How to Train for a Marathon: Long Runs, Load and Taper

A marathon is a test of consistency more than any single workout. Around eighteen weeks of structured training lets you build volume safely, practise fuelling and arrive at the start line fresh.

Build load gradually

Increase weekly training time steadily, with a lighter week every three to four weeks. Big jumps in weekly volume are one of the most common causes of injury, especially for Masters runners.

The long run

Long runs build the endurance and durability the last 10 km demands. Progress them gradually towards around 2 h 30 to 3 h for most runners; time on feet matters more than distance. Keep most long runs easy, and include some marathon-pace segments in the final block.

Quality sessions

One or two quality sessions a week are enough: threshold intervals, steady marathon-pace runs and the occasional hill session. Everything else stays easy.

Fuelling

Practise race-day fuelling on every long run: carbohydrate every 20 to 30 minutes and a drinking plan you have tested. Never try anything new on race day.

Taper

Reduce volume over the final two to three weeks while keeping some intensity. Trust the training; the fitness is already there.

Ready to start?

The Endurance Lab 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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