Easy runs form the foundation of an ultra-runner’s training. Around 80-90% of training time should be spent at a relaxed, aerobic pace, allowing the body to build endurance without negatively affected the harder and long runs in the training week.
Yet they are often run too fast , and most people don’t fully understand the benefits of them.
Are they easy runs or recovery runs?
If recovery was the primary goal, then we would be better off doing a non-impact activity like cycling or swimming rather than another run. Non impact cross training increases blood flow to the muscles without adding any extra stress on already tired muscles. The easy runs that make up a large percentage of our training are not recovery runs.
Think of it another way – if you are doing some strength work and you do a hard chest work out eg some heavy bench press or similar. The next day do you would you do some pushups to help recovery ? Or would a swim be a better recovery option? Anyone who has had sore pecs from a heavy bench will tell you a swim would be a far better option than trying to do some push ups ! Push ups are same action as bench press just a lighter load ( assuming you can bench heavy ! ) so you are just fatiguing fatigued muscles even more.
Yet in running we think that easy runs are helping us recover from harder runs. They arent. Running is running, and all running be it easy or hard adds to the training load on our legs.
But easy runs run the lactate out of our legs I hear some of you say – we will discuss in detail about this in the video on lactate but in short the lactate from your hard run yesterday was gone before you went to bed.
So why run easy if it’s not for recovery ?
The purpose of the easy runs include
– building aerobic base
– improving running economy
– increase musculo-skeletal endurance
– Increase myoglobin content of muscle fibers
– developing mental strategies when running at a slow pace
– increase mitochondria density
– increased mitochondria function
– increased capillary density
– increased recruitment of slow twitch fibres
Think of all the different intensity runs one can do , each of them results in a different level training stress on the body. The goal of any training program is to train at the highest training load the body can adapt to. Too much stress and the body starts breaking down , too little stress and you arent improving as much as you could.
The key to maximising the amount of training load one can adapt to is balancing the intensity of training. Harder and longer runs require more recovery whereas shorter easy runs require less.
If we compare two different training weeks
Week 1
Two very hard threshold or above threshold sessions and a long run
Week 2
Two hard threshold sessions ( but easier than the ones in week 1 )
Four easy runs
One long run
If we look at the overall training load visually it may look like this
Week 1
Where the red dots equal the harder sessions and the blue dot the long run and the size of the rectangle reflects the training stress placed on the body.
This load may be the maximum the athlete can tolerate
Week 2
Green dots represent easy runs
Orange dots are the harder sessions ( but easier then the red dot sessions in week 1 )
Blue is long run
Now if we compare the training load of each side by side
We can see the athlete is capable of a greater training load with the easy runs and slightly easier harder runs of week 2 than of week 1.
The easy runs main purpose is not for recovery, it’s to increase the training load safely to maximise adaptions.
Those astute viewers may be wondering, surely if we are measuring training stress score then the athlete should be able to handle the same numbers no matter how it’s made up ? Ie if an athlete can handle a TSS of 500 it shouldn’t matter if that 500 comes from 2 runs of 150 and a run of 300 or 5 runs of 100.
I’ll go into this in detail in the training metrics video but the summary is TSS is a useful metric but has its limitations.
For example an athlete of mine did a 100km race with a TSS of 540 . Leading up to that he had a period of 8 weeks with TSS over 540 every week yet after the race needed 2 weeks recovery. Ie not all training stress is equal . I’ll explain more in the video.
The key take home is that not all training stress is the same. Increasing the easy running volume in our training plan allows to increase the amount of training stress we can handle and therefore improve performance.
How easy is easy ?
The two ways I prescribe easy runs to my athletes are
– full conversation pace – ie if you were talking on the phone the other person might hear the wind but would barely be able to tell you are running
– \< 80% of Threshold
Can you run too easy ?
Yes you can but only when you get to a speed that feels unnaturally slow. Even then there is likely still benefit as it probably matches the pace you are running in the back end of a long ultra !
Is there a specific pace I should target for easy runs or will it vary ?
It will vary from day to day – some days easy will feel more like 80% of Threshold other days 75% and some days 70% – thats 100% ok and you should never try to force the pace to keep up with a predetermined pace target.
Can I run a bit faster than 80% if I am feeling good and it still feels easy?
Generally speaking no . However if your training volume is low, you’re not doing any hard sessions, and you’re injury-free, adding a few Zone 3 runs can be helpful (see the Zone 2 vs Zone 3 video). But if you’re increasing your volume, already training at a high volume for you, doing higher-intensity sessions, or finding long runs tiring, you’re much better off keeping easy runs in Zone 2.”
The other time speeding up is ok is when your initial pace is slower than usual.
For example if I run first thing in the morning straight out of bed and out the door then my first k might be 6:15 min ks or even slower ( ie more like 70% of threshold ) but by the end of an hours run its up to 5:30 pace ( around 80% of threshold ) , whereas if I run mid morning the first k might be 5:45 but I will still only get to 5:30ish pace . Its just that in the early morning run it took me a bit longer to warm up
Can I use pace to determine my easy runs ?
There are a ton of different recommendations on how easy your easy runs should be , often referencing ones pace in a 5km or 10k or marathon.
here is a selection of recommendations found on google fro what most would consider reliable sources
Easy run pace
– 60 seconds slower than 5k pace
– 60-90 seconds slower than marathon pace
– 60 seconds slower than 10km pace
– 2 minutes slower than 5k pace
– 65% of 5k pace
– 50-75% of VO2 max
Clearly there is a wide range of paces suggested there
For example if we take a 25 minute 5k runner
that equates to approximately 52mins 10k and a 4 hour Marathon and using the examples above easy runs would be anywhere from
6 min ks to 7:41 min ks. Many would find 7:40 min ks too slow and feel unnatural running at that pace and 6 min ks is likely too fast
The idea that we can pin a recommendation to a race distance doesnt make sense to me. Some people’s 10km pace will be 30 minutes others 60 minutes , should they all run 60 seconds slower than 10km pace?
I prefer to either use the talk test or cap it at 80% of threshold (and anything slower than that is fine ) so people get away from trying to run a certain pace.
What terrain should my easy runs be on ?
I suggest that even if training for a very hilly mountain race that the terrain for an easy run should be almost all runnable. Doesn’t have to be flat but should not be so hilly that you need to hike much of it. The rationale for this is that a) these are not recovery runs , they are building aerobic base and b) when training for mountain ultras we usually get plenty of hiking in the long runs , the easy run is a good time to work on your running fitness.
But if you can’t run up a hill keeping the intensity down, then I suggest you hike instead. The reason for this is that the short durations of pushing harder in easy runs increase mechanical and cardiovascular loading, increasing fatigue, which can impact the harder runs later in the week.
How long should my easy runs be?
For most runners, an easy run typically lasts between 45 to 75 minutes. Beyond that, the training stress starts to rise, potentially impacting recovery and the ability to perform well in harder sessions later in the week. Keeping easy runs to less than approx 75 minutes helps maintain a balance between training load and recovery, ensuring that tougher workouts aren’t compromised.
Higher mileage athletes may be able to go up to 90 minutes or split the 90 minutes into two runs morning and evening.
Key Take Homes
Easy runs build volume and develop aerobic capacity without detracting from harder and longer training sessions.
Although a one-hour Zone 3 run may trigger more aerobic adaptations than a one-hour Zone 2 run, your body can handle far more Zone 2 training without compromising harder and longer sessions later in the week. That’s why easy runs should stay in Zone 2, not Zone 3.
The duration of the easy run needs to be short enough that the training stress does not negatively impact harder or longer runs.
Terrain for the easy run should be mainly runnable