Special Workout :: Yasso 800 - The Marathon Pace Workout with a Twist

Named after Runner's World editor Bart Yasso, this workout, the Yasso 800, has gained quite a bit of popularity over the last few years.

It is a marathon pace workout with a twist.

On this page I am exploring the merits of this special workout.

I'll cover off on the following topics:

So, how do you do this marathon pace workout?

Are Yasso 800s helpful in predicting your marathon pace?

Is there value in the Yasso 800 as a marathon pace indicator?

Using the Yasso 800 as a half marathon pace guide.

Are Yasso 800s a good workout?

So, How Do You Do This Marathon Pace Workout?

The Yasso 800 is called that way because it revolves around 800 metre repeats. Your goal is to run these 800 metre-repeats at a constant pace.

The time you spend running these 800 metres in minutes, is a prediction of how fast you can run your marathon in hours.

I told you it was a marathon pace workout with a twist! It is not run on marathon pace. But if you are able to do 10-12 800 metre repeats at a certain pace, the theory is that you can predict your marathon time based on it.

Let's have a look at an example to make it come alive. Say you do your Yasso 800s at 3:30 min / 800 metres. In between you do a recovery jog for the same amount of time (so 3:30 min).

Are you able to do that 10-12x in a row? Then you should be able to run a 3:30hr marathon.

Doing your 800 metre-repeats at 2:50 min / 800 metres (recovery jog for 2:50 min)? Then your predicted marathon time is 2 hours and 50 minutes.

Almost too good to be true... And yes, it often is.I will explain why.

It is still a good workout though, so don't take the below as a criticism on the workout or its creator! I have found that instead of using it for the marathon, it has got a really good use for the half marathon. Anyways, below I will get into all of that... So, let's move on!

Are Yasso 800s Helpful in Predicting Your Marathon Pace?

So, are Yasso 800s helpful?

Think about it. 800 metres compared to 26.2 miles. A marathon is about 53 times more than 800 metres.

That's a massive difference.

Half marathons are, I think, a better predictor for marathon performance. Provided you do the work required for your marathon. Just use my marathon calculator page to find out more and Bob is your uncle!

However, the difference between 800m and 26.2 miles is huge. The marathon requires a sufficiently developed aerobic base.

Running 800 metre repeats at a faster clip is not going to be a great comparison for it. Doesn't mean it is not a good workout. Running 12 x 800m already gets you to 6 miles, add in 12 x recovery jogging, a warm-up and a cool-down you get a very decent middle-distance long run with faster running thrown in.

However, as a predictor, I think you will find that the Yasso 800 is often somewhat too positive about your marathon goal time.

There is simply a lot more involved in running a three hour marathon than being able to run 10-12x 800 metre-repeats in three minutes. It's nice. It's gimmicky. But unfortunately it's not that simple.

Is There Value in the Yasso 800 as a Pace Indicator?

In several forum discussions I have seen runners claiming that the Yasso 800s do predict your marathon time if during all 800 metre repeats your heart rate stays at the same level.

If it creeps up during the workout you will probably not be able to run your race at the predicted time.

I have not tried this out myself, but tend to believe it.

When your heart rate does not move during a workout which has you running at about tempo pace or above it, then you have little difficulty with that pace.

Still, when I want to establish my predicted race pace I like to use more than just the Yasso 800.

I prefer:

Recent half marathon race times

Then combine that with knowledge I have of my current long run, tempo run and interval paces.

Importantly, do some marathon goal pace sessions and see how they go. Long runs with marathon pace blocks are really big predictors and great training!

So take all of that info.

Then cross-reference it with Yasso 800 info.

That together provides me with the info on how fast I can be in my next marathon.

But relying on the Yasso 800 alone is, in my opinion, not sufficient.

Also see my tips for running a marathon page to learn everything necessary about marathon pace training and marathon pace strategy.

Using the Yasso 800 as a Half Marathon Pace Guide

A better possibility I see is to use this workout as a half marathon pace indicator. Whereas the marathon is an unpredictable beast, the half marathon is more predictable. After all, it's often a bit unclear for all of us how we'll go in those last six miles / 10k of the marathon, whereas with proper training and pacing you can almost be guaranteed you can finish a half marathon strongly.

So, how do you use the Yasso 800 as a half marathon pace indicator?

Be warned... the next bit is reliant on some maths and a number of process steps... So, it is not the easiest. But I'll lay it out step by step. And will then provide a few examples for you to work through as well... Just know, that I have used this in the past and found it to be helpful, both for me and my clients. So, it is worth trying to persevere through this...:

In the run-up to your half marathon you have been doing some Yasso 800s and have found you can run 12 x 800m at 3:30min.

Theoretically, this corresponds to a 3hr30 marathon. Now, find the equivalent half marathon time using this race conversion calculator. Fill in 3hr30 for a marathon and then predict the half marathon time.

If you have done it correctly, it predicts a half marathon of just below 1:41. So, if you can run Yasso 800s at 3:30min, then this predicts a half marathon of a little less than ~1:41.

Let's do another example.

Example 1
E.g. Suppose you have recently run a 10k in 43 minutes. Using the race conversion calculator in the link above, you'll work out that your predicted half marathon time would be about 1:35 and your predicted marathon time would be about 3:18.

Now, when you can do a Yasso 800 workout of 10-12 x 800 metres in 3 min 18 per 800 metre repeat with 3 min 18 sec jogging in between, you'll have another good indication that you can indeed hit that 1:35 half marathon time.

Makes sense?

Or are we getting too complicated here?

Let's walk through another example.


Example 2
Suppose you have recently done a 5k race in 25 minutes. Then, with use of the race conversion calculator you will find a predicted half marathon time of 1 hr 55 mins and a predicted full marathon time of just under 4 hrs.

So, if you can do a Yasso 800 workout of 10-12 x 800 metre repeats at 4 mins per repeat (4 min jog in between), then that will help give you some good guidance that 1:55 is indeed feasible.




Of course, there are other half marathon goal pace sessions you can do, the link will give you some good examples.

When deciding on your race pace, no matter if it is a half marathon, full marathon or any other distance, it is generally best to use a number of different references.

Use a recent race. Use some recent training paces. And use the Yasso 800 workout together. The big mistake you can make is relying on intuition or just one indicator. That one indicator may be overly positive and that can set you up for failure.

I know some folks who are incredibly good at short distance runs like the 800m. They'd be able to run 3min 800s the whole afternoon, but they'd really struggle hitting a 3hr marathon as they haven't done sufficient long runs.

Are Yasso 800s a Good Workout?

Yes, as I have said before, Yassos are a good workout. There is nothing wrong with doing 800 metre-repeats.

And doing it 10-12x in a row and moderately hard pace is a very decent workout indeed.

You cover a decent amount of mileage and you are doing it at quality pace.

So, pretty good.

However, in terms of optimal marathon preparations, it is one in a whole arsenal of good workouts. With some of them distinctly better. Long runs, marathon pace and tempo runs.

So, 800 metre repeats are good, but for a marathon, I would not sacrifice a massive amount of your marathon training schedule for Yasso 800s.

Vary with distance and speeds to get more variety in your training and ultimately, end up better prepared for your marathon race. I would recommend to do Yasso 800s once or twice in a marathon cycle. But not much more.

I hope this provides you with sufficient information about the Yasso 800 to make up your own mind about it.

It is an interesting workout and has definitely become popular because of its suggested predictiveness. But, as I hope I have explained before, I would not rely on the Yasso 800 alone to work out your appropriate marathon pace. It will not give you all the information you need. And you might end up disappointed in your race.

But it has some merit. And as half marathon pace indicator it can certainly be helpful.

All in all, do them a couple of times in a marathon cycle and use them as a useful workout first, and as somewhat of a predictor, second!

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