10 things often overlooked when starting an Ironman training plan

10 things often overlooked when starting an Ironman training plan

You’ve nailed the sprint, conquered the Olympic distance race and even got a 70.3 under your belt. Now you’re thinking about taking on the big daddy of triathlon, the Ironman.

But before you tackle that 2.4-mile swim, 112-mile cycle and cheeky marathon finisher, there are a few things you need to consider. Do you have enough time to train, do you want to spend money on a coach, how are you going to fuel, and are you willing to make the sacrifices required to reach your goal?

Triathlete runner tying his shoe laces

Here are 10 important questions to ask yourself if you’re considering a tilt at the ultimate swim, bike and run.

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1. Are you fit enough to go long distance?

If you’re willing to put in the training there’s nothing to stop you completing an Ironman triathlon but don’t be fooled, going the distance is tough, particularly if you don’t already have a solid fitness base. This is not a race you enter three weeks before race day after a discussion in the pub and hope it’ll all be fine.

Most experts suggest having at least two years’ experience of triathlon racing before you consider entering, with at least one Olympic-distance triathlon under your belt. If you haven’t done a triathlon yet, ideally you’ll be a strong and capable swimmer, a decent runner and cyclist and you should definitely factor in a few shorter practice triathlon races in your training.

Athlete swimming in Ironman triathlon competition

Of course you can still complete an Ironman even if you’re starting from a slightly shaky fitness base but give yourself longer to prepare and bear in mind that most courses have cut off times between 16 and 17 hours and you want to be confident you can meet them.

2. Are you willing to make sacrifices?

An Ironman triathlon is a blooming long way – 140.6 miles to be precise. You’re not going to get around it after a few park runs, a summer in the resort pool and the odd Sunday bimble on the bike, training will take up a lot of your time.

Many plans recommend training six days a week, often twice a day, and the longer runs and rides will take up a good proportion of your weekend too – not to mention the all-encompassing tiredness that prevents you doing anything but lying on the sofa afterwards.

Female athlete training in daylight for Ironman triathlon competition

There will be 5.30am starts, missed social occasions, less time to spend with family and friends (and the arguments that may entail), even meeting work commitments can become tricky. So before you start training, you need to ask yourself honestly: are you willing to make those sacrifices to meet your goal?

3. Do you want a three-month, six-month or 12-month training plan?

If you’re new to the Ironman distance, a good training schedule is worth its weight in gold. It’ll break your training time down into manageable chunks so you know what you should be doing and when. A structured approach will ensure you up your mileage safely, give you ideas for speed and strength training, feature a balanced spread of all disciplines, and make the whole thing seem less overwhelming.

Person writing triathlon training plan

With so many plans out there though, choosing one can be tricky. The most important thing you need to ask yourself is how much time you’ve got before your race and how many weeks of training do you want to put in and go from there.

  • Three-month Ironman training plans

If you’re an experienced triathlete who’s already in good racing shape, then a 12-week or 16-week plan is a good choice. It gives you plenty of time to knuckle down to some race-specific training but remains short enough to limit the risks of physical or mental burn out.

  • Six-month Ironman training plans

Most triathletes train for around six months in the lead up to an Ironman triathlon; this is a solid amount of time to prepare for the distance and the challenges ahead, provided you have a good fitness base to build on.

  • 12-month Ironman training plans

For those new to triathlon, prone to injury or getting back into the sport after a long break, a 12-month plan is a smart option. Longer plans allow you to build fitness slowly and safely before tackling more intense sessions. This puts less stress on your body, reducing the chance of injury. There’s also plenty of time to recover from any setbacks, such as illnesses or training blips along the way.

4. Do you want to splash out on professional support?

Hiring coaches used to be the preserve of professional athletes but now many amateur triathletes employ expert support – around 75% according to Ironman – whether that be remote coaching online, in-person coaching or purchasing a personalised training plan.

Coaches tailor training to your specific needs, strengths and weaknesses, they’ll work sessions around your schedule and they’re a wealth of training advice and motivation. It may seem like a costly luxury but it really will help you get to that finish line – and anyway just think of all the money you’re saving not going to the pub.

Two coaches training a female cyclist indoors

If hiring a coach for your whole training block isn’t a consideration, you might want to think about a couple of expert sessions to set you on the right track. A professional bike fit will ensure you’re comfortable and cycling efficiently as you start to rack up those miles while getting your technique checked by a swim coach will highlight any weaknesses to work on, helping you make a few tweaks for a more powerful stroke.

5. Are you able to train consistently?

Ask any triathlon coach and they’ll say one of the most important aspects of training is consistency. Regular, consistent training helps your body adapt to the workload, progress steadily and is the best way to get results. Missing the odd workout here and there is generally unavoidable but skipping multiple sessions one week then going for high mileage and intense sessions the next just sets you up for injury and burn out.

To ensure you’re able to train consistently you’ll need to commit to sessions and schedule them in your diary. If you know you have a number of events or engagements coming up – such as school holidays, summer of weddings and work travel – you might want to choose a race at a time when you have fewer commitments.

6. Have you worked out how you’re going to fuel your race?

With the winners of World Championship Ironman races crossing the line in around eight hours and most mere mortals adding a few hours on top, it’s fair to say you’re going to be moving for a very long time. In order to replace lost calories and provide your body with the energy it requires to finish, you’ll need to think seriously about fuelling and ensure you practice your strategy before race day.

Nutritional needs vary from person to person depending on a number of things such as body weight, the time you’ll take to complete the course and genetic factors. Generally though, the bike is the best place to refuel and set yourself up for a good run.

back and white image of cyclist training on-road

Triathlete magazine suggests drinking water or hydration drinks for the first 15 minutes on the bike leg to let your body adjust to cycling and then aim to take on 250-400 calories every hour, switching to liquids only around 20-30 minutes towards the end of the cycle so your stomach doesn’t feel too full when you start running. During the run they advise reducing the calories by around one third, so 170-270 calories.

The nutrition you choose is up to you, but to help you identify what might work for you, we produced a more detailed guide to the best sources of carbs for cycling and what to eat compete. Just ensure you practice in training to see what your body responds best to. Some people like to use a combination of solid food, gels and hydration drinks to keep the calories topped up.

When it comes to taking on solid food on the bike, bars such as the Classico, Avanti and Zenzero each provide up to 45g carbs per bar and are totally delicious - providing a huge boon to your motivation as well as giving you the nutrients you need for endurance.

Veloforte Performance Pack 


7. Are you ready to up the tempo?

While the Ironman is an endurance event where you’ll mainly be working in the aerobic zone, mixing up your training with speed, tempo and threshold sessions, alongside longer steady-state workouts can have great benefits. Upping the intensity not only keeps things fresh and interesting, it also has a knock-on effect on your overall pace too, meaning you’re able to go faster with less effort.

Athlete running in the rain on-road

Try adding a few miles at tempo pace to the end of your long cycle and run, or upping the intensity towards the end of a long swim. Putting in the effort when you’re already tired will stand you in good stead for race conditions.

You can also play around with intervals. Try these sessions recommended by 220 Triathlon:


Start with: 3 x 200m at Ironman race pace, 20 seconds rest

Next: 6 x 100m at a vigorous pace, 15 seconds rest

Then: 3 x 200m at Ironman race pace, 20 seconds rest

Finish with: 12 x 50m sprint, 10 seconds rest


3 x 15 minutes at Ironman race pace; 2 mins at 2kph faster than race pace; 3 minutes recovery


5 x 1.5km at Ironman race pace; 500m at 30 seconds per km faster than race pace; 500m at recovery pace

8. Are you ready to work on your weaknesses?

Everyone has a favourite triathlon discipline and it’s easy to favour those sessions above the others. But all those hours in the saddle won’t make your swim any stronger. If you have a weaker discipline make sure you put the work in and focus on improving, even when you really, really don’t want to.

For example, one particularly motivated triathlete we know well deliberately wakes himself at 4am on random days and forces himself to go and run around Richmond Park pulling a tyre... to his mind, this is all to help train himself to do the things he doesn’t want to do! Maybe a bit extreme but you see where we’re going.

9. Have you scoped out the course?

Take some time to study the route maps of your target race. Knowing what you’ll be up against on race day means you can adapt your training to be better prepared for the race you’ll actually face. If it’s a sea swim, make sure you get some sessions in on the coast, if the bike course is hilly get those hill reps in and if the run's on trail, ensure you do some of your workouts off road.

If you have time it’s a good idea to get to the race location a couple of days early so you can get a bit of practice in on the course too.

Two athlete runners racing to the finish line

10. Are you happy to walk?

Even the most experienced age groupers have been known to throw in a few walking breaks rather than running the full marathon distance. Walking some of the final leg can save vital energy on hills, help you digest better at fuel stations and a run/walk strategy will get you to the finish line quicker than going all out then bonking at mile 15 (here’s some handy advice on how to avoid the bonk by the way) and having to walk the last 11.2 miles. During your long runs throw in a few walking intervals such as 1 minute walk/9 mins run to practice fast walking and simulate race day.


If these 10 considerations have not put you off and you're still here reading, then now is the time to come up with a plan to make your aspiration a reality. Read our guide on how to structure your own triathlon plan and you're off to a good start!