The marathon taper, week by week.

Quick answer. A marathon taper is a planned cut in training over the last 2 to 3 weeks before the race. A 2007 meta-analysis found the most effective taper lasted 2 weeks, with training volume reduced by 41 to 60% and intensity and frequency left unchanged. In a study of more than 158,000 recreational marathon runners, strict 3-week tapers were linked to a median finish time 5 min 32 s faster than a minimal taper. The week before a marathon, run short and easy with a little race pace, rest, sleep, eat familiar carbohydrate-rich food and change nothing.

What is a marathon taper?

It is the planned easing-off at the end of a training plan. The official London Marathon beginner plan puts it simply in week 15 of 16: "The taper is here. Doing less is all about recovering from the hard training so you can stand on the Start Line ready to do your best."

The study of recreational runners, by Barry Smyth and Aonghus Lawlor in 2021, describes it the same way: "a period of reduced training load in the weeks before race-day." Its authors split tapers into strict ones, which "progressively decrease training in the weeks before the marathon", and relaxed ones, which do not.

How long should a marathon taper be?

Two to three weeks. The evidence points the same way from two directions:

• Controlled studies. The 2007 meta-analysis by Laurent Bosquet and colleagues pooled 27 studies of competitive athletes. Its conclusion: "A 2-wk taper during which training volume is exponentially reduced by 41-60% seems to be the most efficient strategy to maximize performance gains."
• Endurance athletes only. A 2023 meta-analysis of 14 studies in endurance athletes reached a similar answer: a taper of up to 21 days, with training volume progressively reduced by 41 to 60% and no change to intensity or frequency.
• Real marathon runners. Smyth and Lawlor found that "longer tapers of up to 3 weeks were associated with better performance than shorter tapers". Strict 3-week tapers did best, at a median 2.6% faster than a minimal taper. The study shows an association in logged training data, not proof of cause, and it found 64% of recreational runners used the less disciplined kind.

How much should you cut back?

Cut the volume, keep some pace. Here is how the London Marathon beginner plan does it, set against its biggest week. The plan has three runs a week. Minutes are from the plan, and the reductions are calculated.

Weeks 14 and 15 sit inside the 41 to 60% range from the research, and the faster segments stay in, which matches the advice to keep intensity. The plan's warning in week 14 is worth remembering: "Don't be tempted to do more or you will risk being tired on the Start Line." If your plan has more runs a week, keep roughly the same number of runs and make each one shorter.

What to do the week before a marathon.

Very little, on purpose. The London plan's note for the final week is "You can only do too much this week." For a Sunday race, its week looks like this:

• Monday: rest.
• Tuesday: 30-minute run.
• Wednesday: rest. Collect your number if your race has an expo.
• Thursday: 22 minutes: 5 easy, 12 at target marathon pace, 5 easy.
• Friday: rest.
• Saturday: rest. "Try to stay off your feet as much as possible today."
• Sunday: race. "Start sensibly at your Event Day pace and stick to your plan."

Use the spare time to get organised. The plan's week-15 advice is to "know your key Marathon Day timings, check the weather forecast and plan what kit you'll need." Paula Radcliffe gave the same message at a live recording of her podcast on the eve of the 2026 London Marathon, reported by Woman & Home: "Please don't anyone do anything new for the marathon. Nothing. You want to have done at least a half hour run in what you are wearing tomorrow." Paula is a co-owner of the company that makes Immufix.

How should you sleep before a marathon?

Expect the last night to be patchy, and plan the rest of the week well. In a 2015 survey of 283 elite athletes, 64% reported worse sleep in the nights before an important competition at least once in the past year. The main problem was falling asleep (82.1%), driven by "thoughts about the competition" and nervousness. The authors called it "situational rather than a global sleep problem", and found that athletes in individual sports often used relaxation and reading to cope.

The rest of race week is under your control. The NHS advice applies: "going to bed and getting up at similar times each day helps your body know when it's time to sleep", a room that is "quiet, dark and cool", and no phones or tablets for an hour before bed. Marathons start early, so it helps to make race-day wake-up time your usual time for the whole week. Our guide to how much sleep adults need has the targets.

What should you eat in taper week?

Mostly your normal food, then more carbohydrate at the end. The London plan's week-14 advice is to "increase the proportion of carbohydrate in your diet but not overall calories", which makes sense when you are running less. In the last 36 to 48 hours, total carbohydrate rises sharply. The amounts, in grams per kilo and as real meals, are in our guide to carb loading for a marathon.

For the day before, the plan says: "Stick to familiar foods that are rich in carbs, avoid spicy food and stay well hydrated." Have the breakfast you practised before long runs on race morning, at the time you practised it.

Where Immufix fits.

Keep Immufix at your usual time in taper week rather than adding anything new, which is Paula's rule for everything else too. It is one 25g scoop in around 200ml of water, once a day. Magnesium, riboflavin, niacin, pantothenic acid and vitamin B6 contribute to normal energy-yielding metabolism and to the reduction of tiredness and fatigue, and magnesium and vitamin D contribute to normal muscle function. Every amount is on the science page.

The short version.

• Taper for 2 to 3 weeks, cutting training volume by about 41 to 60%.
• Keep the same number of runs and keep some marathon-pace running in them.
• Race week is two short runs and a lot of rest: "You can only do too much this week."
• Poor sleep the night before is common. Keep regular bedtimes earlier in the week.
• Eat normally, raise carbohydrate in the last 36 to 48 hours, and try nothing new on race day.

Food supplements should not be used as a substitute for a varied, balanced diet and a healthy lifestyle. If you have a medical condition, are pregnant, breastfeeding or taking medication, speak to your GP or pharmacist before taking any food supplement.