80% of your running should feel conversational. That is what lets you recover for the long run and the quality session each week.
Fuelling and strength
Practise taking carbohydrate on long runs so race day holds no surprises. Two short strength sessions a week reduce injury risk as volume rises.
Taper
Cut volume over the last 10 to 14 days while keeping short race-pace efforts. You should arrive feeling fresh, not flat.
Ready to start?
The Endurance Lab half marathon training plans come in four levels (Start, Develop, Perform and Podium) with heart rate, pace, power or RPE versions where available. Use Find your plan to filter by level, the hours you have each week and the weeks until your race. New to training by effort? Read our RPE guide and training zones guide first.
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