Ironman training: 5 common weaknesses and how to overcome them

Each discipline of long-distance triathlon presents unique challenges that must be defeated. Here are the most common problems… and how to resolve them


What’s standing between you and achieving your race goals? What does that race distance require to do well? And are these requirements the same as your weaknesses? If yes, then these race-specific weaknesses are what I call ‘limiters’. Here are the ones that I’ve found to be iron-distance specific and what you can do to overcome them…


1. Time to train

Typically, Ironman age-group athletes train between 12 and 24hrs each week. Thankfully, you can finish an Ironman, with a smile on your face, training at the low end of this range. But the faster your goal race time and the more competitive you want to be, the more training time it takes. That’s a given.

So what can you do if you don’t have endless available time to train due to career, family and other responsibilities? Since the bike is the key to Ironman success, be sure to ride a lot in the last 12 weeks before the race. About half of your training should be on the bike. You can cut back a bit on the swim and run, as long as you focus training on what’ll give you the greatest return on investment. And, of course, you’ll need to adjust your race goal to match your reduced training volume.

2. Swim skills

The most common limiter for the swim at any triathlon distance is skill. And the longer the swim leg of a race, the more important this becomes. With the 3.8km Ironman swim, mastering skill is critical so that you don’t expend too much energy.

Seek out a good swim instructor who can refine your technique. You’ll enjoy a much greater return on your investment by doing this, rather than following endless intervals in the pool with poor technique.

You also need to understand that the technique used in open water is not the same as that used in a pool – Ironman swimming requires a much more aggressive style. Watch any video clip of the pros in an Ironman swim and you won’t see any of them with picture-perfect form. It’s all about length and grabbing an arm full of water. Find a swim instructor who knows what an Ironman swim is all about, start weekly lessons now and make that the key focus of your swim training.

 3. Bike endurance

As mentioned previously, the 180km bike is the most important portion of the Ironman race. If biking is your
greatest limiter, then you need to shift more time to it and away from the swim or run – whichever is your strongest sport.

On the bike, the most common limiter is muscular endurance. This is the ability to hold a relatively high effort for a long time, which means training in zones two and three (both aerobic) as this is the range of effort at which you’ll be riding.

The triathlete’s complete guide to heart rate zone training

You’ll need to undertake a weekly long ride at these intensities, alternating between zone two for 20mins and zone three for 10mins, building from about two to four hours over several weeks. This will boost your muscular endurance in the last 12 weeks before the race. With a long warm-up and cool down, this ride may become five hours or longer.

The most proficient way to do this ride – and the race – is by using a power meter to manage pace and a heart rate monitor to prevent excessive effort (above zone four) on hills.

4. Run endurance

The run in an Ironman-distance race is slow. The problem is that darned 180km bike ride that comes before
it, which makes fatigue your limiter on the marathon.

So what’s the most effective preparation to cope with that fatigue? The most important factor is to become so fit on the bike that you can afford the time to hold back slightly. This is very hard to learn, but I guarantee that if you let others pass you in the first 40km, you’ll finish feeling ready to run faster than usual (you’re also less likely to have
stomach problems). What’s even better is that later in the race you’ll inevitably pass those who passed you, probably on the run while they’re walking.

So all you need to do in training for the run is to build endurance. In the last 12 weeks before the race, commit to a weekly 60-90min bike ride that includes many zone three intervals followed by a 2:30hr run at a comfortable effort.

5. Race-day nutrition

Product manufacturers try to convince us that during a race we need to pack our guts with protein, sodium, potassium, magnesium, calcium, vitamins and the rest. But experience and sport science tells me that we don’t need most of it. It may be great for their bottom line but it’s not good for your race.

What you need most are carbohydrates and water, and I like to separate these into two unique sources. If both come out of the same bottle, you’re likely to digest too much or too little of one while trying to follow a schedule for the other. Instead, carry whatever carb source you prefer, such as gels, blocks and bars, and eat them to a schedule that meets your calorific needs. Also, carry water and pick it up at aid stations when you’re thirsty.

How to avoid a DNF in Ironman: essential race day strategies


There’s no secret to improving your iron-distance performance. Follow these sound principles, be consistent with your training and you’ll achieve your ambitions come race day.

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