The Mona Fartlek: Australia’s Greatest Running Workout

You don’t need a coach. You don’t need a track. You don’t need a carbon-plated shoe collection that costs more than your road bike.

You just need 20 minutes.

The Mona Fartlek has become a legendary rite of passage in Australian running circles. Concocted by Steve Moneghetti - one of the country’s greatest ever marathoners - it is a deceptively simple session that has been making runners faster (and making them suffer) for decades.

And the best part? It still hurts just as much today as it did in the 1980s.

What is the Mona Fartlek?

"Fartlek" is the Swedish word for "speed play," but don't let the word "play" fool you. There is a brutal structure to this madness.

The entire workout lasts exactly 20 minutes. There is no stopping, no standing around checking your watch, and absolutely no scrolling Strava between efforts. You press start, and you don’t stop until the time is up.

The breakdown is simple to remember:

2 × 90 seconds hard / 90 seconds float

4 × 60 seconds hard / 60 seconds float

4 × 30 seconds hard / 30 seconds float

4 × 15 seconds hard / 15 seconds float

The Secret is in the "Float"
The magic - and the misery - of the Mona is in the recovery. Unlike traditional interval training where you walk or slowly jog to catch your breath, the Mona demands an active float.

Your "hard" reps are fast (think 3km to 5km race pace), but your "float" recovery is a steady, honest run - not a jog. You are constantly moving, meaning your heart rate never gets a chance to fully drop. It forces your body to learn how to clear lactate and process fatigue while still maintaining a solid clip.

It's deeply uncomfortable. But that’s the point.

Why It Works

The Mona Fartlek sits perfectly in the sweet spot between raw speed work and threshold training.

The 90 and 60-second efforts teach your mind and muscles how to sustain a hard pace under heavy fatigue.

The 30 and 15-second efforts sharpen your top-end speed, leg turnover, and running economy.

The overall structure yields an incredibly time-efficient aerobic and anaerobic punch.

For multi-sport athletes or cyclists looking to improve their running, it is one of the highest-return workouts you can do. Just one session a week can cause a noticeable shift in your 5km pace without forcing you to completely overhaul your weekly training schedule.

The Rookie Mistake Everyone Makes
The biggest trap of the Mona Fartlek is going too hard, too early.

When you start those first 90-second efforts, your legs feel fresh. You might feel like a hero. But if you sprint the opening reps, you will be crawling, gasping, and regretting your life choices by the time you reach the final 30 and 15-second blocks.

The workout isn't about surviving the first half. It’s about finishing the last 15-second rep just as strong - if not stronger - than the first. Pace yourself. The first few efforts should feel controlled. Fast, but not desperate. Trust us, the fatigue will catch up to you.

Why Cyclists (and Triathletes) Love It

Most cyclists already possess a massive aerobic engine. Your heart and lungs are fully capable of going the distance, but what’s often missing is running-specific fitness, rapid leg turnover, and impact tolerance.

The Mona develops all three simultaneously.

Because it’s only 20 minutes long, it easily fits around a heavy riding schedule without draining your glycogen reserves for days. Better yet, it is completely adaptable. Park, bike path, local oval, or a quiet industrial estate—it doesn't matter. No lane markings or GPS tracks required.

How to Build it Into Your Week

You don't need a high-mileage plan to see results from this. For most everyday athletes, a highly effective running week looks like this:

1 × Mona Fartlek session (The high-intensity anchor)

1 × Mid-week easy run (To build active recovery and consistency)

1 × Weekend longer easy run (To build endurance)

That simple three-run structure is more than enough to move the needle significantly over a 5km or 10km distance. If you're chasing a serious personal best, pair the Mona with consistent weekly mileage and watch your times tumble.

The Verdict

There are more scientific workouts out there. There are certainly more complicated workouts with spreadsheets and heart-rate zone equations. And there are definitely more "Instagrammable" workouts.

But few sessions have earned the enduring respect of the global running community quite like the Mona Fartlek.

Twenty minutes. No excuses. Just you, your lungs, and a rapidly deteriorating sense of optimism.