The Essentials of Peak Week For Marathon Training

The peak week of marathon training often feels like the hardest week. You have already been increasing mileage and doing long runs for weeks, and then you have one final push before the taper. Some runners make peak week harder than needed by excessively piling up mileage or tackling workouts that are too challenging. As a certified running coach, I have worked with hundreds of runners through successful marathon peak weeks. This article will guide you through what a peak week is, how to approach it, and how to recover from it so you can go into your best marathon race day. 

What is peak week?

Peak week is a term used to describe the most intensive weeks of marathon training. Peak week typically involves your longest long run, biggest workouts, and highest weekly mileage for marathon training – hence the name “peak.” The peak week in marathon training is timed about two to three weeks before the race – or right before you start the taper. 

Peak week should be built upon all the weeks of training leading up. You do not want to make huge increases in mileage or intensity that you have not prepared for. For example, if you have averaged 45 miles per week, you do not want to increase to 60 miles in your peak week. 

Peak week itself is not magical – it does not necessarily matter more than the entire training block. Some runners overemphasize peak week and push too hard in that week. However, that approach can cause them to be too fatigued going into the taper. 

Not overemphasizing the peak week does not mean it is entirely unimportant. Typically, the peak will include your longest runs and your hardest workouts (such as marathon pace tempos). Peak week is designed to apply one more hard week of training, before you start to taper and sharpen before the race. 

Related: How Far Should You Run Before a Marathon?

Your weekly mileage for marathon training will vary

The peak week will look different in various training plans. Typically, the peak week occurs two to three weeks before the marathon. Based on how many weeks you train for a marathon, this may be around weeks 12 to 16 of training. 

A first-time marathon runner will prioritize mileage and the long run in their peak week of marathon training. Since they are preparing for the marathon distance for the first time, the mileage will be challenging even if all runs are at an easy pace.

For example, if a first-time marathon runner averaged 35 miles per week, they may increase to 37-39 miles in their peak week. The longest run of training would occur during this week. For a first-time marathon runner, the longest run would be 17-20 miles (depending on ability and training). 

A sample peak week for a beginner:

• Monday: easy run
• Tuesday: easy run + strides
• Wednesday: rest
• Thursday: easy run 
• Friday: cross-train
• Saturday: 18 mile long run
• Sunday: rest

Intermediate and experienced marathon runners will approach peak week differently. The mileage alone is not a challenge for these runners. As a result, they will focus on both mileage and intensity in their peak week. A peak week may include a 20-22 mile long run and an intense workout such as a long tempo run at marathon pace. 

A sample peak week for intermediate/advanced:

• Monday: easy run + strides
• Tuesday: 8 miles at marathon pace 
• Wednesday: easy run
• Thursday: rest or cross-train
• Friday: easy run + strides
• Saturday: 22 mile long run
• Sunday: rest

Once you complete your peak week, you start the marathon taper. Read this full article for a breakdown of how to taper for a marathon, based on the most recent science. 

Tips for Managing Peak Week

The peak week in marathon training is a mentally and physically demanding block. You devote a significant chunk of time and energy to your training that week. More than likely, you will feel fatigued from the training load. However, you don’t want to run yourself into the ground in peak week. It is essential to recover well so that your body absorbs training and you aren’t overcooked before your marathon. 

Smart recovery practices may seem like extra work, but they are worth the deliberate effort. You will feel better during the last week of marathon training – and you will adapt well to your training so you go into race day at your fittest. 

Ensure you eat enough

Even short-term deficits in energy availability can negatively impact your training and performance. A 2023 randomized controlled trial published in the Journal of Physiology demonstrated that even 10 days of low energy availability downregulated muscle protein synthesis in trained female athletes. The researchers concluded that training adaptation, metabolic rate, and muscle mass all could suffer from even 10 days on inadequate energy intake. 

Low energy availability can easily occur unintentionally during the peak week of marathon training. Endurance training alters hunger hormones to make you feel less hungry—even while your energy needs are skyrocketing. You cannot rely on hunger alone during marathon peak week. Instead, you need to eat based on your activity level, even if you are not hungry. 

Your exact energy needs will be based on your training load and body size. You can use a visual guide such as the Athlete’s Plate or guides from Featherstone Nutrition to help estimate your energy needs. If in doubt, increase your carb intake during peak week. 

Practice your race day fueling

As noted above, you typically will run your longest run of marathon training during peak week. Whether you do 18, 20, or 22 miles, this run will provide the opportunity to rehearse your marathon day nutrition strategy. Eat your planned pre-race breakfast before the long run and then take your carbohydrates and hydration just as you plan to on race day. 

You can also practice your race day fueling in any marathon pace workouts during race week. This approach allows you to ensure you can tolerate your fuel during prolonged durations at race pace. Since intensity can trigger GI upset for some runners, this approach helps you feel confident that you can stomach your gels at marathon pace on race day. 

Related: The Best Running Gels for Sensitive Stomaches

Prioritize sleep 

Your training is only as good as your recovery. Nutrition is one of the best recovery tools, along with sleep. In addition to eating enough during peak week, you want to get enough sleep during that week. 

Most runners need 7-9 hours of sleep per night. You may find that you need extra sleep during peak week compared to other weeks. Build your peak week so that you can still get enough sleep. Extra mileage is not worth it if you have to sacrifice sleep and recovery. 

Slow down your easy runs

The higher volume and intensity of the last week of marathon training before the taper can be fatiguing. As a result of training fatigue, you may notice that you need to run slower on your easy runs. And that’s okay! It is better to slow down your easy runs during peak week, as this approach allows you to put forth quality effort on your long runs and marathon pace workouts. You are not losing fitness – you are just experiencing temporary fatigue from training. 

Marathon peak week can feel intimidating and exhausting. However, with the right approach to your training plan and recovery approach, you can complete peak week while feeling confident and ready for your race. 
Want more marathon training advice? Listen to the Tread Lightly Podcast on your favorite podcast app!