A Half Ironman training plan built from your physiology. Get progressive long-ride and long-run development, recovery weeks, fueling practice, and a taper that adapts to your life
The Half Ironman (1.9 km swim, 90 km bike, 21.1 km run) is where endurance becomes the primary demand. Unlike Olympic distance, you spend significantly more time at sub-threshold intensities, making pacing discipline and energy management critical.
Volume tolerance must be built progressively, recovery weeks become essential rather than optional, and fueling during training and racing becomes a skill you need to practice regularly
At 70.3 training volumes, the body accumulates fatigue faster than at shorter distances. Recovery weeks are built into the plan every 3 to 4 weeks to allow adaptation, reduce injury risk, and prevent the plateau that comes from relentless loading.
Aixsurge schedules recovery weeks automatically based on your training load and adjusts them if life events (vacation, illness, extra stress) create natural recovery periods
Example training weeks for a Half Ironman plan. The balanced week suits athletes with 8 available sessions. The time-crunched week covers the essentials in 6 sessions
| Day | Session | Notes |
|---|---|---|
| Mon | Rest and mobility | Reduce cumulative fatigue |
| Tue | Bike tempo and short run | Race-specific pacing |
| Wed | Swim endurance and technique | Maintain swim frequency |
| Thu | Run threshold/tempo | Sustainable speed |
| Fri | Easy swim and strength | Low stress |
| Sat (AM) | Long bike and brick run | Fueling practice |
| Sat (PM) | — | Recovery |
| Sun | Long run and optional easy spin | Durability focus |
Preview of a half-distance triathlon training plan crafted for athlete with a 0.8 mmol/l VO2max and 0.4 mmol/l VLamax in cycling. The focus of this phase is to enhance strength, and the current week’s sample includes workouts specifically designed to improve athlete’s strength
Warm up
15 min @ 147-159 watts % 80-90 rpm
Repeat 3 times
Cool down
5 min @ 147-159 watts % 80-90 rpm
Have a balanced meal with proteins, fats, and carbs 2 hours before the workout.
Boosts aerobic fitness by promoting increased production of mitochondria, enhancing capillarization around muscles, improving the fatigue resistance of slow-twitch muscle fibers, and training the body to utilize fat more effectively as a primary energy source.
Zone 3 efforts also build aerobic capacity in higher-power muscle fibers and may enhance fatigue resistance by strengthening muscles.
Together, these endurance rides play a key role in improving aerobic capacity, raising lactate threshold, and building muscular endurance.
Complete these blocks at a lower cadence (60-70 rpm) to shift the emphasis to muscle power production and reduce reliance on the cardiovascular system.
Long workouts in the 70.3 plan are designed as fueling practice opportunities. Brick sessions (bike followed by run) simulate race-day demands and train your gut to process nutrition under load.
The plan notes when and what to practice eating during long rides and runs, so your race-day nutrition strategy is rehearsed, not improvised
Training three sports simultaneously creates complex fatigue interactions. A hard bike session affects your run the next day. A long swim can leave your shoulders too fatigued for quality cycling.
The plan sequences workouts to minimize negative interference and maximize the transfer between disciplines. Hard days are followed by easy days or different-discipline sessions, and weekly load is distributed to avoid accumulating fatigue in any single area
How long should I train for 70.3?
16 to 20 weeks is typical for athletes with an existing aerobic base. If you are coming from Olympic distance, 16 weeks is usually sufficient. First-time 70.3 athletes benefit from a longer build of 20 or more weeks.
Can I do this with limited long-ride time?
Yes. The plan adapts to your available hours. If you cannot do a 3+ hour ride on weekends, the plan adjusts intensity and uses structured indoor sessions to build similar physiological adaptations in less time.
How does the plan handle missed workouts?
Aixsurge analyzes your training history and dynamically adjusts the plan. Missed sessions are not crammed into future weeks. Instead, the plan recalculates priorities and adjusts upcoming sessions to keep you on track.
Do I need a power meter for cycling?
Not required, but recommended for 70.3. Power data enables more precise intensity control on long rides, which matters more at this distance. The plan works with heart rate alone but offers additional precision with power.
