Finishing a marathon forces the body to go through hell and come back. It can break people both physically and mentally. Some of us do it once as a bucket list goal, while others are crazy enough to carry on chasing Personal Bests and finishline endorphins. Either way, marathon long run is THE session that prepares runners for this madness.

I originally wrote this post as my personal running experience as I trained for my first marathon. In particular, ~8 weeks before to look back at my training to see if I’ve missed something. Since then, I’ve revisited my tips and updated this post numerous times with my experience – as an athlete and a coach.

In my first marathon, despite training consistency, I haven’t done many runs longer than 2 hours. In part because mostly throughout the training my weekly volume was only around 40K. That’s even less than what I did for a half marathon the year before.

I did focus on improving speed and the quality of my sessions, though, which did help a lot.

Marathon long run

So, what makes the long run so important?

Regular runs of over 1 hour gradually prepare the body for the demands of a marathon. The benefits of this kind of training are:

  • Improved endurance and running economy
  • Stronger muscles and connective tissues
  • More efficient fat-burning process
  • Mental toughness
mental preparation for the maratho long run
Marathon long run helps to train mental toughness and over time gives the courage that you can actually do it.

Marathon long run is indeed a very versatile workout. But sometimes athletes get it wrong:

MYTH: I need to complete a 20-miler (32k) during marathon training to be able to finish the race.

FACT: Running that long does help to simulate demands of a marathon and specialize better for the distance. But it’s not a ‘marathon requirement’. In fact, in my 3:03 marathon the longest I ran was 16k (I shared earlier how I trained for a 3-hour marathon on 30 minutes per day). Running very long will only work if the athlete is able to process that training load and recovery fully before the next key workout.

MYTH: Marathon long run is only about time on your feet. Athletes just need to get through it and not worry about pace or effort level.

FACT: Again, we need to think about the demands of a race. Most of the athletes will run the marathon somewhere between 2:30 and 5:30 hours. That’s a wide range of intensities (Zone 3 to Zone 4) and running easy all the time will not fully prepare the person for the race intensity (even if it’s a 20-miler).

There are quite a few variables in ‘running long’. For instance, how long or how hard? And should it be long and slow all the time or should there be some variety?

Duration – how long to run?

Due to high impact of running it’s not very healthy to run for over 2.5 hours. Running this long builds a lot of fatigue. If taken too far, it can throw off half of the next week’s training.

Contrary to the advice that is out there, it’s not a requirement to complete a 20-miler (33K) in the build up for a marathon. It does sound like a rite of passage, though.

For the average runner the time needed to cover that distance will not outweigh the benefits. With a pace of 6:00min/km one will need almost 3.5 hours for this session. It’s better to go for a hike or do a double day instead.

Generally, long runs of 1:40 to 2:20 hours are perfect for most athletes. But do make sure it’s under 20-30% of your weekly total mileage.

It’s enough time to stimulate adaptations and not too long to build too much fatigue. Also, it’s best to mix up the duration of the run from week to week to manage intensity and recovery. For instance, a 2:20 hour easier run one weekend and a 1:40 hour more intense run the next.

Running this long requires gradual adaptation, though (around 10%-15% increase per week). Too much volume too soon can lead to overused muscles, accumulated fatigue and can, actually, reverse the gains.

Effort – how hard to run?

Not hard at all.

There is this saying, if you think you’re running easy, you’re running too hard, which is totally true. The intensity of a ‘classic’ long run should be no higher than Zones 1 and 2. Many athletes tend to over-estimate that.

In the end it’s a two-way street. What low intensity and long duration do is provide the best combination to grow mitochondria in the muscles and train the effective fat utilization.

Related: 5 Heart Rate Training Zones – Guide To Maximum Endurance Gains

Ability to utilize fat is critical for marathon runners, as there is only limited amount of glycogen (carbs) stored in our muscles. Once this reserve starts to run out, the athlete comes to a very frustrating stop and ‘hits the wall’.

With training, though, athlete becomes less reliant on carbs and the speed he is able to maintain at low intensity will also increase.

Nutrition – how to fuel for a long run?

The most important thing about nutrition is to get enough water to avoid dehydration. If it’s a particularly hot day it’s a good idea to add electrolyte tablets as well to get enough sodium. I prefer to take it in a throwaway bottle and have some cash to buy more if needed.

Apart from that it’s really about testing out what works for the body and what’s not. After all, every athlete is different and what works for one runner may not work for another.

Marathon long run is the best time to test out different fueling strategies and find what works for you.

Generally, though, if the training lasts for longer than 1.5 hours and involves intensity (like high Zone 2 or higher) it’s better to take additional fuel with you.

Liquid calories, like gels, work best, because those are easier to consume and digest.

Marathon long run variations

After an athlete can comfortably complete a 1.5 to 2 hour run at an easy pace it’s time to add some variety to the long run to better prepare for race day.

In particular, adding efforts at marathon pace and slightly above it (upper Zone 3 for most athletes) will train the body to maintain the pace better on race day.

Marathon long run variations
Adding more intensity to the long run will also help to break the monotony of it.

#1 Progression run

The idea behind a progression run is to finish the session faster than you’ve started it. Adding intensity at the end of the long run simulates the last quarter of the marathon when the body is tired, but there are still 10K to go. So, this session teaches the body to run at (or above) marathon pace on tired legs.

How? Aim to gradually increase the effort in the last third of the run by ~10sec/km every kilometer – so, 5:30min/km, 5:20, 5:10, etc. – until the marathon pace.

With time you can start progression in the middle of the run and spend more time at marathon pace at the end.

#2 Under-fueled long run

Training in carb-depleted state improves the body’s ability to metabolize fats for fuel. Intensity of this kind of training should be very low (low Zone 2), so don’t pair it with any one of the other long run variations.

How? This should be one of the shortest long runs (1:30 hours, maybe) and it’s better to do it first thing in the morning. Go veeery easy and take water with you.

#3 Marathon pace practice

This is a great session to practice pacing and feel what the body is capable of. The goal is to include a portion at marathon pace (target heart rate Zone 3 for majority of runners) in the middle of the long run.

How? Start with ~20 minutes at marathon pace and over time gradually build up the marathon pace portion to around 60% of the total duration. So, a 2 hour long run may look as following – 30 minutes easy, 1:10 hours at marathon pace, 20 minutes easy.

#4 Broken tempo long run

Tempo effort is slightly faster (10-15sec per km or high Zone 3) than a marathon pace. Adding it to a long run trains the body to tolerate that effort better. As a result, marathon effort on race day will seem easier.

These broken tempo intervals are not too long (typically 10-20 minutes) and are followed by a long rest period (10-15 minutes). This way you get plenty of recovery, but still accumulate a good training load.

How? Perform 2-4 tempo efforts of 10-20 minutes with 10-15 minutes easy running in between. Aim for no more than 40% of the total run at tempo effort to avoid building too much fatigue. A ~2 hour session can look as following: 20 minutes easy, then 3×15 minutes tempo effort with 15 minutes easy in between and finish off with 20 minutes easy.

#5 Fartlek long run

Fartlek (or Speed Play) is an effective way to add variety to your marathon long run. Use effort/pace variations every now and then throughout your long session to mix it up. The goal is to trigger some fatigue and then let the body process it. This helps your legs to get used to running at a quicker pace for longer duration. The best part about this is that this session can be both – structured and unstructured. So, don’t stress too much about it.

How? Play around with intensity during your marathon long run session. For example, run easy for 10 minutes and then 1 minute at Zone 4 intensity and repeat the cycle throughout the session. Or throw in a an occasional 1k (or a mile) at marathon pace and come back to Zone 2 to recover for 5-10 minutes.

#6 Double days

Doing double days instead of one long session is a good starting point for beginners who don’t have enough running background. This type of long run training is frequently used by Ironman athletes who already accumulate a lot of stress from extensive bike training and want to minimize the risk of injury.

How? Exactly as it sounds – 2 training sessions per day. Split the long run into medium morning and evening sessions. This way you will even be able to add some intensity in the morning and run easy in the afternoon feeling the effect of fatigued legs.

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My first marathon training update

Update: I ran my first marathon and it was a roller coaster of emotions. Read my race report here, if you’re interested.

I am getting closer to the race day and am adding more intensity to my long runs.

This week I skipped cycling and focused on running and kayaking for a change. My weekly volume is around 60K now which I plan to sustain for the remaining 2 months.

I also plan to change the schedule of my long runs a bit and make it more structured. I’ll rotate a 2:20 hour long and easy run with 1:40 hour more intense run every two weeks. This should give enough volume to maintain endurance I’ve build and minimize fatigue from intensity I’m adding.

Currently I average around 20-25K during my marathon long run, but I want to do more to understand how to pace the race. Also, I’m really curious how my body will respond to even more running.

On a bitter note, I still haven’t nailed the stretching routine. After my failed yoga party a month ago I’m trying to stretch muscles after every session, yet I’m still feeling tightness. I hope it will go away after the taper and just in time for the race.

marathon long run variations pin