How to Taper for a Marathon or Half Marathon

What a taper actually does

A taper is the window where fatigue drops faster than fitness, and the training you have already banked finally shows up in your legs. You are not building anything new in the last three weeks before a marathon. You are letting the adaptations from the previous 16 to 20 weeks land.

The research is consistent across decades. Mujika’s taper meta-analyses, Pfitzinger’s marathon templates, and Daniels’ running formula all converge on the same pattern. Volume drops significantly. Intensity is maintained. The taper window sits between 8 and 14 days of active reduction, with the total volume cut landing in the 41 to 60 percent range for most trained runners.

Get this right and you arrive on the start line with more performance capacity than you have had all cycle. Get it wrong in either direction, too much rest or not enough, and the months of work cash out at 90 percent.

The volume-intensity split

This is the rule that matters most and the one most hobbyist runners break. Volume comes down. Intensity stays where it was.

If your peak week was 80 kilometres with a threshold session and a long run with marathon-pace segments, your taper weeks still contain threshold work and still contain marathon-pace efforts. The sessions are shorter. A 6 x 1km threshold becomes 4 x 1km. A 32km long run with 16km at marathon pace becomes a 22km long run with 10km at marathon pace.

Cutting intensity is what makes people feel flat on race day. Your neuromuscular system needs to keep firing at race speeds right up to taper week. Stop running fast and your legs forget how. Keep running fast at reduced volume and you stay sharp while shedding fatigue.

A sample 3-week marathon taper

Assume a peak week of 80km with two quality sessions and a long run. Race is Sunday of week 3.

Week 1 (three weeks out): 65-70km, roughly 80 percent of peak

• Monday: rest or 30 min easy
• Tuesday: 12km with 5 x 1km at threshold, 2 min recovery
• Wednesday: 10km easy
• Thursday: 8km easy with 6 strides
• Friday: rest
• Saturday: 26km long run with 12km at marathon pace
• Sunday: 8km recovery

Week 2 (two weeks out): 50-55km, roughly 65 percent of peak

• Monday: rest
• Tuesday: 10km with 4 x 1km at threshold, 2 min recovery
• Wednesday: 8km easy
• Thursday: 6km easy with 6 strides
• Friday: rest
• Saturday: 18km with 6km at marathon pace
• Sunday: 6km recovery

Week 3 (race week): 30-35km, roughly 40 percent of peak, race included

• Monday: rest or 4km very easy
• Tuesday: 8km easy with 4 x 400m at 10k pace, 90 sec recovery
• Wednesday: 6km easy with 4 strides
• Thursday: rest
• Friday: 4km easy
• Saturday: 3km shakeout with 2 x 200m at marathon pace
• Sunday: race

A sample 2-week half marathon taper

Halves need less taper because the training block builds less absolute fatigue. Assume a peak of 60km.

Week 1 (two weeks out): 45-50km, roughly 75 percent of peak

• Monday: rest
• Tuesday: 10km with 4 x 1km at threshold
• Wednesday: 8km easy
• Thursday: 6km easy with 6 strides
• Friday: rest
• Saturday: 16km with 8km at half-marathon pace
• Sunday: 6km recovery

Week 2 (race week): 25-30km, race included

• Monday: rest
• Tuesday: 8km with 4 x 600m at 10k pace
• Wednesday: 5km easy with 4 strides
• Thursday: rest
• Friday: 4km easy
• Saturday: 3km shakeout with a few 20 second pickups
• Sunday: race

Taper tantrums are normal

Somewhere in week two the strange sensations start. Legs feel simultaneously heavy and hollow. Sleep gets choppy for no obvious reason. Mood drops. Niggles appear in muscles that have been fine all block. You become convinced you have lost fitness.

You have not. Your nervous system has been carrying months of accumulated stress and the reduction in training load forces a recalibration. Cortisol drops. Inflammation settles. The body re-sensitises to sensations you have been ignoring.

The mistake is to treat the weirdness as a signal to add training. It is not. It is the taper working.

What most people do wrong

Too much rest. Cutting to two runs in race week and doing them both at jogging pace. The legs go dead. Keep the frequency close to normal. Drop the duration instead.

Too much fussing. New shoes, new foam roller routine, new breathing drill, new carb strategy. Race week is for executing what you have already rehearsed. If it is not in your long-run notes from the block, it does not belong in race week.

New foods. The single most common cause of a marathon going sideways is a race-morning breakfast that was not tested in training. Your pre-long-run meal is your race breakfast. That is the whole rule.

Sleep panic. The night before a race is often poor. The night that matters is two nights before. Prioritise sleep hygiene from the Monday of race week and stop measuring the night before.

Race-week carb loading

For a marathon, target 8 to 10 grams of carbohydrate per kilogram of body weight per day for the 36 to 48 hours before the gun. For a 70kg runner that is roughly 560 to 700 grams of carbs on Friday and Saturday.

For a half marathon, one solid carb-focused day on Saturday is enough. You are not running long enough to fully deplete glycogen, so the aggressive two-day load is unnecessary.

Practical rules. Favour low-fibre, low-fat carb sources you have used during training. White rice, white bread, pasta, potatoes, sports drinks, bananas. Drop vegetables and heavy protein on the Saturday. Hydrate with electrolytes, not plain water.

Race-day essentials

Nothing new. Same shoes you did the long runs in. Same breakfast you ate before long runs. Same fuelling strategy, same carb grams per hour, same gels or chews. Same clothing tested in heat or rain depending on conditions.

Warm up shorter than you think. For a marathon, 5 to 10 minutes easy with a few strides is plenty. For a half, 10 to 15 minutes with a short pace pickup. The first few kilometres of the race will finish the job.

How Pelaris handles the taper

Tapering is one of the places where having the program handle the math pays off. Pelaris builds the taper into the final two to three weeks automatically when you set a goal race date in your endurance or marathon program. Volume drops on schedule. Intensity is held. The sessions you see in the last three weeks are shorter versions of the quality work you have been doing all block, not invented novelty.

The AI coach adapts the taper to what your body is telling it. Daily check-ins and the workout tracker feed readiness signals back into the plan. If recovery is lagging coming into taper, the coach can pull the taper forward by a few days so fatigue clears in time. If you arrive at taper feeling fresh and worried about going stale, it can hold the intensity a beat longer before dropping volume. This is the kind of decision that is awkward to get right in a spreadsheet and easy to get right when the plan is living.

The Engine Room shifts its surface as race day approaches. Prepare-category content, warm-up protocols, race-day checklists, carb-loading guides, pace calculators, gets promoted over general training resources in the two weeks before the race. You are not hunting through the app for what matters. It is already in front of you.

And the tracker logs every taper session so you can watch the volume drop week by week. Seeing the line trend down is reassuring during taper tantrums. The work is banked. The graph confirms it.

For more on why the process metrics matter more than the feelings during this period, see this piece on measuring what actually drives progress.

The habit worth building

Trust the taper. The training is done. The fitness is banked. Your job in the final three weeks is to show up on the start line with less fatigue than you have had in months, not to cram one more long run or one more tempo because the legs feel weird.

Run the sessions on the page. Eat the food you have tested. Sleep as well as you can. Ignore the noise in your head. The race will handle the rest.