What should my long run pace be?

Yes! It absolutely does matter! 

Each run that you run has a very specific physiological purpose to help train and adapt your body in order to run the full 26.2 miles on marathon race day.

The specific purpose of the long run is to build those aerobic Type-1 muscle fibers that are absolutely essential in allowing your body to run the full 26.2 miles.

Without sufficient Type-1 muscle fibers you simply cannot run long distances. 

However, if you are trying to push your pace and run fast during these long runs you will not be allowing your body to build Type-1 muscle fibers and will ultimately be jeopardizing your potential to complete the marathon distance.

The goal of your shorter runs (and any interval, tempo, etc. workouts you might do) is to keep that muscle memory and train your body to run faster and be capable of running at your goal pace.

I like how Jeff Galloway puts it,

"You'll receive the endurance based upon the distance of the current long run. In other words a long run at 20 minutes per mile for 15 miles gives the same endurance as a 15 mile run at 10 minutes per mile or at 5 minutes per mile."

And that is exactly what we are after when running a long run: building endurance (not speed).

There are many reasons as to why your long run pace should be run slow and steady while training for a marathon or half marathon!

Here are 8 of the best reasons!

A lot of runners are running too fast and pushing their long run pace too much to take advantage of all the benefits that follow here.

They are constantly targeting either their anaerobic or both their aerobic and anaerobic systems.

As a long distance runner though we must focus on the aerobic system for the majority of our time spent training because that is where we are deriving the majority of our energy!

The more we target aerobic pathways the better we are able to utilize that energy and will have better success at endurance sports such as the half marathon or marathon.

The following is a chart from metrifit.com that stacks different sports and shows what percentage each sport requires from different energy pathways.

Long distance running: a whopping 70%!

Chart Source: metrifit.com 

Your capillaries are blood vessels that shuttle oxygen to the muscles. Essentially the more you have, the faster you can deliver oxygen and thereby produce energy to run longer.

Running at a slow and steady aerobic pace directly increases your capillary density which allows your body to utilize more oxygen and have more energy to run longer!

These fibers (as we have already previously mentioned) are aerobic in nature and allow you to run long endurance distances.

If you are training aerobically you will gain more of these muscle fibers that are essential to long distance running success.

If however you are always training fast and performing mainly speedwork and not slow running you will be building more Type II (anaerobic) muscle fibers that will compromise your ability to run long distances. You simply won't be building the right types of muscle fibers!

An increase in myoglobin means you will be able to release more oxygen when you are running at faster speeds.

Running at faster speeds requires more oxygen than what is being delivered to the muscle through the capillaries.

Here you can see how running slower long runs actually benefits you in your ability to become a faster long distance runner!

For example:

If you have a marathon goal race pace of 9 minutes per mile, you would want to run your long runs at about 9 minutes and 45 seconds per mile to up to 12 minutes per mile! 

This can be difficult for some runners to do as they feel as if they are barely moving or making progress during their long runs. 

But as we discussed previously, it is crucial to your success as a distance runner to run slower than your goal race pace.

As a marathoner, easy, slow paced long runs should be run basically all of the time.

You can probably already see how the benefits are essential to being a long distance runner. In order to run you need and want to be able to move oxygen rapidly, run longer distances, generate energy faster, be heart healthy, etc.

In fact, if you want to just be able to run faster while running long distances, you need to run your long runs slower.

Sounds like an oxymoron, doesn’t it.

But again, the benefits stated before will tell you why.

In short, you will be targeting the right energy system and simply put, that is what it is all about. If you skip out on these slower, easy training runs you will not be able to go the distance and reap the benefits that constant speed and hill training will not ever be able to give you.

Actually, yes!

If you are training for a marathon time goal and have a specific marathon goal pace that you are training and running at then you will need to focus on gaining strength and speed during your training and therefore your approach will be slightly different.

Let's talk a little bit about how your training and therefore long run pace will differ when training for a time goal.

When training for a marathon time goal speed workouts such as tempo runs and interval workouts are where you will train and gain the ability to nail your goal race paces!

I recommend running a tempo run about once a week if you are training for a time goal and to include an interval run once a week for the last 8-10 weeks of your training.

All this to say, there are definite benefits to training at your goal race pace during your long runs but typically this is for just a portion of your long run and not the entire run.

This is the case for goal pace and progressive style long runs which can also be found scheduled in the Break a Time Goal 16 Week Marathon Training Plans. 

In a nutshell, during goal pace long runs you will be practicing your goal pace during certain miles of your long run.

During progressive style long runs you will practice your goal pace during the final miles of your long run when your body is already fatigued and under pressure.

However, for the remaining miles, you will still want to run a slower-than-normal/slower-than-goal-pace long run pace which again would be about 45 seconds to up to 3 minutes slower than your goal race pace. 

Hopefully this post was able to shine some light on why you want to run a slow long run pace.

Be aware that by running at a long run pace that is too fast for you and your body will lead you to tax  that anaerobic energy pathway instead of doing what you want to be doing during your long runs which is building endurance and aerobic muscle fibers that are the only types of muscles that allow you to run long distances for long periods of time.

If your not used to all of the scientific methodology and periodization of training plans I can absolutely see how this might be confusing. Hopefully this has helped clear the air a bit on the subject. 

You still might prefer to do some more of your own research on the subject or sometimes it comes down to simply trusting in the physiological science behind a training plan and your body's response to it. 

How are you currently running your long runs?

Do you pace yourself at all, is your goal just to finish? have you been pushing the pace and perhaps need to slow down?

One thing is for sure...you can learn a lot about yourself and how you respond to training during your long runs and they are the best determinant for your marathon success! 

Sign up to receive the free printable strength exercises for runners: 👇

As featured on: