Ironman: how to train for a PB

Iron-distance racing may be debilitating but, at its heart, the training principles are simple. Iron legend Mark Kleanthous reveals his top 10 tips for racing faster and reaching your goals …


Always remember: if you want to improve your performance in a long-distance race, it’s thinking smarter and tailoring your workouts that will do it… not just punishing your body with ever-tougher sessions. With that in mind, here are my top 10 tips for a faster Ironman or long-distance race gleaned from racing over 30 of them. All of them will save you time on race day – and only one will cost you any money. 


Note that these tips are aimed primarily at experienced long-course triathletes who want to improve their times. But if you’re a beginner, there’s no harm in starting as you mean to go on. All it takes is a few simple changes for you to boost your performance.


You only have a few chances to be at your peak during a season. By adding lots of racing to your training schedule, you will not produce a quicker Ironman time. When training for ‘long’, racing pushes you over the edge and compromises your performance on race day. Your mind needs to be fully fresh to focus throughout the Ironman – not feeling like this is just another race.

You lose consistency of training leading up to, and recovering from, races which are not at Ironman pace. Running races, for example, bear no relevance to iron-distance as you’ll be running at a quicker pace.

A middle-distance triathlon race should be done six to eight weeks before your long race as this is more race-specific than another long ride or run. You must evaluate your middle-distance performance because it will still give you time to make any final adjustments in your training if required.

A good session is to complete a controlled, high-tempo workout or brick (swim to bike, or bike to run), working with someone of similar ability. During the last six to eight weeks, you need race-specific speed to go faster so it has to be at Ironman pace, not quicker. Ironman winners never race much in their build-up.


Group cycling is alien to the bike segment in long-distance because of its non-drafting nature. Remove the social element, and know when to train with others and when to train on your own.

In group cycling, you’re going at someone else’s pace – typically that of the strongest rider – and you’re never going to go that quick on your own. Group riding is simply eating up the miles, and you get lulled into a false sense of security by covering a distance that you’d normally find difficult on your own. Group riding also has too many distractions: you’re not listening to your body because you’re busy concentrating on the wheel in front. This is why you must do solo riding to make you mentally tough.


On race morning, you need to take on board at least 1,100 calories to cater for your metabolism’s normal day as well as for the start of the race.

Age-group Ironman athletes often encounter problems about 8-9hrs into the race, when they start to slow down. Sound familiar? This happens because the body is very low on energy, not having fuelled right before the race. This is hard enough to do in training, and nerves on race morning can make it even more of a challenge, but you must learn to do this to improve.

By simply eating a slow energy-release carbohydrate breakfast, such as oats or oatbran porridge, or muesli, will maintain your energy levels for longer and should see you move up the results table as others struggle to keep going. This may seem obvious but is often the most over-looked final piece in the Ironman jigsaw puzzle.


All you know is what you do. A good, experienced long-distance coach will identify what you need to add and what you need to eliminate from your current training, in order to gain those all-important extra minutes. Having someone with knowledge to provide analysis and evaluate your training responses is key. Plus, being accountable to someone else is a great motivator.


Allow time to taper properly: a taper period of four (not two!) weeks is a must. As your body adapts over time to endure a bigger volume of training base, your taper must reflect this.

Exposing your body to cope with more training stress will require much more recovery time in order to reap the rewards, namely a quicker time on race day. Triathletes whose times never show any year-on-year improvement are usually guilty of too short a taper. With a two-week taper, you will still be tired come race day: 14 days doesn’t give you the time to recover sufficiently to go quicker.

Reduce volume but still train at Ironman race pace during your taper. This will keep you fit and get you chomping at the bit… which will undoubtedly prepare you for your fastest Ironman ever!


During Ironman training your long runs should never exceed 18 miles, as it can take as many as 14-28 days to recover. Long runs during Ironman training expose you to injury and overtraining far more than they would do marathon runners due to the huge build-up of fatigue. Leg strength is needed for both the bike and the Ironman marathon, and long runs reduce this strength dramatically.

Triathletes who’ve never run a marathon aren’t clouded with the long-distance training mentality. They often have little knowledge of how many 20-mile runs they need, which can work to their advantage as they often run to their potential.

A marathon runner completes many long runs in order to build up endurance, whereas an Ironman athlete is continually building endurance through daily multiple sessions and long bike rides – so the frequent long runs simply
aren’t needed.


Don’t be fit to train – be fit to race! You only have to look at your training speeds and compare them to your Ironman split speeds: these will show that you’re going far too hard in your sessions. It’s easy to get preoccupied with speed, speed and more speed! Why? Because you think this makes you go quicker. Well, it doesn’t. No-one has 100% VO2 max so you need to improve what you have and develop your energy systems for long distance.

Continually going hard does not, and will not, improve long-distance endurance. Remember: Ironman is not about proving you’re tough, it’s about being a smart athlete. And smart triathletes make few mistakes.


You should do your longest endurance session no closer than 10 weeks before your target race. Undertaking a last mega-session of cycling and/or running within the last six to eight weeks may be tempting, but you won’t recover in time. And it’s not specific to going quicker.

The wrong timing of this session will reduce your endurance – not develop it – because you won’t be giving your body enough time to compensate. By race day you’ll have depleted your energy levels and won’t be fully prepared mentally.


If you want to go quicker in the Ironman, get rid of the float/pull buoy. It’s no coincidence that the best swimmers can still go on and pedal well. Because they know how to use their legs.

Saving your legs for the bike and marathon was necessary in the early days, but now we have great flotation devices called wetsuits. And the fitter your swim legs are, the easier you’ll be able to switch to cycling. Modern triathletes seem to ignore kicking to the extreme, preferring to use a float all the time… no wonder they can’t run to their bikes when they hit terra firma!


Progression to going quicker is not just about ‘more and harder’. This will increase your endurance in the short term but for Ironman performance it won’t help you go quicker. The obvious and easy option is to just keep adding more effort and speed, on the grounds that as you get fitter you can cope with more. But this alone will not make
you go faster.


The key to real progression is a combination of the following: putting enough time aside to recover; maintaining the pace for longer; completing race-specific sessions within the last six weeks; and improving your nutrition. Do all this and that new PB is waiting for you…

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