10×800m Threshold Track Run: High-Volume Speed Endurance

Session Overview

Ten 800m repetitions at threshold pace accumulates 8km of quality running — one of the most demanding track sessions in a triathlete’s training armoury. It builds the lactate clearance capacity that separates strong runners from struggling ones in the final kilometres of a 70.3 or Olympic race. Best placed in a peak-training block, 6–10 weeks before your target event.

What You’ll Need

• Standard 400m running track
• GPS watch or access to a pace clock
• Water bottle trackside
• Racing flats or lightweight trainers recommended

Warm-Up (15 minutes)

2km easy jog at Zone 1–2, followed by 5 minutes of dynamic mobility: leg swings, hip circles, high knees, and butt kicks. Then 4×100m strides at 85% effort with full recovery between each. You should feel loose, warm, and ready to go hard before your first rep.

Main Set

10×800m at threshold pace — approximately your 10km race pace, or 20–30 seconds per km slower than your 5km race pace. Take 90 seconds of easy jogging recovery between each rep. Target: all 10 reps within 5 seconds of your first rep’s time.

• Reps 1–3: Disciplined start — this pace should feel controlled. Resist the urge to go faster
• Reps 4–6: Effort ramps as legs accumulate fatigue; pace must stay locked
• Reps 7–8: Hard zone — RPE 8.5/10. Focus on form: high hips, quick cadence, relaxed arms
• Reps 9–10: Empty the tank — these are the reps that build fitness

Cool-Down (10 minutes)

2km very easy jog or walk-jog until heart rate drops below 130bpm. Follow with 5 minutes of static stretching: quadriceps, hamstrings, hip flexors, and calves. Prioritise recovery nutrition within 30 minutes of finishing.

Coaching Notes

• Your first 800m splits set the benchmark — if rep 1 is 3:30, all 10 should land between 3:28–3:35
• Common mistake: going too fast on reps 1–2 and fading badly in reps 7–10, destroying the aerobic stimulus
• To make it easier: reduce to 8×800m, or extend recovery to 2 minutes
• To make it harder: reduce recovery to 60 seconds, or add a final 400m all-out sprint at the end
• Heart rate should reach Zone 4–5 (85–93% max HR) during each rep — if it stays below Zone 4, you’re running too slowly