70.3 Training Plan: 16-Week Guide to Your First Half Ironman
A structured 16-week training plan for Ironman 70.3 — swim/bike/run schedule, brick workouts, taper strategy, and race-day pacing.
Table of Contents
The 70.3 Sweet Spot
The Ironman 70.3 (1.9km swim, 90km bike, 21.1km run) is the most popular triathlon distance in the world — and for good reason. It’s long enough to require serious training and race-day strategy, but short enough that recovery takes days, not weeks. Most finishers complete it in 4:30–7:00.
This 16-week plan is for athletes who can already swim 1000m, ride 90 minutes, and run 45 minutes continuously.
Plan Overview
| Phase | Weeks | Focus | Weekly Hours |
|---|---|---|---|
| Base | 1–6 | Aerobic foundation, technique | 6–9h |
| Build | 7–11 | Race-specific intensity, bricks | 9–12h |
| Peak | 12–14 | Longest sessions, race simulation | 11–14h |
| Taper | 15–16 | Volume reduction, sharpening | 5–8h |
Weekly Template
Base Phase (Weeks 1–6)
| Day | Session | Duration |
|---|---|---|
| Mon | Rest | — |
| Tue | Swim: Technique + endurance | 40–50 min |
| Wed | Bike: Steady aerobic | 60–75 min |
| Thu | Run: Easy aerobic | 35–45 min |
| Fri | Swim: Drills + threshold | 40 min |
| Sat | Long bike | 1.5–2.5h (build weekly) |
| Sun | Long run | 50–75 min (build weekly) |
Build Phase (Weeks 7–11)
| Day | Session | Duration |
|---|---|---|
| Mon | Rest | — |
| Tue | Swim: Threshold intervals (5×200m) | 50 min |
| Wed | Bike: Tempo intervals | 75–90 min |
| Thu | Run: Tempo run | 40–50 min |
| Fri | Swim: Open water or endurance | 45 min |
| Sat | Brick: Bike → Run | 90min bike + 30min run |
| Sun | Long run | 75–100 min |
Peak Phase (Weeks 12–14)
| Day | Session | Duration |
|---|---|---|
| Mon | Rest | — |
| Tue | Swim: Race-pace (1500m continuous) | 50 min |
| Wed | Bike: Race simulation | 90–120 min |
| Thu | Run: Race-pace intervals | 50 min |
| Fri | Easy swim | 30 min |
| Sat | Brick: Long bike → Half-marathon pace run | 2–2.5h bike + 40min run |
| Sun | Long run with race-pace segments | 90–105 min |
Taper (Weeks 15–16)
| Day | Session | Duration |
|---|---|---|
| Mon | Rest | — |
| Tue | Swim: Easy + a few race-pace efforts | 35 min |
| Wed | Bike: Easy spin with 3×3min at race effort | 45 min |
| Thu | Run: Easy with 4×1min at race pace | 30 min |
| Fri | Rest or easy swim | 20 min |
| Sat | Short brick: 30min bike + 15min run (easy) | 45 min |
| Sun (race week) | Race day | — |
Key Workouts Explained
The Saturday Brick
This is the most important workout in 70.3 training. You’ll build from a 60-min bike + 15-min run in the base phase to a 2.5h bike + 40-min run in peak phase. Practice T2 transition, race nutrition, and mental toughness.
The Long Run
Build from 50 minutes to 105 minutes (but never longer — you’re not training for a standalone marathon). In peak phase, include 20–30 minutes at target half-marathon pace in the middle of the long run.
Threshold Swim Sets
- Base: 8×100m at threshold with 15s rest
- Build: 5×200m at threshold with 20s rest
- Peak: 3×400m at race pace with 30s rest
Race-Day Pacing
Swim (Target: 35–45 min)
- Easy first 200m — let the field thin out
- Settle into a sustainable rhythm
- Sight every 8 strokes
- Draft if possible
Bike (Target: 2:30–3:15)
- First 10km: deliberately easy (let heart rate settle from swim)
- Km 10–70: steady race effort (RPE 6–7, or 75–82% FTP)
- Last 20km: maintain effort, don’t surge
- Eat every 20 minutes: 60–80g carbs/hour
Run (Target: 1:45–2:30)
- Walk T2 aid station, take a gel
- First 2km: easy — let legs adjust from the bike
- Km 2–15: settle into target half-marathon pace
- Last 5km: if you feel good, pick it up slightly. If not, just maintain.
- Walk aid stations to drink — it’s faster than trying to run and drink
Common 70.3 Mistakes
- Biking too hard. If you can’t run at your target pace after the bike, you biked too hard. Period.
- Not practicing nutrition. Test your race-day fuelling on every brick and long ride.
- Ignoring the swim. 3 swims per week minimum. The swim sets up your entire race — a panicked swim means an elevated heart rate for the first 30km of the bike.
- Long runs over 2 hours. You don’t need marathon-length runs for a half marathon off the bike. Keep long runs under 105 min and focus on quality.
- Skipping taper. The fitness is banked by week 14. Weeks 15–16 are about arriving fresh, not getting fitter.
Generate your personalized 70.3 plan on our Training Plan page.