The Training Session That Builds Real Speed on the Run
The Training Session That Builds Real Speed on the Run
If you've been running consistently but feel like your pace has plateaued, there's a good chance you're missing one specific session from your training week: the tempo run. It's one of the most effective workouts in endurance sports — and one of the most misunderstood. Run it too fast and it becomes an interval session. Too slow and it's just a long easy run. Get it right, and it's the session that unlocks genuine, lasting performance gains.
What Is a Tempo Run?
A tempo run is a sustained effort at threshold pace — the point just below where fatigue begins to accumulate rapidly. Think of it as the pace you could realistically hold in a race for around 45 to 60 minutes. It's not a sprint. It's not a jog. It's a controlled, purposeful effort that teaches your body to sustain harder work for longer.
The defining characteristic is that it sits just below your lactate threshold — the intensity at which lactate starts to build in the bloodstream faster than your body can clear it. Training at this level repeatedly pushes that threshold higher, meaning you can run faster for longer before fatigue takes hold.
Why Tempo Runs Work
Tempo runs are effective across a broad range of distances and disciplines. Whether you're preparing for a 5K or lining up for a marathon, they deliver three core adaptations:
Build endurance — sustained efforts at threshold pace condition your aerobic system to handle greater training loads
Raise your lactate threshold — your body becomes more efficient at clearing lactate, so you can hold harder paces without accumulating fatigue
Sharpen mental focus — maintaining controlled discomfort over 20 to 30 minutes builds the mental discipline that translates directly to race day
How a Tempo Run Should Feel
The classic description is "comfortably hard". You're working — there's no doubt about that — but you're not gasping. A useful practical test: you can still think clearly, but holding a full conversation is off the table.
In physiological terms, you're targeting around 85–90% of your maximum heart rate. You should finish a tempo run feeling strong, not destroyed. If you're crawling to the finish, you went too hard. If you feel like you could have run another hour, you didn't push enough.
The Two Most Common Tempo Run Mistakes
Most runners make one of two errors:
Too fast — and you've essentially turned it into an interval session. You'll accumulate too much fatigue and undermine the rest of your training week
Too slow — and it's just a moderate easy run. The threshold stimulus simply isn't there
The goal is to stay just below your red zone. Controlled discomfort, not maximum effort.
How to Pace a Tempo Run
If you're not sure where to start, use your recent 10K time as a reference point. Your tempo pace should sit roughly 15–20 seconds per kilometre slower than your 10K race pace.
For example: a 50-minute 10K runner (5:00/km pace) would target around 5:15–5:20/km for a tempo effort. You can also guide your session by feel or heart rate if you don't have a recent race benchmark — aim for that 85–90% heart rate range and the "can think, can't talk" test.
A Simple Tempo Session to Try
If you're new to tempo training, this is a solid, repeatable structure to build from:
Warm-up: 15 minutes easy running
Tempo block: 20–25 minutes at threshold pace
Cool-down: 10 minutes easy running
Strides during the warm-up or cool-down are optional, but can help prime the legs and improve running economy over time.
Tempo Runs vs Threshold Sessions: What's the Difference?
The two terms are often used interchangeably, but there is a meaningful distinction worth understanding.
A tempo run is a continuous, steady-state effort held at or just below lactate threshold for 20–40 minutes. The pace is consistent throughout — that sustained, controlled effort described above.
A threshold session is a broader term covering any training designed to raise your lactate threshold. That includes tempo runs, but also broken-up interval formats — for example, 3 × 10 minutes at threshold pace with short recovery jogs between. These are sometimes called cruise intervals.
In short: all tempo runs are threshold sessions, but not all threshold sessions are tempo runs. The interval-based version is often easier to execute correctly — the short recoveries help you reset and hold the right pace, making it a useful entry point if you find a solid 25-minute continuous tempo block hard to sustain without drifting.
Intensity Differences
Both sit in a similar zone, but there is a subtle distinction:
Tempo — typically 85–90% max heart rate. Just below the point where lactate accumulates rapidly. Comfortably hard
Threshold intervals — can nudge slightly higher, 88–92% max heart rate. The short recoveries allow you to push a fraction harder than you could sustain continuously, while keeping overall fatigue in check
For broader context, here is where both sit across the full intensity spectrum:
Easy / recovery — 60–70% max HR
Aerobic base — 70–80% max HR
Tempo — 85–90% max HR
Threshold intervals — 88–92% max HR
VO2 max intervals — 92–97% max HR
Sprints / anaerobic — 97–100% max HR
The overlap between tempo and threshold is real — they are neighbouring zones, not distinct ones. Continuous tempo trains your ability to sustain that effort mentally and physically. Threshold intervals let you accumulate more total time in the zone across a single session, often with slightly better pace quality.
Fuelling Your Tempo Run
At threshold intensity, your body is burning through carbohydrate stores at a meaningful rate. For sessions under 45 minutes you may not need to fuel during the run itself, but pre-session nutrition matters. A natural energy bar 60–90 minutes beforehand — something like a Veloforte Classico, with 40g of carbohydrates from real food ingredients — gives you a steady platform to perform from without the risk of GI discomfort at higher intensities.
If your tempo block extends beyond 30 minutes, or you're doing back-to-back sessions, consider an energy gel during the effort or a recovery drink with protein and carbohydrates immediately after.
Not sure how to fuel your specific training load? The Endurance Kollective Fuel App generates a personalised fuelling plan based on your session type, duration, and intensity. Try it at fuel-ready-go.base44.app.
The Bottom Line
Tempo runs are one of the most time-efficient sessions you can add to your training week. Done correctly — once a week, at genuine threshold pace, with proper structure — they're the primary driver of improved lactate threshold and sustained race-day speed. One session per week is enough for most runners. The key is consistency and patience: the adaptations are cumulative, and they compound over months, not days.
Train with intention. Run with control. Progress with purpose.