5k

A guide to post-race workouts for runners

Track season is nearly upon us and that’s got me thinking about a very track-centric question: when, if ever, should you do a workout after doing a race?

This strategy—a post-race workout—When used correctly, post-race workouts can help maintain an adequate training load and balance out the distribution of speeds within your training schedule, even when you’re racing frequently or have scheduling obligations to compete early in the season, when you’d like to be getting in more general and supportive training.

So, let’s take a look at what post race workouts are, who should use them, and when.

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New web app: a fast and simple race pace calculator for runners

screenshot of a race pace calculator for runners from running writings

I just launched a new web app: a simple and fast race-pace calculator!

🏃‍♀️ Try out my new race pace calculator here! 🏃‍♂️

After crunching pace-to-race and race-to-pace calculations by hand for about the millionth time, I decided I needed a fast and easy way to quickly play around with different paces and target race times.

There are tons of race pace calculators out there on the internet already, but I wasn’t happy with any of them. Often I want to quickly iterate on different paces or race times, or toggle back and forth between goal time and goal pace.

For example, if a runner I’m coaching has done some workouts that suggest their marathon pace might be around 6:55–6:48/mi, I often do something like this:

How fast is 6:55/mi for the marathon? It's 3:01:21. What about 6:48/mi? That's 2:58:17. It’d be nice to get under 3:00, how fast is that? It’s 6:52/mi. Is that 6:52 exactly? No it's actually 6:51.9. Ok, let's try some workouts in the next few weeks around 6:51-6:49/mi and see how that pace range feels.

With other race pace calculators, this iteration was just too slow. So, I built this calculator to make it fast and easy to play around like this, even on your smartphone.

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Percy Cerutty’s training philosophy for distance runners, 50 years on

Fifty years ago, on August 14, 1975, the great Australian coach Percy Cerutty passed away in Portsea, Australia—the same sandy, windswept coastal town where he trained some of Australia’s top middle distance runners in the 1950s and 1960s.

Cerutty was best-known for the accomplishments of his coaching charges John Landy and Herb Elliott—Landy being the second person to break four minutes in the mile and a bronze medalist at 1500m at the 1956 Melbourne Olympics, and Herb Elliott being the greatest miler of his day, who at age 22 was Olympic champion, Commonwealth champion, and world-record holder in the mile (3:54.5) and 1500m (3:35.6).

Cerutty also had a longstanding coaching rivalry with New Zealander Arthur Lydiard, whose name would become synonymous with high-mileage training during the 1960s.

Perhaps because Cerutty intentionally eschewed narrowly “systematic” approaches to training, there’s very little discussion of “Cerutty-style” training the way you hear runners discussing “Lydiard-style” training. Cerutty left behind no pre-written workout template, no system of formulas, and little in the way of universal dictums for training.[1] He did, however, leave behind quite a lot of writing.

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Individual variation in aerobic and anaerobic energy contributions to different events

Fast-twitch Frannie and Slow-twitch Sallie face off in an ultimate battle to discover who is truly the queen of the mile

Many books on training and exercise physiology (including mine) begin with a discussion of aerobic and anaerobic energy production. The next logical question to ask is how much these two energy systems contribute to the various running events—how “aerobic” is, say, the 800m? Such a question is sure to spark heated debate online, but I have always been skeptical of such figures, for two reasons.

First, some of the methods that were traditionally used to come up with the aerobic vs. anaerobic contribution to a particular event have not held up to scrutiny.

Take the concept of “oxygen debt”—the idea that you could measure anaerobic energy expenditure by measuring post-exercise oxygen consumption, as your body “paid” for its anaerobic energy production. This concept was known to be shaky as early as 1984, and though later research has improved on the accuracy of these metrics considerably, many of the papers that coaches and training books cite do not use these modern, improved methods.

Second, I have a broader disagreement with the search for one number: to say, for example that the 800m is “65% aerobic” (as Joe Vigil’s book does) or ~50% (as Coe/Martin’s book does) glosses over the fact that there is tremendous individual variation in how much aerobic versus anaerobic energy goes into a given event.[1]

In fact, that range of variation looks like this:

Event % Anaerobic (range for nine out of ten runners)
800m 15–33%
1000m 10–25%
1500m / mile 8–20%
3000m / 2 miles 4–10%
5000m 3–6%
10,000m 2–4%

Where do these numbers come from? Read on to find out!

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Predicting threshold pace, CV pace, and VO2max pace from 5k times

Most serious runners do workouts at threshold pace, CV pace, and VO2max pace. But how can you know if you're running the right pace for your threshold, CV ("critical velocity," a.k.a. critical speed), or VO2max sessions? There are plenty of conversion charts online, but it's not always clear whether they're making predictions that are accurate for most runners.

This article introduces a simple framework for determining threshold, CV, and VO2max pace based off your current 5k fitness, using percentages of 5k pace to set workout paces. Below, I'll show how these three training paces can be derived from the critical speed model, and present an analysis on thousands of race performances that result in the following training guidelines:

Pace Estimate Meaning Also known as
Threshold 90% 5k Fastest pace that produces a metabolic steady-state SSmax, LT2, CS-, T pace
CV pace 96% 5k Boundary separating metabolically sustainable and unsustainable paces CS, critical speed
VO2max pace 100% 5k Slowest speed that produces metabolic instability and drives oxygen consumption to VO2max CS+

Don’t forget that I have a handy pace percentage calculator for quickly calculating pace percentages!

These predictions are accurate for >90% of runners ("accurate" here meaning "producing the intended physiological effects") and come from data on hundreds of runners with 5k PRs from 14:00 to 25:00. They'll probably work pretty well outside that range too.

Naturally, these predictions work great for full-spectrum percentage-based training, but they work just as well in other systems too.

Want to know where these calculations come from? Read on!

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Marius Bakken in his own words: double threshold, lactate testing, altitude, periodization, and more

Double threshold training is one of the hottest topics in distance training right now, with many runners aiming to replicate Jakob Ingebrigtsen's incredible success in the 1500m, 3000m, and 5000m. The double threshold method does not originate with the Ingebrigtsens, though—it was first pioneered by Norwegian 5k runner Marius Bakken.

Marius Bakken’s 2022 blog post on the Norwegian Model of training has become a key resource for English-speaking runners interested in the practical implementation of double threshold training. Aside from that blog post and an excellent 2025 follow-up, though, English-language resources on double threshold training are lacking—most of us have to make do with second-hand recaps of Norwegian-language articles or interviews.

One of the main resources for Norwegian-speaking runners has been Bakken’s appearances on the Norwegian-language podcast I det lange løp (“In the Long Run”). That podcast, which ran from 2019–2023, hosted Marius Bakken several times to talk about double threshold training.

In this blog post, I am presenting what I hope will be another significant English-language resource for understanding the practical use of double threshold training: a translated version of Marius Bakken’s two-part interview on I det lange løp, plus commentary and footnotes.

The interview covers Bakken’s personal training history, the development of the double threshold method, the use of altitude training, intervals versus continuous runs for improving threshold, and more. I also wrote up a short commentary that follows the text of the interview.

Make yourself your favorite beverage and find a comfy spot to sit down, because there is a ton of in-depth training wisdom in this interview—the original interview runs nearly two hours, and even in writing, it’s quite a long read!

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The science of running in super spikes: New data on Nike, Adidas, and PUMA track shoes

Lab scientist holding a prototype track and field super spike

Super spikes are track spikes for middle and long distance events that use the two key innovations in shoe tech that have revolutionized marathon shoes: “super foam” with high deformation and excellent energy return, and carbon fiber plates in the midsole.

I have a longer and more detailed article in the works that takes a deep dive into the biomechanics of super shoes more generally, but I wanted to get this post out since it’s track season and people want to run fast!

The impetus for this post was a fascinating new preprint on the benefits of super spikes from a multi-site collaboration involving research labs in Spain, the US, and Canada. The focus of the study is middle distance performance in super spikes versus traditional spikes.

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A comprehensive overview of Canova-style "full-spectrum" percentage-based training for runners

Percentage-based training, or as I've recently taken to calling it, full-spectrum training, is a mathematical approach to planning workouts for runners. Percentage-based methods are used by many top international coaches, most notably Renato Canova, to train runners at distances from 800m to the marathon. 

I could write a whole book about percentage-based training for runners (in fact, I did write a whole book on full-spectrum percentage-based marathon training), but the goal of this post is to give a clear, comprehensive, and readable overview of percentage-based training as a system—a set of principles that can be used to guide training decisions.

To this end, we’re going to focus on the concepts and rationale behind the percentage-based training method, as opposed to exact training calendars. This post does include an appendix with recommended workouts for every event from 800m to the marathon (even the 3k!), but event-specific full training calendars will be a project for another day.

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Check out my new book on marathon training!