Note: I copied and pasted this from my blog, and some of the links do not work but I am too lazy to check and change them all, so if you can't get to linked material from this post, refer to the original post here.
I've seen so many benefits from slowing down my easy runs that I want to tell the world so every runner can get these benefits. Learn from my mistakes, everyone! In the future I'll post more details about my personal experience, but in short, when I slowed down my easy runs I felt much stronger, had markedly fewer injuries/niggles, had reduced incidences of illness, experienced performance improvements (PRs in every distance from 5k to marathon at age 38-39), and began enjoying running even more, which I didn't even think was possible! I think why many runners don't do it is because running faster can produce short-term gains, and we see those gains and think that it works - I have been guilty of thinking exactly that! Plus it is fun to run fast and to say a certain "impressive" pace is easy.
The Two Simple Reasons Your Easy Days are Ruining Your Training
My favorite piece from this article is: "You cannot run too slowly on a recovery day, only too fast. Make sure you understand that. It is a simple concept that is notoriously hard to grasp."
The author notes, "In high school, I would often race my easy days around 6:45 mile pace and run my workout days around 6:30 pace. Ten years later, as a professional runner, I run many of my hard workouts at 5-minute mile pace or faster and my easy days at 8:30 pace or slower." I have read in several places that a big difference between amateur and professional runners is that amateurs have a much smaller pace differential between easy pace and workouts, wheres professionals have a huge pace differential. If you are running tempos at 7:30 pace and easy runs at 8:00 pace, you are either under-performing in workouts or over-reaching on easy days, and I would bet it is the latter!
The author also mentioned that going easy by "feel" is best for most runners, and while I agree with this after a person has learned to run easy, I see that a lot of runners don't know what it's like to actually run easy - they think they are doing it when they are running a moderate pace (I have been one of those people)! "Easy" and "not hard" are not the same.
Running slow is very common with Kenyan-born runners, and no one can argue what distance running powerhouses they are. The article notes, "Sally Kipyego, an Olympic silver medalist in the 10,000 meters, can hold a sub-5:00 minute pace in the event. Achieving that requires Kipyego to log plenty of hard track sessions and tempo runs. Yet on her non-workout days, she ambles along at 8:30-per-mile pace, sometimes even slower." Her easy pace is over 3:30 slower than her 10K pace, and clearly it works. Sally recently placed 3rd in the 2020 Olympic Trials. Side note: It completely blows my mind that a woman can average 4:55 pace for 6.2 miles!
I've read this time and time again, and you will see it as a recurring theme in this summary: “The common denominator among most really successful runners, people running at a high level, is a really wide chasm between training-run pace and where they work out....Brenda Martinez, who has PRs of 1:57.91 for 800m and 4:00.94 for 1500m, is a perfect example of this. Under the guidance of coach Joe Vigil, she’ll run 8 x 1,000m repeats at 2:55 [that is 4:41/mile pace!], but on her easy days, she’ll run a 9-minute pace."
The article also advises "runners to use 10K race pace plus 2 minutes for easy-day pace, wear heart rate monitors (and aim for 65 to 70 percent of maximum heart rate), or take occasional treadmill runs to monitor pace." While I am not at all a fan of treadmill running, it's clear there are benefits to setting it at a certain pace, whether easy or on a workout day, and letting it keep you there! This article presents the other side of the coin too (faster easy days and when they might be appropriate).
How Fast Should Your Easy Runs Be?
This one provides great scientific explanations, and if you're interested in the science behind easy running make sure to read the whole article. Just like heart rate doesn't lie, science does not lie! It also breaks down a lot of common questions (e.g., "But if I feel good can I run faster?", "Don't I get more benefit from running faster?", "How slow is too slow?", etc.).
I have personally found that I will run a faster marathon off of almost all easy running than off of frequent workouts at a slightly lower mileage volume. This is probably because, "...nothing will consistently help you improve continuously like developing the aerobic system."
For the numerically minded (and really, what runner isn't), "Your optimal easy run pace for aerobic development is between 55 and 75% of your 5k pace, with the average pace being about 65 %.... Running faster than 75% of your 5k pace on your long run doesn’t provide a lot of additional physiological benefit....In fact, the research indicates that it would be just as advantageous to run slower as it would be to run faster...Even though 50-55 % of 5k pace will seem too easy, the research clearly demonstrates that it still provides near optimal physiological aerobic adaptation."
I acknowledge that the slow easy runs method may not be best for short-term success. If you are running one training block, you might be better off running faster every day. But if that describes you, I doubt you're inventing the time to read this post, plus most runners I know are in it for the long-haul!
In the past I've fallen victim to thinking that I had to run a lot of workouts to get faster, but I had a similar experience to this: “You think you have to do a lot of speed work to get faster,” he said, “but after doing most of my runs at a slow pace my marathon finish time was much faster.”
This article mentions how to calculate an appropriate easy pace based on heart rate, and also mentions the "talk test". I don't know how the talk test goes for others, but I can converse when running marathon pace but that is NOT an easy pace for me.
If your race performance has plateaued or you've dealt with reoccurring injuries, slowing down your easy runs might be just what you need to break through. It seems very counter-intuitive; we want to go pound workouts and pick up the pace every day to get faster, but "While some runners have success with faster paces on easy days (particularly lower volume runners), eventually even those runners usually see diminishing returns as aerobic adaptations from moderate running get tapped out."
"Polarization essentially means that training is usually easy or hard, rather than a grinding-it-out moderate all the time. Lots of “grey-area” moderate running can increase injury risk and lead to stagnation due to the absence of adequate recovery and faster stimuli." When I was training for a goal pace of 6:15 for the Indy Monumental Marathon, I noticed that I rarely ran between 6:15-7:45 pace - the "gray area" for me (if I was hitting 7:15-7:30 at the end of an easy run it was only because someone I was running with was speeding up). My workouts were at 5:30-6:15 pace, and my easy runs were 7:45-8:30 pace. It wouldn't have hurt me to run easy runs slower than that - many runners who are much faster than me do.
Seriously, run slow to run fast.
"...as 2018 Ironman World Championships runner-up Bart Aernouts said... “a slow run can only be too fast, not too slow” [notice a reoccurring theme here?]. Bart’s really easy runs are paced between 6:54/mile and 8:03/mile. That’s not super slow, but some of you are likely running most of your runs at a similar pace – and you’re likely not one of only two men to finish the iconic Kona Ironman course in under eight hours, running a 2:45:41 marathon, averaging 6:19/mile after a 2.4-mile swim, and a 112-mile ride in the Hawaiian heat. If that’s the case, it’s time to slow it down." I think that pretty much speaks for itself - a 2:45 marathon after swimming and biking for 5+ hours in terribly hot conditions in insane!
But what pace should we run? "For non-elite athletes, coach Luke Humphrey...recommends 1:30–2:30 minutes per mile slower than goal race pace." I'm not sure what race distance he is referring to, but less than 90 seconds per mile slower than any race pace is too fast to really be easy; well, unless you are one of those amazing people running 50 to 100 milers!
The article also mentions the importance of the other pieces of training programs, such as fast intervals. While this post is not about them, workouts are obviously essential to race success and should be included in a training schedule in addition to the awesome easy runs we are focused on here.
This article also discusses the difference between marathoners running sub-3:00 vs. 4-6 hours, which I thought was a helpful distinction. The faster you're racing, the more differential you should have between easy pace and marathon pace. A 2:59 marathoner needs to slow the pace down 1:30 or so per mile, while someone running a 4:30 marathon may only need to slow down by 0:45-1:15.
This is important for marathoners: "Part of doing those slower runs is that it teaches our bodies to burn fat, which is really important in a marathon because our carbohydrate stores only last so long," she says. "So the more efficient we are burning fat, the more we can push off hitting the wall." This is also a good point I hadn't thought about until now, but when I was running easy runs too fast I was more apt to hit the wall.
What Pace Should My Easy Runs Be?
We runners always want a number! "I recommend easy/recovery runs to be 90 seconds to 2 minutes per mile slower than your marathon pace."
Using the 80/20 Rule to Balance Triathlon Training Intensity
You Can't Run Too Slow on Your Long Runs!
I mean, the title says it all. He recommends marathon pace + 2:00.
In some ways it is harder to run slower for long runs, because it means significantly more time on feet! This article isn't focused on advanced marathon runners, but I think it's important to note that if you are trying to work your marathon time down, workout long runs become very important, especially later in the training cycle.