Marathon Training Series

Week 3 - How Much Should You Run?

If there's one question I know almost every marathon runner eventually asks, it's this: "How many miles should I be running?" And it's a fair question. You see someone running 40 miles per week and wonder if you should be running 40. You see another runner doing 60 and start thinking maybe you aren't doing enough. Then you hear about someone running 80 miles per week and suddenly your 35-mile week doesn't seem like marathon training at all. But here's the problem: there is no magic weekly mileage number that makes someone ready to run a marathon. The right amount of mileage depends on the individual. Your current mileage matters. Your running history matters. Your injury history matters. Your schedule matters. Your ability to recover matters. And perhaps most importantly, your ability to consistently absorb the training matters.

1. Weekly Mileage Is Important

Mileage matters in marathon training. The marathon is a long event, and we need to prepare the body to spend a significant amount of time running. More running can improve aerobic development, muscular endurance, durability, running economy, and our ability to handle the demands of the marathon. But mileage is only one piece of the puzzle. A 50-mile week that includes quality workouts, a productive long run, easy recovery running, strength training, and adequate recovery can be much more valuable than a 60-mile week where the athlete is exhausted and unable to complete the important sessions. The goal isn't simply to accumulate as many miles as possible. The goal is to accumulate the right amount of mileage for you. That's an important distinction.

2. Your Current Mileage Is the Starting Point

One of the first things I want to know when determining how much someone should run is what they're running right now. If you're currently running 20 miles per week, I don't want to look at a marathon plan that says you'll be running 50 miles per week in six weeks and simply assume that's fine. Your body doesn't care what the plan says. It cares what you've been consistently prepared to handle.

3. Your Running History Matters

Current mileage isn't the only thing I look at. Running history matters too. Someone who has been running consistently for five years may be able to handle a mileage progression differently than someone who started running six months ago, even if they're currently running the exact same number of miles. Experience matters. Your body develops an ability to handle training over time. Tendons, muscles, connective tissue, bones, and your overall aerobic system adapt to consistent running. That's one reason I don't want runners making huge jumps simply because they feel aerobically capable of doing more. You might have the cardiovascular fitness to run 40 miles this week. That doesn't necessarily mean your body is ready to handle 40 miles every week. There's a difference between being able to survive a mileage increase and being able to consistently absorb it. That's what we're interested in.

4. Gradual Progression Matters

This is where the concept of gradual progression comes in. If you've been running 25 miles per week, jumping immediately to 50 probably isn't the smartest way to improve. Maybe you can physically complete the first 50-mile week. But what happens the following week? What happens after three weeks? What happens when we add a workout? What happens when the long run gets longer? What happens when you have a bad night's sleep, a stressful week at work, or a minor soreness that would have been manageable at 25 miles but becomes a problem at 50? Marathon training is not about seeing how much mileage you can handle once. It's about finding a level of training you can handle again and again and again. That's why I prefer gradual progression. We build. We observe. We recover. We build again. The goal is to arrive at peak training with a body that has adapted to the workload, not a body that's barely hanging on.

5. More Mileage Is Not Automatically Better

This is probably one of the hardest concepts for runners to accept. If 30 miles is good, why wouldn't 35 be better? And if 35 is better, why wouldn't 40 be better? Because the relationship between training and adaptation isn't that simple. At some point, additional mileage stops providing enough benefit to justify the additional fatigue. The same principle applies at higher mileage. A runner might hear that elite marathoners or advanced recreational runners are running 70, 80, or even 100 miles per week and decide they need to do the same. But mileage has to be individualized. If you can run 50 miles per week, recover well, complete your key workouts, handle your long runs, stay healthy, and continue doing that for months, then 50 miles may be incredibly productive. If you jump to 70 and suddenly your workouts deteriorate, your legs are constantly fatigued, your easy runs aren't easy anymore, and you're struggling to recover, then the extra 20 miles may have made your training worse. More mileage can create more adaptation. It can also create more fatigue. We have to find the point where the benefit is worth the cost.

6. Frequency and Mileage Are Not the Same Thing

Another important distinction is how often you run versus how many miles you run. Two runners could both run 40 miles per week but have completely different schedules. One might run four days per week. Another might run six. Neither is automatically better. Running more frequently can allow you to spread your mileage across more days, which may make individual runs shorter and easier to recover from. For example, 40 miles over five or six days can feel very different from 40 miles packed into three or four days. But frequency also has a cost. Adding another running day isn't automatically better if your schedule doesn't allow enough recovery. Again, we're looking for the combination that works for the individual. The question isn't simply: "How many miles should I run?" It's also: "How often should I run those miles?"

7. Consistency Is More Important Than One Big Week

This is one of the biggest themes I want runners to understand. One huge week doesn't make you a better marathoner. Consistency does. Let's say you normally run 35 miles per week. You decide you're going to prove to yourself that you can handle more, so you run 50 miles. Then you're exhausted. The next week you run 25. Then 20. Then 30. Then you take several days off because something hurts. You may have accumulated more mileage during that one week, but you haven't necessarily become a better-trained athlete. Now compare that with someone who runs: 35, 37, 36, 39, 38, 40, 41, 40. That's not nearly as exciting. But look at what's happening. They're training consistently. They're accumulating mileage. They're recovering. They're completing workouts. They're building durability. They're stacking weeks. And that's what marathon training is really about.

8. The Best Mileage Is the Mileage You Can Recover From

This is the key concept I want you to remember. The best mileage is the most mileage you can consistently recover from while still completing quality training. Not the most mileage you can survive. Not the most mileage your friend is running. Not the most mileage you saw on Instagram. Not the highest number you can put into your training log. The most mileage you can recover from. That's a very different thing. If 40 miles allows you to complete your workouts, long runs, easy running, strength training, and recovery while feeling reasonably good, then 40 may be an excellent training load. If 50 miles causes everything else to deteriorate, then 50 may be too much. And if 30 miles leaves you fresh enough to train consistently while you're still developing your running background, then 30 may be exactly where you need to be.

9. Mileage Has to Fit Around the Important Training

This is where mileage connects directly to what we talked about in Week 2. Your easy running exists to support the rest of the training. Mileage works the same way. Let's say your marathon plan includes a Tuesday workout and a Sunday long run. Those sessions matter. If adding another 10 miles to your week means you're too tired to execute Tuesday's workout properly and your Sunday long run becomes a survival exercise, those 10 miles may not be helping.

The goal isn't to maximize mileage at the expense of quality. The goal is to create the right training week. That means your mileage needs to support: Quality workouts, Long runs, Easy running, Recovery, Strength training, Sleep, Nutrition, Your normal life, Marathon training has to fit together. You can't evaluate mileage in isolation.

10. Your Long Run Is Part of the Mileage Conversation

We also need to consider how much of your weekly mileage is coming from the long run. A 30-mile week where 20 miles come from one long run is very different from a 30-mile week where the miles are spread more evenly throughout the week. The long run is obviously an important part of marathon training, but we don't want it to become such a large percentage of weekly mileage that the rest of the week becomes difficult to manage. Again, context matters. There isn't one perfect ratio that applies to every runner. But when I build a marathon plan, I'm looking at the entire week—not just the number at the bottom of the mileage column. The long run has a purpose. The other runs have purposes too. The goal is to make them work together.

11. You Don't Have to Add Mileage Every Week

Another misconception is that marathon training should look like a straight line upward. It doesn't. You might build for several weeks and then have a lower-mileage week. You might hold the same mileage for a few weeks before increasing. You might reduce mileage because you're fatigued. You might have a race that changes the structure of the week. You might need to adjust because of travel, work, family, weather, or life. That's all normal. Training isn't a spreadsheet where every week has to be bigger than the previous week. Sometimes the best thing you can do is hold steady. Sometimes the best thing you can do is cut back. The goal is long-term progression, not constant progression.

12. What If You're Feeling Great?

This is similar to what we talked about with easy pace last week. You have a great week. Your legs feel fantastic. Your mileage feels easy. So you think: "Maybe I should add another 10 miles." Maybe. But you don't need to make every good week a reason to increase the workload. Sometimes feeling great is the result of your training working. You don't have to immediately spend that fitness. If the current workload is producing good training, good recovery, and consistent progress, there is value in staying there. More isn't always the next step. Sometimes more of the same is exactly what your body needs to continue adapting.

13. What If Your Mileage Is Lower Than Everyone Else's?

This is another trap, especially with social media. You see someone posting their 60-mile week. Someone else ran 70. Someone else ran 80. And you're sitting there looking at your 35 miles thinking: "I'm not doing enough." But you don't know the context. You don't know their running history. You don't know how long they've been running. You don't know their recovery capacity. You don't know their injury history. You don't know what their workouts looked like. And you certainly don't know whether that mileage is appropriate for you. Your training isn't a competition with someone else's training log. Your job is to figure out what makes your training work. If 35 miles allows you to train consistently and improve, then 35 miles is valuable. There is nothing inherently impressive about running a number your body isn't prepared to handle.

14. Use Your Own Mileage Progression as Information

One of the best ways to determine appropriate mileage is to look at your own history. Imagine a runner who started their marathon build around 25 miles per week. Over time, they progressed to: 25, 28, 30, 32, 30, 34, 36, 38, 40. Notice something important. It isn't perfectly linear. There are increases. There are plateaus. There is a cutback. And eventually the athlete reaches a higher training load because they've demonstrated that they can handle it. That's the information I'm looking for. If you consistently handle 30 miles well, maybe we explore 32 or 34. If 40 leaves you exhausted for days, maybe we don't need to force 45. Your training history becomes evidence. We don't have to guess as much because we're learning what your body can actually handle.

15. Mileage Should Serve the Goal

This is ultimately how I want runners to think about mileage. Don't ask: "What's the highest mileage I can run?" Ask: "What mileage best supports my goal?" If your goal is to finish your first marathon healthy and strong, the appropriate mileage may be different from someone trying to qualify for Boston. If you're an experienced runner trying to set a personal best, your training may require a different workload than someone with limited running history. If you're coming off a lower-mileage period, we may need to build gradually. If you've already been handling high mileage for years, the conversation changes. Mileage is a tool. It's not the goal. The goal is becoming a better marathoner.

16. The Bigger Picture

This brings us back to the philosophy we've been building throughout the first few weeks. A marathon training plan isn't about maximizing any single variable. It's about putting together the right combination of training stress and recovery. Easy running gives us aerobic development without unnecessary fatigue. Workouts provide a higher-intensity stimulus. Long runs build endurance and durability. Marathon-pace work develops race-specific fitness. Strength training supports the body. Fueling allows us to train and recover. And weekly mileage gives us the volume necessary to develop the aerobic and muscular systems that allow us to run 26.2 miles.

But none of those things exist independently. The best training plan is the one where they work together. That's why I don't want runners chasing mileage for the sake of mileage. The best mileage is the most mileage you can consistently recover from while still completing quality training. If that's 30 miles, great. If it's 50, great. If it's 70, great. The number itself isn't what makes the training successful. What matters is whether you can do that training week after week, month after month, while continuing to recover, adapt, and improve. Because ultimately, marathon fitness isn't built by one giant week. It's built by stacking a lot of good weeks together. And that's how you become a marathoner.