Half Marathon Training: 10 Zone 4 / Threshold Workouts

SUMMARY
Zone 4 training (87–93% max HR, RPE 7–8) targets your lactate threshold — the edge of sustainable effort. These sessions build control, resilience, and late-race strength. For half marathon runners, Zone 4 teaches you to stay composed when the pace rises and finish strong without fading.

What Is Zone 4/Threshold Training?

Zone 4 typically ranges between 87–93% of your maximum heart rate and feels like a 7–8 out of 10 on the RPE scale. You’re breathing hard, conversation is gone and focus must stay sharp. It’s the kind of effort that requires management — you can hold it, but only with precision. When you’re in Zone 4, you feel just beneath your limit. You’re pushing with purpose. It’s controlled discomfort and it’s one of the most productive zones for preparing to race well at half marathon intensity.

Why These Sessions Work

Zone 4 workouts increase your lactate threshold, improve fatigue resistance, and develop your ability to run fast with control. These sessions teach you to handle pressure, respond to pacing shifts, and run strong without slipping into overexertion. For half marathoners, this is essential — especially when racing against both distance and time.

10 Threshold Workouts for Half Marathon Runners

1. Standard Threshold Repeats

Repeatable, controlled effort to build strength.

• Warm-Up: 12 min jog + 4 strides

• Main Set: 4 x 8 min @ Zone 4 (2 min jog)

• Cool-Down: 10 min jog

2. Progressive Threshold Blocks

Builds intensity gradually to simulate race fatigue.

• Warm-Up: 15 min jog

• Main Set: 6 min → 8 min → 10 min @ Zone 4 (90 sec jog between)

• Cool-Down: 10 min jog

3. Broken Threshold Sets

Maintains high effort without overloading.

• Warm-Up: 12 min jog + drills

• Main Set: 3 x (5 min + 3 min) @ Zone 4 (1 min between reps, 2 min between sets)

• Cool-Down: 10 min jog

4. Threshold + Tempo Blend

Transitions from steady effort into race-like intensity.

• Warm-Up: 12 min jog

• Main Set:
  10 min @ Zone 3
  2 x 7 min @ Zone 4 (2 min jog)

• Cool-Down: 10 min jog

5. Long Threshold Repeats

Pushes your ability to hold form over longer efforts.

• Warm-Up: 15 min jog

• Main Set: 2 x 12 min @ Zone 4 (3 min jog)

• Cool-Down: 10 min jog

6. Fast Finish Threshold

Trains control early, strength late.

• Warm-Up: 12 min jog

• Main Set: 10 min steady → 8 min @ Zone 3 → 4 min @ Zone 4

• Cool-Down: 10 min jog

7. Short Threshold Intervals

Sharp and focused, with active recovery.

• Warm-Up: 10 min jog

• Main Set: 6 x 4 min @ Zone 4 (90 sec jog)

• Cool-Down: 10 min jog

8. Hill Threshold Session

Builds strength while staying at controlled intensity.

• Warm-Up: 15 min jog + hill drills

• Main Set: 5 x 4 min uphill @ Zone 4 (walk/jog down)

• Cool-Down: 10 min jog

9. Threshold Pyramid

Balances pacing and effort through varied lengths.

• Warm-Up: 15 min jog

• Main Set: 5 min → 6 min → 7 min → 6 min → 5 min @ Zone 4 (2 min jog)

• Cool-Down: 10 min jog

10. 90-Second Threshold Repeats

Adds volume without overreaching.

• Warm-Up: 10 min jog

• Main Set: 10 x 90 sec @ Zone 4 (60 sec jog)

• Cool-Down: 10 min jog

FAQ: Zone 4 / Threshold Training and for Half Marathon

How do I know I’m in Zone 4?

You’re breathing hard and focused. You can’t talk. It feels like you’re holding just below your limit — strong, but needing control to stay there.

How often should I train in Zone 4 during a half marathon build?

One session per week is effective. Add a second only if recovery, volume, and training experience allow.

How do I calculate my Zone 4 heart rate?

Use FLJUGA’s free heart rate zone calculator to find your personalised ranges and train with precision.

Final Thoughts

Zone 4 is where controlled speed becomes race-ready. These sessions prepare you for the demands of racing hard over distance — not with chaos, but with composure. When the pace picks up, or the hill hits, or the line approaches, Zone 4 is what helps you respond without breaking.

Can you hold strong when your race starts to press back?

Always consult with a medical professional or certified coach before beginning any new training program. The information provided is for educational purposes only and is not a substitute for personalized advice.