Quick Answer
Fartlek = “speed play” in Swedish. Continuous running with alternating hard efforts and easy recovery jogs — never stops. More flexible than intervals; higher average HR than intervals because recovery never drops as low. Best used once per week as a quality session. Can be unstructured (landmark-to-landmark) or structured (timed efforts). Suitable from beginners to elite runners.
What Fartlek Is — and Where It Came From
Fartlek was developed in the late 1930s by Gösta Holmér, a Swedish Olympian and national athletics coach, as a deliberate response to Finland’s domination of international distance running at the time. Holmér’s insight was that Swedish runners needed to train speed without abandoning the continuous aerobic base that distinguished endurance running from track sprinting. The solution: blend them together. Run continuously, but spontaneously vary the pace — surge up a hill, sprint to a landmark, float the recovery, then surge again. “Fartlek” in Swedish means “speed play,” and the name captures the spirit of the method accurately.
The approach spread globally through influential coaches of the mid-20th century who adapted it to their own contexts. Percy Cerutty, who coached Australian runners at his legendary Portsea camp through the 1950s and 1960s, used fartlek extensively in his terrain-based training — including sprinting up sand dunes “as high as 80 feet and as steeply graded as the stairs up the Statue of Liberty.” Arthur Lydiard in New Zealand incorporated fartlek-type sessions over varied trails as part of his aerobic base development methodology. In the United States, Doris Brown Heritage — Track and Field Hall of Fame inductee — structured fartlek into 20-minute sessions with short sprints and 5–7 minute effort segments for her university cross-country runners.
Australia produced one of the most famous structured fartlek workouts in running: the Moneghetti fartlek, named after elite distance runner Steve Moneghetti and devised by his coach Chris Wardlaw. This 20-minute structured session — covered in full below — remains one of the most practical and widely used fartlek formats in the world.
Fartlek vs Intervals vs Tempo: The Key Differences
These three are frequently confused because all involve running faster than easy pace. The distinctions matter for understanding what each develops and when to use them.
Fartlek: Continuous running throughout — the runner never stops or walks, even during recovery. Variable effort and duration, either by feel or by a predetermined (but flexible) structure. Recovery is active jogging that keeps the heart rate elevated. Because heart rate never drops fully, the average cardiovascular load across a fartlek session is typically higher than an equivalent interval session, even though the hard efforts may be shorter or less intense. Develops both aerobic and anaerobic systems simultaneously. The continuous nature builds lactate tolerance — the body must clear lactate while still running at recovery pace, which is a more race-specific skill than clearing lactate during a complete stop.
Intervals: Structured hard efforts with defined distances, times, and recovery periods. Recovery can be a complete stop, walk, or jog — allowing the cardiovascular system to drop to a lower state before the next effort. This permits higher quality on each individual interval than fartlek allows, making intervals more effective for targeting specific physiological zones like VO2max or lactate threshold with precision. Our VO2 max workouts guide and lactate threshold guide cover structured interval formats that achieve these specific adaptations.
Tempo: A single sustained effort at a constant pace (lactate threshold effort — approximately 10K pace for recreational runners) without pace changes. There is no “speed play” in tempo — it’s one intensity maintained throughout the main set. Tempo develops the ability to sustain a specific hard pace, while fartlek develops the ability to change gears and recover while still moving.
The practical positioning: tempo and intervals are both more precise; fartlek is more flexible. Use fartlek when training is in a base phase or transitional phase, when variety is needed after a stretch of structured sessions, or when the terrain (hills, trails, parks) naturally creates variation that makes formal structure awkward. Our complete speed work guide covers how all three fit within a structured training week.
The Two Types of Fartlek: Unstructured and Structured
Unstructured (classic) fartlek is the original form — truly self-directed speed play. The runner surges when they feel like it, recovers when they need to, uses landmarks, hills, and terrain as the cues for effort changes rather than a watch. Sprint to that bench, jog to the crossing, surge up the hill, float the flat, pick it up past the playground. There is no predetermined plan. The session ends when the runner decides it’s done. This is the form closest to Holmér’s original intent — playful, spontaneous, enjoyable.
Structured fartlek applies predetermined time targets to the surges and recoveries while maintaining the continuous-running format. “Run hard for 2 minutes, jog for 2 minutes, repeat 5 times” is a structured fartlek. The Moneghetti fartlek (described below) is the most famous structured variant. Structured fartlek is more predictable and produces more consistent training load, making it easier to track progress and assign to athletes who need precise guidance. It sits between true fartlek and intervals on the structure spectrum.
For most recreational runners, the most effective approach is a mix of both: occasional unstructured sessions for mental freshness and enjoyment, with structured formats when a specific physiological target is needed.
6 Fartlek Training Examples
1. Beginner Landmark Fartlek (20–25 minutes total)
The starting point for runners new to any kind of speed work. No watch, no plan — just eyes on the environment. Warm up with 5–8 minutes of easy jogging. Then: surge to the next lamppost, bench, tree, or parked car. When you reach it, drop to easy jog and recover until your breathing is comfortable — this might be 30 seconds or 2 minutes, it doesn’t matter. Surge to the next landmark. Continue for 12–15 minutes. Cool down with 5 minutes easy jogging. This session has no defined intensity, no defined distance — just the principle of running faster than easy, then recovering, without stopping. It’s the cleanest introduction to speed work available. Our beginner running guide covers the base fitness that should be established before adding any form of speed play.
2. Classic Timed Fartlek (30–35 minutes total)
A simple structured session appropriate from intermediate beginners upward. Warm up 10 minutes easy. Main set: 1 minute hard / 1 minute easy jog × 3 rounds; then 2 minutes hard / 2 minutes easy × 3 rounds; then 1 minute hard / 1 minute easy × 2 rounds. Total hard work: 15 minutes. Cool down 5 minutes easy. Hard efforts should be at a pace that feels like 7–8 out of 10 effort — challenging but not maximal. The 1-minute efforts will naturally be faster than the 2-minute efforts at the same perceived effort, which is correct and expected. This session trains the body to change gears repeatedly across different durations — a direct race preparation skill.
3. The Moneghetti Fartlek (40 minutes total)
Devised by Australian coach Chris Wardlaw for elite distance runner Steve Moneghetti, this 20-minute structured session became one of the most replicated fartlek workouts in the world. It is a descending ladder of efforts — as the efforts shorten, the pace increases.
Warm-up: 10 minutes easy running. Main set: 2 × 90 seconds hard / 90 seconds easy jog → 4 × 60 seconds hard / 60 seconds easy jog → 4 × 30 seconds hard / 30 seconds easy jog → 4 × 15 seconds hard / 15 seconds easy jog. Cool-down: 10 minutes easy running. Total hard work: 14 minutes. Total recovery: 6 minutes. Total session: 40 minutes including warm-up and cool-down.
The key principle: the 90-second efforts are run at approximately threshold effort (hard but sustainable); the 15-second efforts are much faster — approaching sprint pace. As the Wikipedia entry on fartlek notes, “a stated assumption of the workout is that as the period of effort shortens, the intensity of the effort increases.” This creates a session that develops both threshold capacity and top-end neuromuscular speed within a single continuous run. It sits at the intersection of structure and play — every runner knows exactly what’s coming, but the increasing pace of the short efforts keeps the session mentally sharp throughout.
4. Hill Fartlek (30–45 minutes total)
The terrain-based version closest to Cerutty’s Portsea training. Run easy on flat or gently rolling terrain. When a hill appears — or when you choose to surge up a gradient — run it hard. Use the downhill or the next flat section as recovery. Choose the next hill and surge again. No timing, no distances — just the hills as the workout structure. The gradient forces intensity naturally; the body works harder without requiring conscious pace manipulation.
This fartlek develops the posterior chain strength (glutes, hamstrings) and foot strike mechanics that flat fartlek doesn’t demand. It also prepares runners for the surges and recovery periods that hilly road races and cross-country courses require. Our hill running guide covers the technique for efficient uphill and downhill running that makes hill fartlek both safer and more effective.
For a more structured hill variation: 8–10 × 30-second hard uphills on a 4–8% gradient, jogging the downhill recovery. Total session 35–40 minutes including warm-up and cool-down.
5. Threshold Fartlek (40–50 minutes total)
An intermediate-to-advanced session that brings fartlek structure closer to structured threshold intervals while retaining continuous movement. Warm up 10–12 minutes easy. Main set: 5 minutes at threshold effort (approximately 10K race pace for recreational runners) / 2 minutes easy jog → 4 minutes at threshold / 2 minutes easy → 3 minutes at threshold / 2 minutes easy → 2 minutes slightly faster than threshold / 2 minutes easy → 90 seconds hard / 90 seconds easy. Cool down 8–10 minutes easy. Total threshold work: ~16 minutes. Total session: 45–50 minutes.
This session develops lactate threshold — the same physiological target as a classic tempo run — but uses the descending format and active recovery of fartlek rather than one continuous tempo block. The jog recovery periods allow slightly higher quality across all the hard efforts than a single 16-minute continuous tempo would. It also builds the ability to resume threshold effort after a period of relative recovery — directly relevant to race surges and the varying pace demands of cross-country and road racing.
6. Long-Run Fartlek (60–90 minutes total)
A marathon-specific tool that teaches pace changes on tired legs — one of the most underused fartlek formats. The session is a standard easy long run with a specific fartlek component built into the final third: after running easy for 40–60 minutes, insert 4–6 × 60-second surges at 10K effort, with 2–3 minutes of easy recovery jog between each surge. The remaining run after the surges is completed at easy pace. Total surge work: 4–6 minutes. The rest of the run is genuinely easy.
The value is entirely in the context: running faster than easy pace with 40–60km of accumulated fatigue in the legs. This trains the body to change gears when depleted — exactly what the final 10km of a marathon demands. It also develops the aerobic base without requiring a separate quality session on a separate day. Our guide on building mileage safely covers how to progressively introduce long-run fartlek components as the long run distance grows.
Fartlek in the Training Week
| Runner level | Recommended use | Frequency | Best session |
|---|---|---|---|
| Beginner | First introduction to speed work; replace formal intervals until base is established | Once per week | Landmark fartlek (unstructured) |
| Intermediate (5K–10K focus) | Rotate with track intervals; use in base phase and early build phase | Once per week | Classic timed fartlek or Moneghetti fartlek |
| Intermediate (half marathon focus) | Replace one threshold session per fortnight; build lactate tolerance | Once per week | Threshold fartlek |
| Advanced (marathon) | Long-run surges; hill fartlek in base phase | 1–2 per week | Long-run fartlek + hill fartlek |
| All levels | Base phase variety; mental freshness; terrain training | Once per week | Hill fartlek (unstructured) |
Fartlek works best when it replaces one structured interval or tempo session rather than being added on top of a full quality training week. Treat it as a quality session — sandwich it between easy running days, warm up properly, and cool down with at least 5–10 minutes of easy jogging. Our warm-up and cool-down guide covers the dynamic warm-up routine that prepares muscles for the immediate speed changes fartlek demands, particularly if the session starts with short, fast efforts rather than a gradually building intensity.
In the base phase — the period of building easy mileage before structured speed work begins — fartlek is the ideal quality session because it introduces aerobic and anaerobic stimulus without the rigid load of track intervals. Our easy run guide covers the effort level that should characterise the recovery jogs within fartlek — genuinely conversational, not just slightly slower than the hard efforts. The quality of recovery jogging during fartlek directly determines how well the hard efforts can be sustained.
Adding strides to easy runs provides a neuromuscular complement to fartlek — short, controlled accelerations that develop leg speed and efficiency without aerobic fatigue. Our strides guide covers the difference between strides (controlled, relaxed speed) and fartlek surges (sustained effort), and how both fit within a training week without conflicting with each other.
Put Fartlek Into a Structured Training Plan
SportCoaching's running training plans sequence fartlek sessions, threshold work, and intervals in the right order through every training week — so quality sessions are supported by appropriate recovery rather than stacked randomly.
FAQ: Fartlek Training
What is fartlek training in running?
Continuous running that alternates between faster efforts and easy recovery jogging — the runner never stops. Developed in the 1930s by Swedish coach Gösta Holmér; “fartlek” means “speed play” in Swedish. Can be unstructured (landmark-to-landmark) or structured (timed efforts). Develops both aerobic and anaerobic fitness simultaneously; average HR is often higher than intervals because recovery never drops fully.
What is the difference between fartlek and interval training?
Recovery: fartlek recovery is active jogging (never stops); intervals can recover completely. This means fartlek maintains continuous cardiovascular load while intervals allow full recovery between hard efforts. Fartlek is more flexible; intervals are more precise for targeting specific zones.
How long should a fartlek session be?
Beginners: 20–30 minutes total including warm-up and cool-down, with 10–15 minutes of speed play. Intermediate: 30–45 minutes. Advanced: 45–75 minutes, including long-run fartlek options. Quality of pace changes matters more than total duration.
What is the Moneghetti fartlek?
A famous Australian structured fartlek: 2 × 90sec hard/90sec easy, then 4 × 60sec/60sec, then 4 × 30sec/30sec, then 4 × 15sec/15sec. 20 minutes of work total, with effort increasing as duration decreases. Warm-up and cool-down of 10 minutes each. Named after Steve Moneghetti, devised by coach Chris Wardlaw.
How often should runners do fartlek training?
Once per week as a quality session, replacing one interval or tempo session. Advanced runners may do two: one structured and one informal surge session within a longer easy run. Easy running on either side supports recovery quality.
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