The Difference Between Running a Marathon and a Half Marathon

23 February 2025

Running is one of those sports that can seem pretty straightforward—just lace up your shoes, hit the road, and you're off. But when you start diving into distance running, things get a little more complicated. Two of the most popular long-distance races are the marathon and the half marathon. Sure, they both involve running long distances, but the experience of running a marathon versus a half marathon is worlds apart. From the training to the mental game, and even recovery, there’s a lot that sets these two races apart.

So, what exactly is the difference between running a marathon and a half marathon? Let’s break it down.

What Is a Marathon vs. a Half Marathon?

Before we get into the nitty-gritty, let’s clear up the basics.

A marathon is a 26.2-mile (42.195 km) race. It’s the ultimate test of endurance, stamina, and mental toughness. For many runners, completing a marathon is the pinnacle of their running goals.

A half marathon, as the name suggests, is half the distance of a full marathon, clocking in at 13.1 miles (21.1 km). While it’s still a significant physical challenge, the half marathon is often seen as more accessible and achievable for a wider range of runners.

But as you’ll see, the differences extend far beyond just the number of miles. Let’s take a closer look at how these two races stack up against each other.

The Training Commitment: Time and Intensity

Let’s face it—training for a marathon is a big, big commitment. If you’re planning to run a full marathon, prepare to spend months of your life gearing up for race day.

Marathon Training

Training for a marathon typically takes 16-20 weeks of consistent running. And we’re not talking about casual jogs a couple of times a week. Marathon training requires running 4-6 days a week, including long runs on weekends that can stretch 16-20 miles (or more) as you get closer to race day.

The training intensity is high. You’ll need to build your mileage slowly but steadily, and you’ll also need to focus on speedwork, tempo runs, and recovery runs. Plus, you’ve got to factor in cross-training, strength training, and rest days to keep your body from breaking down.

A key part of marathon preparation is the long run. These are weekly runs that build endurance and teach your body how to handle prolonged physical stress. If you’ve ever heard someone say, “The marathon really starts at mile 20,” they’re not kidding. The last 6.2 miles can be brutal, and your long runs help you prepare for that.

Half Marathon Training

In contrast, training for a half marathon is definitely more manageable. Most half marathon training plans last 10-12 weeks and require running 3-4 days a week. While you’ll still need to do long runs, speedwork, and tempo runs, the overall mileage is much lower.

For a half marathon, your long run will max out around 10-12 miles, which is significantly easier to fit into a busy schedule than a 20-mile run. The time commitment is less intense, and there’s generally more flexibility in fitting your training around your other responsibilities.

Key Difference: Time Commitment

The bottom line? Training for a marathon is a full-time job. You’ll be spending hours each week on the road, and your social life will probably take a backseat. Half marathon training, on the other hand, is more forgiving. It’s still a challenge, but it’s much easier to balance with the rest of your life.

The Mental Game: Endurance vs. Speed

Running is as much a mental challenge as it is a physical one, and marathons and half marathons test your mental toughness in very different ways.

The Marathon Mental Battle

Running a marathon is a true test of endurance, not just physically but mentally. You’ll spend hours on the road, and during that time, your mind will have plenty of opportunities to play tricks on you. There will be moments when you feel invincible, but there will also be times when you want to quit.

The biggest mental hurdle in a marathon is the sheer amount of time you spend running. You’ve got to keep your mind engaged and focused for 3, 4, or even 5+ hours. And remember, the first 20 miles are often called “the warm-up” for good reason. The last 6.2 miles are where the real battle begins.

The Half Marathon Mental Game

The mental game for a half marathon is different. Since the race is shorter, you won’t be out there as long, so the mental fatigue isn’t as severe. That said, you’ll still need to dig deep, especially in the later miles when your legs start to get tired.

In a half marathon, your focus may be more on pacing and speed. You can push yourself a bit harder because you know the finish line isn’t too far away. But don’t let that fool you—there’s still plenty of mental toughness required to keep a consistent pace and avoid burning out too soon.

Key Difference: Mental Fatigue

In a marathon, the mental battle is all about enduring for a long period of time. You’ll have to keep yourself motivated for hours. In a half marathon, while there’s still mental fatigue, it’s more about pacing and staying focused for a shorter period.

Physical Demands: Pacing vs. Pounding

Let’s not sugarcoat it—both marathons and half marathons are tough on your body. But the physical demands of each race are quite different.

Marathon Physical Demands

In a marathon, it’s all about endurance. You have to pace yourself smartly from the very beginning. Go out too fast, and you’ll hit the dreaded “wall” around mile 20, where your body runs out of glycogen, and you feel like you can’t move another step.

Marathon runners have to be strategic with their energy expenditure, nutrition, and hydration. You’ll be burning through a lot of fuel, so taking in enough calories during the race is essential to avoid bonking. Your muscles will take a pounding, especially in the final miles, and your legs will feel like lead.

Half Marathon Physical Demands

In contrast, the half marathon allows for a bit more speed. You can push yourself harder because you don’t have to conserve as much energy. Pacing is still important, but you won’t need to worry as much about hitting the wall.

That said, running 13.1 miles still requires proper fueling and hydration. You’ll need to keep your body adequately nourished to perform your best, but the physical toll on your body is much less severe compared to a full marathon.

Key Difference: Energy Management

The biggest physical difference is in how you manage your energy. In a marathon, it’s a slow burn. You have to pace yourself and conserve energy for the long haul. In a half marathon, you can push harder and run faster, knowing that you won’t be out there for as long.

Recovery: Post-Race Blues and Bounce Back

The aftermath of a race can tell you a lot about the difference between a marathon and a half marathon. Recovery time is a big factor, especially if you’re planning to run multiple races.

Marathon Recovery

Marathon recovery can take weeks, if not months. Your muscles, joints, and tendons will need time to heal from the pounding they took during the race. It’s common to feel sore for several days (hello, DOMS—delayed onset muscle soreness), and you may need to take a full week off from running just to let your body recover.

Many marathon runners also experience a post-race emotional crash. After spending months preparing for one monumental day, it’s natural to feel a bit lost once it’s over.

Half Marathon Recovery

Recovering from a half marathon is much quicker. You’ll likely feel sore for a day or two, but most runners can bounce back and resume light running within a few days. The emotional toll is also easier to manage since the race is shorter, and the time commitment is less intense.

Key Difference: Recovery Time

The recovery time for a marathon is significantly longer than for a half marathon. If you’re someone who enjoys racing frequently, a half marathon may be a better option since you can recover faster and get back out there sooner.

Which Race Is Right for You?

Ultimately, the decision between running a marathon and a half marathon comes down to your personal goals, fitness level, and lifestyle.

If you’re someone who loves a challenge, has the time to commit to months of training, and is looking for the ultimate test of endurance, then a marathon might be the perfect goal for you.

On the other hand, if you’re looking for a race that’s still challenging but more manageable in terms of training and recovery, the half marathon could be right up your alley. It’s still a significant accomplishment, but it’s more accessible for runners with busy schedules or less experience.

No matter which race you choose, the most important thing is to enjoy the process. Both marathons and half marathons offer incredible experiences, a sense of accomplishment, and the chance to push your body to new limits. Whether you’re running 13.1 miles or 26.2 miles, the finish line is always worth it.