Half-IRONMAN Training Plans: How to Prepare for Your First 70.3

A 3-month half-IRONMAN training plan is ideal for triathletes who already have a solid endurance base but are transitioning from Olympic-distance racing. It allows enough time to extend long runs and rides while including race-specific work. It is also a realistic timeline for those with good cycling or running fitness who need to work on their weaker disciplines.

In this plan, you will train around 9-11 hours per week, with a peak of around 12-13 hours. Consistency is vital, and because the timeline is shorter, it is best to begin this plan already able to swim 1 km, ride 2 hours, and run 8-10 km comfortably.

As the weeks progress, the Saturday long bike gradually increases to 3.5-4 hours, and the Sunday run moves closer to 18 km. Brick sessions can replace some of your Sunday long runs, especially in the final four weeks, to ensure smooth transitions from biking to running.

This 6-month half-IRONMAN training plan is the most popular choice for first-time athletes. It allows you enough time to build endurance gradually, thereby reducing the risk of injury and burnout. The plan is designed for beginners with some background in running, cycling, or swimming, but not necessarily experience in all three.

Training time starts around 6-8 hours per week and gradually builds to 12-14 hours at peak. This plan offers flexibility for individuals with busy schedules and ensures a gradual increase in volume.

Because the timeframe is longer, you can repeat base training blocks to reinforce fitness before progressing. This plan is ideal for those who want to feel confident and prepared.

Weekly schedule examples (swim, bike, run, strength)

While each plan differs in length, the structure of a typical week remains much the same.

Most athletes will complete:

• Two swims: one focused on technique and drills, the other on steady endurance.

• Two to three bike rides: usually a long ride, a tempo or threshold ride, and sometimes a brick.

• Two runs: one long run and one shorter run or brick.

• One strength or mobility session: focusing on injury prevention.

• One full rest day: crucial for recovery.

Balancing intensity and recovery is key. You should not feel exhausted all the time. Instead, you should finish most sessions feeling like you could have done more. This way ensures you can complete the next workout and continue to improve.

Cycling prep with ROUVY

Long endurance rides indoors

Long rides are the backbone of every half IRONMAN training plan. However, weather, traffic, and time constraints often make outdoor rides difficult. ROUVY solves this by allowing you to complete long endurance sessions indoors on your smart trainer or smart bike. You can ride real video routes from around the world, making indoor riding engaging and realistic.

This training method is great for busy athletes. You can start your sessions quickly without hours of prep for outdoor rides. Even long rides of three to four hours can be more enjoyable indoors and equate to around 70% of what you’d need to do outside, with no distractions and constant pedalling.

Pacing climbs and virtual routes

Pacing is often the biggest challenge for beginners. On race day, it is easy to push too hard early on and on climbs, especially if you are excited or caught up with faster riders. Using ROUVY’s course simulations, you can practise holding steady power outputs across varied terrain. If your race is on a hilly course, riding a similar virtual profile ahead of time helps you prepare mentally and physically.

You can also perform virtual recons of actual IRONMAN 70.3 routes if they are available. Doing recons reduces uncertainty and builds confidence because you know what to expect on race day.

Structured workouts for speed and consistency

In addition to free-riding, ROUVY offers structured workout sessions that target endurance, tempo, threshold, or VO2 max. These workouts help you build the specific fitness required for a 70.3 bike leg. They also remove the guesswork, guiding you through precise intervals and recovery periods. Many find that following structured sessions indoors is more efficient than trying to replicate them outside, where terrain and traffic often interfere with their training.

Swim and run preparation

Swim drills for open-water confidence

For many first-time triathletes, the swim is the most daunting part of the event. Pool fitness does not always translate directly to open water. That is why swim drills should be included in your half IRONMAN training program. Focus on sighting (lifting your head to look forward without losing rhythm), bilateral breathing (to both sides), and maintaining a relaxed stroke over distance.

Practice in open water before race day. Lakes, rivers, or the sea all help you get used to swimming without pool walls, and to managing nerves in a crowded start. Wearing your wetsuit in training also enables you to adjust to the buoyancy and shoulder restriction.

Long runs and brick sessions (bike-to-run)

Running well off the bike is one of the most challenging aspects of triathlon. Even experienced runners struggle when their legs feel heavy after 90 km of cycling, and this is why brick sessions are so important. A typical brick might be a two-hour bike ride, followed immediately by a 20- to 40-minute run. Over time, your body becomes used to it and adapts, making the transition smoother.

The long run is equally important. Most half-IRONMAN training plans include weekly runs that build up to 16-18 km. These should be steady, aerobic runs, not all-out efforts. Save speed for shorter runs or intervals. The key is to finish long runs feeling strong, not exhausted.

Strength training and mobility work

Core, flexibility and injury prevention

Strength training is often overlooked in triathlon, but it is a vital part of staying injury-free.Core strength helps you maintain posture in the aero position on the bike and supports efficient running form. Glute activation prevents overuse injuries in the hips and knees. Shoulder strength aids swimming endurance.

You don’t need to spend a lot of time in the gym. Just two 30-minute workouts each week, incorporating bodyweight exercises, resistance bands, or light weights, are sufficient. Adding yoga or mobility exercises will help keep your hips and lower back flexible. These small-time investments will improve your strength and endurance over time.

Half-IRONMAN nutrition plan

Daily fuelling during training

Nutrition is the fourth discipline of triathlon. Training volume increases your energy demands, so fuelling well is essential. A balanced diet consisting of complex carbohydrates, lean protein, and healthy fats will support both recovery and performance. Many beginners make the mistake of under-eating during intense training weeks, which can lead to fatigue and poor adaptation.

Think of food as fuel. Before workouts, prioritise carbohydrates to provide energy. After workouts, aim for a mix of carbs and protein to replenish glycogen and repair muscles. Hydration throughout the day also matters, not just during training.

Race-day nutrition: gels, hydration, solids

On race day, the nutrition strategy is different. The general rule is 60-90 grams of carbohydrates per hour, especially during cycling. Nutrition can come from energy gels, sports drinks, and small solid foods, such as bars or chews. The bike leg is the best place to take in fuel, because it is harder to digest while running.

During the run, athletes usually rely on gels, chews, or drinks, experimenting in training to find what their stomach tolerates best. Electrolytes are also crucial, especially in hot conditions, to replace sodium lost through sweat.

Practising nutrition to avoid GI issues

Never leave nutrition until race day. Gastrointestinal issues like cramping, bloating, or nausea are among the top reasons beginners fail to complete the program. Use your long rides and brick sessions to practise your half IRONMAN nutrition plan exactly as you plan to on race day. Test various gels, drinks, and timing conditions to get the best results. The goal is to arrive on the start line knowing what works for you.

Gear checklist for 70.3

Swim: wetsuit, goggles

A triathlon-approved wetsuit helps you stay buoyant and warm in open water. Choose one that fits snugly but does not restrict your shoulders. Bring tinted goggles if your race is outdoors.

Bike: road vs tri bike, trainer

Both road bikes and triathlon-specific bikes are allowed. A tri bike provides aerodynamic advantages, but many beginners use a road bike with clip-on aero bars. Whichever you choose, ensure it is comfortable and set up correctly. A smart trainer paired with ROUVY is invaluable for practising your time-trial position when training indoors.

Run: shoes, essentials

Choose running shoes that you have tested on long runs. Race day is not the time to break in a new pair of shoes. Lightweight yet cushioned shoes are ideal for a half-marathon distance. Some athletes prefer elastic laces for quick transitions.

Transition must-haves

Lay out your transition area with care. Essentials include a towel, helmet, cycling shoes, race belt, running cap, and hydration bottles. Practise transitions in training so you know the sequence by heart.

Race-day strategy and mental prep

Pacing across all three disciplines

Your race pace strategy should focus on maintaining a steady effort throughout. Swim at a comfortable pace to prevent fatigue, bike steadily while fueling yourself, and try to run consistently without too many stops. Beginners may find heart rate monitors or power meters helpful in keeping their effort in check.

Managing nerves and mental fatigue

Mental preparation is just as important as physical. It is normal to feel nervous at the start line, but visualising breaking the race into small parts helps. Focus on one buoy at a time in the swim, one aid station at a time on the bike, and one kilometre at a time on the run. Visualisation techniques in training can also build confidence. Remind yourself that you have prepared and that the goal is progress, not perfection. Additionally, reading a well-chosen book on the topic helps develop the psychology behind the invisible engine: your mind.

Recovery and next steps

Post-race recovery tips

Crossing the finish line is a huge achievement, but recovery begins immediately. Drink fluids, eat a balanced mix of carbs and protein, and stay active gently to prevent stiffness. In the days that follow, take at least a week off from structured training. Light swimming, yoga, or walking helps circulation. Listen to your body, and do not rush back too quickly.

Motivation for your next event

For most, the first 70.3 is the gateway to a lifelong love of endurance sport. Some aim to improve their time at the same distance, while others look towards a full IRONMAN. Whatever your choice, **remember to celebrate your success before moving on to the next goal. ** The journey of training and racing is just as rewarding as the destination at the finish line.

Half-Ironman Checklist: Quick Summary

You're now familiar with the guide on preparing for your first 70.3. Here's a simplified checklist to help keep your training on track.

✅ Set your goal: Commit to finishing strong, whether your focus is completion or a personal best.

✅ Follow phases: Build gradually through Base → Build → Taper.

✅ Swim prep: Practise endurance sets, open-water sessions, and sighting skills.

✅ Bike focus: Prioritise long rides, practice nutrition, and improve your pacing.

✅ Run smart: Do brick sessions, long runs, and practise running off the bike.

✅ Strength & mobility: Add 1-2 short sessions weekly for core and injury prevention.

✅ Nutrition: Train your gut with 60-90g carbs per hour, test gels and hydration.

✅ Gear ready: Wetsuit, goggles, road or tri bike, run shoes, and transition kit.

✅ Mental strategy: Break the race into sections and practice staying calm and focused.

✅ Recovery: Schedule rest days, stretch, and plan time off afterwards.

Once you’ve conquered the Half IRONMAN, take the next step with our Full IRONMAN training guide.