Intermediate Half Ironman Plan: Sub-6 Hour Goal
Advanced 70.3 training plan targeting sub-6:00 finish times. Structured intensity, race-pace workouts, and performance-focused preparation.
An intermediate Half Ironman training plan targets sub-6:00 finish times through 10-14 hours of weekly training with structured intensity and race-simulation workouts.
This plan assumes you've completed at least one 70.3 or have a strong Olympic distance background. If you're new to the distance, start with our 16-week beginner plan.
Sub-6:00 Target Splits
To finish under 6 hours, target approximately:
| Discipline | Target Time | Pace/Speed |
|---|---|---|
| Swim 1.9km | 32-38 min | 1:40-2:00/100m |
| T1 | 3-5 min | Efficient |
| Bike 90km | 2:40-3:00 | 30-34 km/h |
| T2 | 2-3 min | Quick |
| Run 21.1km | 1:50-2:05 | 5:15-5:55/km |
| Total | <6:00:00 |
Use our 70.3 Calculator to model your specific targets.
Training Requirements
Weekly Volume
| Week Type | Hours | Sessions |
|---|---|---|
| Standard | 10-12 | 8-10 |
| Recovery | 7-8 | 6-8 |
| Peak | 13-14 | 9-11 |
Intensity Distribution
Following polarized training principles:
- 75-80% Easy/Aerobic (Zone 1-2)
- 5% Tempo/Sweet Spot (Zone 3)
- 15-20% Threshold/Hard (Zone 4-5)
16-Week Plan Overview
Phase Structure
| Weeks | Phase | Focus | Volume |
|---|---|---|---|
| 1-4 | Base Refresh | Aerobic + technique | 9-10 hrs |
| 5-8 | Build 1 | Threshold development | 10-12 hrs |
| 9-12 | Build 2 | Race-specific intensity | 11-13 hrs |
| 13-14 | Peak | Race simulation | 13-14 hrs |
| 15-16 | Taper | Fresh legs | 7-9 hrs |
Key Workouts for Speed
Swim: Threshold Development
CSS Intervals:
Warm-up: 400m mixed
Main: 6 x 300m at CSS pace, 15s rest
OR 4 x 400m at CSS pace, 20s rest
Cool-down: 200m easy
Total: 2,600-2,800m
Race-Pace Session:
Warm-up: 300m
Main: 1,900m at goal race pace
(continuous, include sighting practice)
Cool-down: 200m
Total: 2,400m
Calculate your CSS: CSS Calculator
Bike: Power Development
Sweet Spot Intervals:
Warm-up: 15 min building
Main: 3 x 20 min at 88-93% FTP, 5 min easy
Cool-down: 10 min easy
Total: 90 min
Race Simulation:
Warm-up: 15 min
Main: 2.5-3 hours at goal race watts (72-78% FTP)
Practice full race nutrition
Include 4 x 30s surges
Cool-down: 10 min easy
Total: 2.75-3.25 hours
Over-Under Threshold:
Warm-up: 15 min
Main: 5 x (4 min at 105% FTP + 4 min at 90% FTP)
3 min easy between sets
Cool-down: 10 min
Total: 85 min
Find your FTP: FTP Calculator
Run: Speed Endurance
Tempo Run:
Warm-up: 15 min easy
Main: 35-45 min at half marathon pace
Cool-down: 10 min easy
Total: 60-70 min
Interval Session:
Warm-up: 15 min + strides
Main: 6 x 1km at 10K pace, 90s jog recovery
Cool-down: 10 min easy
Total: ~55 min
Progressive Long Run:
Total: 90-100 min
Structure:
First 60 min: Easy (Zone 2)
Next 20 min: Marathon pace
Final 10-20 min: Half marathon pace
Brick Workouts
Race Simulation Brick:
Bike: 3 hours at race watts (72-78% FTP)
Full race nutrition protocol
T2: Full race transition practice
Run: 45-60 min
First 15 min: Easy, let legs adjust
Next 20 min: Goal race pace
Final 10-25 min: Push if feeling good
Speed Brick:
Bike: 90 min with 4 x 6 min at race watts
T2: Fast transition
Run: 30 min with 4 x 3 min at 10K pace, 2 min easy
Essential reading: Brick Workouts for Triathlon
Sample Training Weeks
Build Phase Week (Week 6)
| Day | Session | Duration | Intensity |
|---|---|---|---|
| Mon | Swim CSS intervals | 55 min | Hard |
| Tue | Run intervals | 55 min | Hard |
| Wed | Bike sweet spot | 90 min | Moderate-Hard |
| Thu | Easy swim | 40 min | Easy |
| Fri | Rest or easy spin | 0-30 min | Very easy |
| Sat | Long brick | 3 hrs + 40 min | Race effort |
| Sun | Long run | 80 min | Easy |
Weekly total: ~11.5 hours
Peak Week (Week 13)
| Day | Session | Duration | Intensity |
|---|---|---|---|
| Mon | Swim race-pace | 60 min | Hard |
| Tue | Run tempo | 65 min | Moderate-Hard |
| Wed | Bike over-unders | 95 min | Hard |
| Thu | Easy swim | 45 min | Easy |
| Fri | Rest | - | - |
| Sat | Race simulation | 3.5 hrs + 55 min | Race effort |
| Sun | Long run (progressive) | 95 min | Building |
Weekly total: ~13.5 hours
Race Execution Strategy
Swim (32-38 min target)
- Start controlled, find rhythm in first 300m
- Sight every 8-10 strokes
- Draft when possible (saves 10-15%)
- Negative split if possible
- Strong exit into T1
Bike (2:40-3:00 target)
Pacing by segment:
| Segment | Power Target | Focus |
|---|---|---|
| km 0-20 | 70-73% FTP | Settle in, don't chase |
| km 20-60 | 73-78% FTP | Steady, sustainable |
| km 60-85 | 73-78% FTP | Maintain despite fatigue |
| km 85-90 | 70-73% FTP | Spin easy, prepare for run |
Nutrition: 70-90g carbs/hour, 500-750ml fluid/hour
Run (1:50-2:05 target)
Pacing strategy:
| Segment | Pace | Strategy |
|---|---|---|
| km 0-3 | +10-15 sec/km | Let legs adapt |
| km 3-10 | Goal pace | Settle into rhythm |
| km 10-18 | Goal pace | Maintain, stay focused |
| km 18-21 | Push | Everything you have |
Read more: Half Ironman Pacing Strategy
Tracking Progress
Benchmark Tests (Every 4 Weeks)
| Discipline | Test | Target Improvement |
|---|---|---|
| Swim | 1,000m time trial | 5-10 sec/month |
| Bike | 20 min power test | 5-8 watts/month |
| Run | 10km time trial | 15-30 sec/month |
Signs of Good Adaptation
- Threshold pace/power increasing
- Same efforts feel slightly easier
- Recovery between sessions faster
- Brick runs feel more natural
- Consistent energy levels
Common Mistakes to Avoid
- Too much intensity: Stick to 80/20 distribution
- Neglecting easy days: Recovery is when you adapt
- Racing every brick: Save race effort for race day
- Pushing bike too hard: 72-78% FTP, not 85%
- Starting run too fast: Patience in first 3km
Calculate Your Race Potential
Use our 70.3 Calculator with your current training data to see if sub-6:00 is achievable.
Related Resources
- 16-Week Beginner Half Ironman Plan - If you need more base
- Half Ironman Pacing Strategy - Race execution
- Threshold Training for Triathlon - Build speed
- Half Ironman Nutrition Plan - Race fueling
- Triathlon Training Zones Explained - Intensity guide