What to do in the week before your marathon

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You’ve done the work. The 20-milers are behind you. The long Sunday runs, the early alarms, the legs that wouldn’t work on Tuesday because you ran too hard on Sunday — all of it is banked. The week before your marathon is not the time to add to that account. It’s the time to protect it.

This is also the week most runners quietly panic and make bad decisions. They suddenly feel sluggish from tapering and convince themselves they’re losing fitness. They do an extra run “just to stay sharp.” They try a new pasta dish the night before because they heard carb-loading matters (it does, but not like that). These are the mistakes that cost you on race day — not your training.

What follows is a practical, day-by-day breakdown of what to actually do in the seven days before your marathon: how much to run, what to eat, what to check, and how to handle the head games that come with it.

Your mileage this week: less than you think

If you’ve followed a structured plan — something like a 16-week marathon training plan for beginners — your taper will already have started 2–3 weeks out. The final week is the sharpest reduction of all.

Total weekly mileage in the final week should be around 30–40% of your peak training week. If your biggest week was 55km, you’re running roughly 17–22km across the whole week. That’s it.

Here’s a rough template for what that looks like:

The strides on Tuesday are worth doing — a few 20-second pick-ups at close to 5K effort (not sprinting) remind your legs what fast feels like without fatiguing you. Keep every other run conversational. If you find yourself breathing hard, slow down.

The taper dread is real — don’t let it trick you

Almost every runner who tapers properly feels terrible. Heavy legs, low energy, a strange flatness. You’re not losing fitness. Your body is storing glycogen, repairing tissue, and consolidating the adaptations from months of training. It takes about 10–14 days to fully absorb a heavy training load — and your taper is doing exactly that.

Marathon taper week: what to expect and how to handle it goes into this in more detail, but the short version is: feeling sluggish during taper is a sign the process is working, not a sign you’re unprepared.

Don’t add extra miles. Don’t do a “confidence run” of 16km on Wednesday because you’re anxious. That run will not help you — it will take something from you that you needed on Sunday.

Carbohydrate loading: what it actually means

Carb-loading is not eating one big bowl of pasta the night before your race. That’s a decent dinner. Real carbohydrate loading means spending 2–3 days systematically increasing your carbohydrate intake to top up glycogen stores — your primary fuel source for anything over about 90 minutes of running.

From Thursday through Saturday, aim for roughly 8–10g of carbohydrate per kilogram of body weight per day. For a 70kg runner, that’s 560–700g of carbs daily — more than most people eat. Spread it across meals: porridge, rice, pasta, bread, bananas, potatoes. Reduce fibre and fat slightly to make room and minimise GI issues on race day.

Carbohydrate loading before a marathon: how to do it right covers the science and the practical detail — worth reading properly before you plan your meals.

What you eat the night before matters less than what you eat in the two to three days prior. Keep dinner familiar, moderate in size, and early enough that you’re not still digesting at bedtime. Pasta, rice or potato with a simple protein source is fine. Not a new restaurant. Not a heavy sauce you’ve never tried before.

Race-day logistics: sort this before Saturday

Nothing drains mental energy like logistics anxiety on race morning. Get this sorted by Thursday so your head is clear going into the weekend.

Things to confirm and prepare:

• Race number and chip — know where they are, check they’re correct
• Kit — lay it out completely. Shoes, socks, shorts, vest/top, watch, GPS charged. Nothing new on race day. No new shoes, no new socks, no new shorts. Wear what you’ve trained in
• Gels and fuel — if you’ve been practising with specific gels during training, have them ready. Know the aid station locations on the course
• Travel and timing — how are you getting there? When do you need to leave? Add 30 minutes of buffer. Bag drop queues and toilet queues at marathons are always longer than you expect
• Weather check — check the forecast Thursday and again Saturday. Dress accordingly, not optimistically. If it’s cold at the start, an old long-sleeve you can discard at mile 2 is worth it

If you’re racing somewhere unfamiliar, a brief look at the course profile is useful — knowing where the hills are between miles 18–22 is more useful than discovering them on tired legs.

Sleep: realistic expectations

You will probably not sleep well the night before your marathon. That’s normal, and it won’t ruin your race. Research consistently shows that one night of poor sleep has minimal impact on endurance performance — what matters more is the accumulated sleep from the whole week.

So: prioritise sleep from Monday to Friday. In bed by 10pm, phone away, dark room. If you sleep badly on Saturday night, accept it and don’t catastrophise. Hundreds of thousands of runners have run good marathons on 4 hours of pre-race sleep.

What does tend to help: stop caffeine by early afternoon on Saturday if you’re caffeine-sensitive. Don’t have alcohol the night before — it fragments sleep and dehydrates you. Keep your evening calm.

What to avoid this week

This list might be more important than anything above:

• New shoes — even a half-marathon in new shoes can cause blisters. Don’t do it
• New foods — no exotic meals, no high-fibre experiments, nothing your gut hasn’t seen before
• Extra mileage — it won’t help. Any fitness gain from a long run takes 10+ days to show up
• Standing for hours — if you go to the race expo to collect your number, don’t spend three hours wandering around. Get in, get out, go home and sit down
• Alcohol — even one or two drinks mid-week disrupts sleep quality and slows glycogen storage
• Illness exposure — this sounds paranoid until you catch a cold four days before your race. Wash your hands. Avoid crowded spaces if you can

One more: don’t spend hours on race forums reading about other people’s strategies. You have your plan. Stick to it.

The mental side: this is normal

Doubt in the final week is almost universal. You’ll question whether your long runs were long enough, whether you trained hard enough, whether you should have done more speed work. You probably can’t answer those questions honestly right now — and it doesn’t matter. You cannot change your fitness level in seven days.

What you can do is control the week well. Research from the British Journal of Sports Medicine suggests that confidence in your preparation correlates with better race-day performance — not because belief is magic, but because anxious runners go out too fast, abandon their fuelling plan, or make reactive decisions that cost them in the second half.

Trust your training. Trust the process you’ve been following. A well-executed average race day will beat a panicked one every time.

The honest takeaway

1. Run less than feels comfortable. Total mileage this week should be 30–40% of your peak week. If it feels like not enough, that’s probably right.
2. Carb-load properly from Thursday. 8–10g of carbs per kg bodyweight per day for 2–3 days — not just one big pasta dinner Saturday night.
3. Sort your logistics by Thursday. Travel, kit, gels, number, weather. Nothing new on race day — no new shoes, no new food, nothing untested.
4. Poor sleep on Saturday night is normal and won’t wreck your race. Focus on sleeping well Monday to Friday instead.
5. The heavy, flat feeling during taper is your body recovering — not falling apart. Don’t add extra runs. The work is done. Your job this week is to show up fresh.

Next read: How to pace yourself in your first marathon