Can You Train for a Marathon and Build Muscle?


People run for many different reasons. Perhaps the reason you run is to get rid of stress, run with your dogs, to stay healthy, to compete in races or to lose weight. But people don’t generally choose running as a way to build muscle. So what are you to do if you want to run more and start training for a marathon, but also want to maintain or build muscle at the same time?

It is difficult to build muscle while training for a marathon because long-distance running (which you’ll be doing a lot of) has the ability to hinder muscle growth. On the other hand, incorporating high-intensity exercises, strength work, and sprint running into your training will help you maintain your current muscle mass.

Here we’ll cover if you can train for a marathon and build muscle at the same time and what you can do to ensure you don’t lose the muscle you already have, including how to eat properly to do so.

Building Muscle vs. Maintaining Muscle While Marathon Training

It’s important to first point out that building muscle and maintaining it are two very different things. If building muscle is truly what you’re after, doing so while simultaneously marathon training is pretty tough. However, as long as you keep up with strength-building exercises, there’s no reason why you can’t maintain and keep the muscle that you already have going into marathon training.

Why is building muscle so hard while training for a marathon?

Long-distance running can hinder muscle growth, and obviously, a marathon is the ultimate example of distance running (before moving onto ultramarathons, at least.)

How do we know this? A study of 30 male amateur runners who ran 6.2, 13, or 26.2 miles showed that they all experienced significant signs of muscle damage after racing at these distances. As the running distances got longer, so did the muscle damage.

“Muscle damage” sounds a bit scary, don’t you think? I mean, who would want to purposely do this to themselves? But even though “damage” sounds bad, we also have to remember that these were races, not training runs – most of which should be done at an easier pace. But even a long run at easy pace can cause muscle damage (and I guarantee you’ll be able to feel it!)

This muscle damage doesn’t mean that dangerous is by any means, and if you don’t believe me, read, “The Dangers of Marathon Running and How to Avoid Them.” What it does mean is that your body needs time to recuperate, which can be done through rest and recovery running. It also means that distance running is not building up your muscles like lifting weights or strength training does. It does the opposite. So, lots of running = not the go to for muscle growing (if that’s what you’re after). (Short bouts of high intensity running, is different, however, which we’ll cover later.)

But is it possible to MAINTAIN muscle while marathon training?

Maintaining muscle means keeping what you already have there when you begin your marathon training. And absolutely, if you are training correctly and eating properly, there is no reason why you would lose muscle by running lots of miles or running long distances.

Running can build your lower body, but it depends on the intensity and duration of your runs. Hight intensity running is the best for building and keeping muscle.

However, most people don’t do HIIT exercises when training for a marathon. Instead, they do long-distance runs.

The results of these researchers found that high intensity, short duration running builds leg muscles, while long-distance running causes significant muscle damage, which then hinders your muscle growth.

How to Train for a Marathon Without Losing Muscle

Building muscle during marathon training is extremely tough to do if you’re really focused on training well and reaching your potential. But there is no reason why you can’t train well and maintain your muscle and strength. Doing the following will ensure you train well and keep your body strong.

Go Into Marathon Training Already Strong

The most important thing when it comes to training for a marathon without losing muscle is to build some muscle prior to it. Strength training can actually help you when running, because it engages your core more, makes your arms stronger, and lowers the risk of injury.

When you’ve built some muscle, you will be stronger, less likely to get injured, and you will probably be faster and able to eat more.

Eat the Right Foods to Maintain Muscle

When you’re training for a marathon and you don’t want to lose muscle, you will have to focus on your nutrition.

Eat Carbohydrates: Eating carbs before and after every run is crucial for filling and refilling glycogen stores. For one, you need this to have the energy necessary for all the calories you’ll burn as you run. And in terms of maintaining your muscle, if you don’t consume carbohydrates to fill glycogen stores after they’ve been emptied out, your body will look for food elsewhere. They first place it will look is muscle. But don’t fear. It is a MYTH that running eats away your muscles, generally speaking. If you are eating properly, this won’t happen. Plan to eat a proper diet, and eat to fill your hunger, and your muscles will stay there – nice and strong!

And don’t forget to eat carbs on your long runs, too. During this time you’ll burn a lot of calories that you need to fill up. You should eat about 50g of carb per hour of running on your long runs. I discuss this extensively in, “Long Run Nutrition: Foods to Eat During Your Marathon.”

RELATED: “The Carbo-Load: Why do marathon runners do this?

Eat Protein: Additionally, consuming proper amounts of protein daily is key to maintaining your muscle. According to this study published in PubMed Central, protein is important for endurance athletes to consume. They write, “Attention to adequate intake is emphasized to improve recovery, ameliorate muscle damage, and maintain muscle mass.”

Supplement as needed: Lastly, Branch Chains Amino Acids (BCAAs) can be helpful and many runners rely on them for recovery. BCAAs are 3 essential amino acids that help support protein synthesis and those are leucine, isoleucine, and valine. However, there is not a ton of evidence to show they are necessary, and this article cites a study where leucine alone is actually more beneficial. You can find a highly recommended leucine powder here.

Find out how even chocolate milk can keep your muscle maintenance on track!

More important than taking supplements however, and perhaps even eating the right “mix” of foods, is simply taking enough calories. Though it is a myth that endurance running causes the body to “eat” muscle, this can and will happen if someone is malnourished and not taking in enough calories to meet the demands of long-distance running.

When runners don’t eat enough, both muscle and fat loss will occur. When you’re running for a longer period of time without enough fuel, your body will start to use your muscle to power your run. That’s why you will have to be very aware of how much carbs and protein you’re eating.

Incorporate Hight Intensity Workouts and Weight Training

One major reason that building muscle is so tough during marathon training is the factor of TIME. Most people just don’t have enough time to train well for a marathon AND do what it takes to build up muscle at the same time. Both require a lot of focused effort and hours of work each and every week. With most people’s schedules it’s just not possible to safely and effectively do both.

However, good marathon training should incorporate strength-building type exercises. This can be done through HIIT workouts.

Another good way to build and maintain muscle while training for a marathon is to incorporate weightlifting exercises on the days when you’re not doing long runs. This will not only help you build muscle but also make you stronger and faster. You will want to do core, glute, and upper body exercises. It is very important to eat enough to fuel your body for training because if you don’t, it will start to eat your muscles.

Make sure you’re not doing strength training without a purpose. You should do exercises that make sense for running. Focus on workouts that will make you a better runner, such as glute, core, and upper body workouts.

Run Fast and Run Uphill to Maintain Muscle

Though long, easy runs don’t contribute to increasing muscle mass, there are type of running that can effectively build muscle.

You can build lower body muscles with high intensity, short duration running workouts. This is especially true for your quadriceps and hamstrings.

One study researched 12 recreationally-trained college students who did HIIT exercises involving 4 sets of running at or near maximum capacity for 4 minutes, followed by 3 minutes of active rest. After 10 weeks their muscle fiber area of their quadriceps increased to about 11% compared to a control group.

Take a look at a professional marathon runner vs. a sprinter. Their bodies look VERY different. That’s because sprinting builds muscle, and sprinting fast requires very strong leg muscles.

Images by:
Fernando Frazão/Agência Brasil
and Rich Kenington ~ Photos on the Run – Wikimedia Commons

The world’s fastest marathoner, Eliud Kipchoge, is less muscular than the world’s fastest sprinter, Usain Bolt.

The best running workouts to build strength involve sprints and hills sprints. Though it would be advisable that you do these 3 to 4 times a week if you were wanting to build muscle as part of a strength training program, it is NOT safe to do this during marathon training.

Instead, plan to do either a speed workout OR uphill speed workout once per week in marathon training. Incorporating a hilly route during runs throughout the week will help, too.

Sprinting/Speed Work

Sprinting isn’t generally the primary method for muscle growth, but it will help you get bigger in a short amount of time. It has been associated with athletic development rather than as a way to build quality muscle mass.

Sprinting is a form of speed training, and speed training prevents fat gain. According to T-Nation, “it creates a huge metabolic disturbance and is one of the best methods for losing or maintaining fat stores.” Once you start sprinting, body fat stores rapidly decrease, and muscle size increases. The reason why is because post-exercise oxygen consumption sucks up calories like a sponge for hours after high-intensity training.

Sprinting will improve your anaerobic conditioning levels (whereas marathon running is 97.5% aerobic conversely.) And working more in this type of hypertrophy training zone will allow for muscle engagement throughout the entire body, as the body is pushed to anaerobic limits. Sprinting will generate greater rep work output, which will result in more muscle growth.

To incorporate these sprint workouts safely while marathon training, I highly suggest doing it under the guidance of a coach. If you plan to do these on your own, you should not be doing them more than once per week to prevent injury.

RELATED: How to Prevent Injury in Marathon Training

DO STRIDES! Strides are essentially reps of short sprints (20-30 seconds) done at the end of an easy run that are great for maintaining muscle and should be incorporated in a quality marathon training program. Here’s the nitty gritty from Runner’s World.

Sprinting immediately after your warm-up but before strength training will make your CNS and force output far greater which will result in more muscle growth.

Sprinting is also a form of progressive overload. Barbells, kettlebells, and dumbbells are all external resistance while sprinting offers a form of resistance by way of the momentum of our body mass, which creates another essential source of overload.

Studies show that landing impact during sprinting sometimes even exceeds three times your bodyweight.

Sprinting is a good way to train your hamstrings because the hamstrings are the dominant muscle group in sprinting.

Uphill Running

Uphill sprints are another great way to build muscle while running. They are a form of resistive training or sprint loading. Racing uphill forces you to work against the weight of gravity. Most runners have heard the phrase, “Running hills is speed work in disguise.”

Uphill sprints are a form of resistance training, which means that they will break down the muscles in your legs and glutes, causing small tears in your muscle tissue. When your body tries to repair these tears, it will build muscle mass. Sprinting on an incline means that you will need greater knee thrust with your front leg as well as push-off with your back leg to lift your body weight – building up those quads and calves.

It’s important to be careful not to do uphill sprints for too long or do too many. Keep them short and fast – about 8-12 seconds in length at a 6-10% incline. Running them longer/at a higher incline isn’t necessary, and it will lead to fatigue and increase the risk of injury.

Since uphill sprinting is a form of resistance training, implementing a recovery run the following day is crucial.

How often should you lift weights while training for a marathon?

Even though your highest priority when training for a marathon is running, lifting weights is also beneficial. You should do weight training on days when you’re not doing speed work or long runs because those types of running are hard on your body, and adding weight training to that will increase your risk of overstressing the body and decreasing your conditioning. Instead, do your weight training on a day off or on a day where you have a shorter, easy run.

You should always have a day of rest between weightlifting sessions. You should also have at least one rest day a week when you rest from all types of workouts.

Preserving lean muscle doesn’t call for the same lifting intensity as building bulk. It should be enough for you to hit each muscle group twice per week, or at minimum once per week. You can see how this is doable while doing a proper marathon training program, whereas doing enough weight training to build muscle at the same time would be very hard.

When you’re training for a marathon, you should keep your training volume low and do compound exercises – exercises that work multiple muscle groups at the same time (here are some great examples.) Limiting yourself to two-three sets of compound exercises per workout will allow you to fit in a complete range of exercises while lowering the chances that you overdo any of them.

Bodyweight exercises are great for maintaining muscle, too. Box jumps, jumping lunges, push-ups, burpees, and sit-ups are all great for strength maintenance to supplement your running.

Last Word on Building Muscle Combined with Marathon Training

It will be extremely tough for you to get a more muscular physique while marathon training. However, endurance running often leads to fat loss, which will make your muscles more obvious if you do the steps above to maintain your muscle mass. I’ve found this to be true for myself every time I train for a marathon.

And honestly, these are just two separate goals to have for yourself, in my opinion. If you want to do both, have periods of time where you strictly focus on strength-building and then parlay that into a great marathon training cycle. Then you can go back to more strength-building. You can have both, just probably not at the same time.

If you do truly want to do both at the same time, I’m not going to tell you it’s impossible. I would encourage you to find a coach who is highly skilled in incorporating a vigorous strength training program safely into marathon training and find out what they have to say.

Jane

Hi, I'm Jane! I'm an avid runner who races 5ks to marathons. After a 4:59 first marathon, I came back to the distance years later running a BQ time of 3:36. I did a lot wrong for a long time and finally started doing a lot right. Now I'm an RRCA certified running coach and love sharing what I've learned to help others run their best.

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