Run-Walk Long Run: 2-Hour Ironman Pacing Session

Session Overview

The run-walk method is not just for beginners — many experienced Ironman athletes and coaches use structured walk breaks in training and racing to preserve muscle fibre integrity over marathon-length efforts. This 2-hour session uses a 9:1 run-walk ratio to build long-run endurance without the deep muscular fatigue of a continuous effort at the same duration.

What You’ll Need

• GPS watch with interval timer or run-walk alert function
• Hydration vest or belt for a 2-hour session
• Energy gels or chews — use to practise race-day fuelling strategy
• Flat or gently rolling route — avoid technical trail for your first run-walk long run

Warm-Up (10 minutes)

Walk briskly for 5 minutes then jog very easily for 5 minutes at RPE 3. This is a long session — no benefit to rushing the warm-up. The first 20 minutes of the main set will naturally feel like an extension of the warm-up, which is exactly right.

Main Set

Repeat a 9-minute run / 1-minute walk cycle for 110 minutes. During run segments hold an easy-to-moderate aerobic pace (RPE 5–6, Zone 2 heart rate). During walk segments, walk purposefully — this is active recovery, not a stop. Use the walk break to drink or take nutrition.

• Cycles 1–5 (first 50 min): Run 9 min at RPE 5, walk 1 min — settle into rhythm
• Cycles 6–9 (next 40 min): Run 9 min at RPE 5–6, walk 1 min — you should feel strong
• Cycles 10–11 (final 20 min): Run 9 min at RPE 6, walk 1 min — small lift is fine if feeling good
• Take a gel or 30g of carbohydrate at 45 and 90 minutes during each walk break

Cool-Down (10 minutes)

Walk for 5–10 minutes and stretch hip flexors, calves, and glutes. Your legs may feel surprisingly fresh compared to a continuous long run of the same duration — this is the point. Faster recovery means you can train again sooner, which compounds over a training block.

Coaching Notes

• Do NOT skip walk breaks because you feel good. They are the training method — the preservation of form late in the run is exactly what you are practising.
• Running pace should be the same at minute 100 as at minute 10. If you slow significantly, reduce your run-to-walk ratio.
• This session uses a 9:1 ratio, suitable for athletes 12+ weeks from their target Ironman. For race day, many athletes use 20:1 or 25:5 depending on pace and fitness.
• Make it harder: extend run segments to 14 minutes with 1-minute walk. Make it easier: use a 4:1 ratio.
• Practise this in your actual race shoes and with race-day nutrition — this session mimics the specifics of Ironman run-leg demands.