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Home / Training / Long distance / Conquer Ironman: Part 1

Conquer Ironman: Part 1

In the first of this two-part series tri coach Joe Friel shows you how to plan and build your training in prep for an Ironman

Preparing for an Ironman triathlon is a daunting task. The training rivals that of any endurance sport but none are more challenging. Besides the training there are also sophisticated equipment needs, exacting nutritional demands and extreme mental discipline. It’s much like planning a space mission: you can’t leave anything to chance.

This is the first of a two-part series on how to prepare for an Ironman event, whether it’s your first or your 10th. Part one is concerned with the physical training. Next month’s part two will address equipment selection, race nutrition, mental discipline and unique situations.

All the information presented here is based on what I’ve learned from preparing athletes for Ironman events over the last 20-plus years. Some athletes aim to be competitive while others simply want get to the finish line smiling from ear to ear. Either way, the strategies are similar and have been race proven. So let’s get started.

The basics

Once you’ve decided to do an Ironman, you have to know what your goal is. Is it to simply finish? If this is your first Ironman, finishing is a worthy goal. Even when I’ve coached pro triathletes for their first Ironman this has been the primary goal. More experienced and competitive Ironman athletes usually focus on a finishing time goal,?often a personal best (PB) . Either of these goals is attainable if you train appropriately.

The key to Ironman training is not, as most athletes think, how many hours or kilometres you put in weekly, but rather how long and race-like your workouts are in the last 12 weeks before the event. While weekly volume is, at best, a secondary performance predictor, there’s no doubt that it will be more than if you were training for an Olympic-distance race.

So how many hours should you train? Given the need for frequent long workouts in each sport, the weekly volume will typically end up being at least 12hrs and is generally well over 20 for top age-groupers. Pros will train 30hrs and more, but then that’s their job. You, on the other hand, have a life away from pools, roads, trails and tracks, so you’ll need to make sure every minute spent training counts. You can’t afford to waste any training time and one way to make the best use of it is to organize your training using periodisation.

Periodised training was covered in depth in November’s 220 [The Ultimate Training Plan –?Ed] but here’s a quick recap of the periods in the order they should occur:

Preparation 2-4 weeks devoted to gradually getting back into a focused routine of generalized exercise.

Base 9-12 weeks of training primarily aimed at improving endurance, force (strength) and skills.

Build 8-9 weeks of training specifically for the unique demands of your A-priority race.

Peak 1-2 weeks of tapering workout duration to allow for more rest while maintaining workout intensity to stay sharp.

Race The week of your A-priority event where rest and mental focus is critical.

Transition 1-6 weeks following the A-race when your mind and body are allowed to recover from the stress of the previous months.

Base training

This article primarily focuses on the ‘build’ period since that is when the heart of your Ironman training takes place. In the ‘base’ period, training involves gradually lengthening workout durations in all three sports coupled with short sessions focused on the skills required for swimming, cycling and running.

Don’t underestimate the importance of skill work. Most triathletes could improve their race performances by 5-10% simply by becoming more skilled. Weight training should reach a peak early in the base period with the emphasis decreasing thereafter as hill work is introduced. By the time you start the build period, your general fitness should be good but you certainly aren’t Ironman-ready.

Build training

The following are the keys to getting the most out of your limited training time for each sport in the build weeks:

Swim Ironman first-timers must work only on two primary abilities: swimming skills and endurance. A swim instructor will be a big help with the first. The weaker your skills, the more often you should swim, but at least three times a week is a good target to aim for. To build your endurance, gradually increase your longest weekly swim workout to 4,000m three weeks before the race and get in at least two swims in open water.

The competitive Ironman athletes, whose skills and endurance are already well honed, should concentrate on muscular endurance in the final 12 weeks. This involves long sets (300-500m) done just below anaerobic threshold with 20-30sec recoveries between intervals.

Bike The bike leg generally makes up almost half of your total race time. So for most athletes, regardless of ability or experience, this is where close to half your training time should be spent.

Interestingly, research has shown there’s a fitness ‘carry over’ from the bike to the run. In other words, training on the bike will improve your running, though the reverse is not as likely. The bike is typically the key to how well you finish. And the hillier the course in your intended race, the more important the bike leg becomes to your overall performance.

Athletes focused on simply finishing an Ironman should get in lots of saddle time in the last 12 weeks. Aim for at least four weekly rides including a long ride that gradually builds to about 6hrs. Two or three of these steady, moderate-effort, 6hr rides (with the last coming three weeks before the race) will build both physical and mental fitness. Besides rehearsing your race-day nutrition, work on refining your bike position, your pedalling skills and staying aerodynamic for long periods of time.

Competitive Ironman triathletes should have already built their longest ride to the 5-6hr range before coming into the final 12-week build period. Now the emphasis is on building the muscular endurance to race fast, with a weekly long ride of about 4-5hrs employed to enhance race-specific fitness.

The first 3-5 of these are tempo intervals to increase power. Warm up for 30-60mins and then do 4-6 intervals of 20mins each with heart rate in zone 3 (8-16 beats per min below your anaerobic threshold heart rate). Or, if you have a power meter, ride at 80-85% of your functional threshold power. Recover for 10mins between intervals. Cool down for 30-60mins and you’re done.

Once you’ve completed several weeks of tempo intervals, it’s time to up the ante with 4-6 long aerobic threshold rides. The effects of these sessions are threefold, preparing you mentally and physically for the demands of racing, and also to act as a benchmark effort to gauge your progress. (See the Test your training box on page 61 for further benchmark efforts.) Here’s the protocol… Warm up for 30mins and then ride steadily for 3-4hrs in the upper half of your zone 2 heart rate (17-23 beats per min below your anaerobic threshold heart rate). If you have a power meter, ride at 65-75% of your functional threshold power. Cool down for 30mins. Be sure to eat and drink exactly as you plan to in the race.

These workouts mimic your race intensity, so failing to maintain the goal pace for 4hrs here means you won’t be able to do it for a longer time come the race. If you are struggling to hold form, reduce your target heart rate or power until you have it dialled in for 4hrs. The last such ride should occur three weeks before race day.

Run Training for the run leg of an Ironman is the most problematic of the three sports. If you’re going to get injured in training, running is the likely culprit. The most probable run workout to injure you is the long run – this means that you have to be smart when running long.

The keys to injury prevention are proper shoes, a flat footstrike (not on your heels or toes), forgiving running surfaces, a gradual progression of duration, limiting the duration of the long run and doing the long run only when your legs are relatively fresh.

This last point is critical. Many Ironman athletes do their long run the day after a long bike ride, believing that it will simulate the tired legs they’ll experience on race day. This is a mistake that greatly increases the risk of injury. The day after a long ride, your legs are experiencing chronic fatigue, whereas on race day they’re suffering from acute fatigue. They’re different states.

If possible, separate your long run from your long ride by several days so chronic fatigue isn’t an issue. Your risk of injury will decrease significantly and the quality of both workouts will increase. If they must be back to back on the weekend due to time constraints during the week, do your long run on Saturday and your long ride on Sunday.

Your longest run need not exceed 3hrs, no matter how long you expect it to take in the race. And there’s a good reason why. Every run workout has a risk-reward ratio. As the duration increases from a few minutes to an hour, both risk (of injury) and reward (fitness benefits) increase gradually with reward leading the way. At around 2hrs, the reward curve begins to plateau and eventually tips downward – reward is decreasing. The risk curve also becomes slightly steeper around the 2hr mark as danger increases. By 3hrs the fitness reward is low and the injury risk is high. That’s the time to stop.

As with the bike, Ironman first-timers should simply focus on building skill and endurance with a long run every other week in the last 12 weeks. Skip one week in every three to make sure your legs are recovering. Rest assured that the long bike ride will also boost your running.

Mix running with walking on these long workouts just as you will on race day. Use the long run to figure out and refine the best refuelling strategy. By the last of these long runs (about 4 weeks before the race) you should have your refuelling strategy sorted

Experienced Ironman athletes should also do a long run every other week, with the longest being no more than 3hrs. This duration should have already been established during the base period. Now the run emphasis, as with the bike, changes to building race-specific muscular endurance.

The key workout for competitive Ironman athletes during the final 12 weeks is the aerobic threshold run. Within a 2.5-3hr run, after warming-up, include a 1hr portion that’s done steadily in the upper half of your zone 2 heart rate (15-20 beats per min below your anaerobic threshold heart rate). Add 10-20mins to this aerobic threshold portion every week until you’re running 2hrs at this effort within your long run. This is your Ironman goal pace. The pace you’re running should remain rock steady for the entire time. If it doesn’t, you need to lower your target heart rate or pacing strategy. Refuel and rehydrate just as you plan to in the race.

Bricks, weights and stretching

Besides your swim, bike and run work, additional brick sessions, weights and stretching will complement your training during the build period.

Bricks Every time you finish a long bike ride, immediately go for a 20-30min run at goal race effort. If possible, ride for an hour with the last 30mins at Ironman effort before your long runs. Both these workouts will help prepare you for the ‘rubber legs’ experience of running off the bike.

The most important brick workout is what I call the ‘Big Day’. There are two of these in the final 12 weeks – at the ends of the fifth and eighth weeks prior to your race. Each of these workouts should be followed by five days of active recovery.

The ‘Big Day’ is a dress rehearsal. Start by having your planned pre-race breakfast at the same time you’ll have it on race day. Later do a 1hr swim rehearsing your race-pacing strategy. An open-water swim is perfect, but don’t do it alone.

Rest for 90mins and eat after the swim, then start a 5hr bike ride. Competitive Ironman athletes should include a 4hr aerobic threshold portion, as described previously.

After the ride, eat a light meal immediately and rest for another 90mins. Finish the day with a 2hr run including an aerobic threshold portion if you’re a competitive Ironman racer. Refuel and rehydrate using your race strategy throughout the day.

You’ll learn a lot about how prepared you are for your race and where you need to focus your training with these two ‘Big Days’. Make adjustments to your training accordingly in the following weeks.

Weights The heart of your strength training should be completed during the base period. All you need to do in the build phase is maintain the strength gains you’ve made. One workout each week will accomplish that. Monday is usually best for a weights session for most athletes. This should be a short workout that focuses on the sports’ five primary movement and stabilizing exercises with only two sets of each, one light and one heavy. If you haven’t been lifting weights before, don’t start now. It’ll create muscle soreness and detract from your swimming, cycling and running workouts since your muscles won’t be adapted to the stress.

Stretching The repetitive movements associated with triathlon training cause reduced flexibility in your joints, especially the hips, shoulders and ankles. This is because the same movements are done, for hours at a time, through a limited range of motion. Allowing this tightness to progress unattended contributes to the risk of injury over time.

Working on increasing the range of motion in these joints will go a long way in helping to prevent soft-tissue damage and may also improve your performance. A little stretching done daily is better than a lot of stretching done infrequently. A few minutes before and after workouts, and first thing morning and last thing at night, will do wonders for your suppleness over time.

Peak and race training

Start your taper three weeks before your Ironman race. A taper involves reducing the duration of your workouts every three days to allow for more rest and recovery.

To maintain a high level of fitness, do a mini-race simulation brick every third day involving all three sports and alternating the emphasis between the bike and run. Each brick should be shorter than the previous one. The two days between these simulations are for active recovery. By following such a plan, you’ll complete four or five of these bricks with each shorter, but no less intense, than the preceding one.

Only do two short workouts on most days in the week of the race, each including 3-5 90sec intervals at the highest effort you anticipate using in the race, with 3min recoveries. Two days before the race is a good time for a day off. The day before the race do your shortest swim, bike and run workouts of the week but include some peak Ironman-intensity efforts. That’s it for the training but there’s far more to a successful Ironman than training. There’s still the equipment, nutrition and race plan to take into account. And that’s what you’ve got to look forward to in the second part, coming to the website soon.

Joe Friel has coached elite and age-group triathletes since the ’80s

Profile image of Matt Baird Matt Baird Editor of Cycling Plus magazine


Matt is a regular contributor to 220 Triathlon, having joined the magazine in 2008. He’s raced everything from super-sprint to Ironman, duathlons and off-road triathlons, and can regularly be seen on the roads and trails around Bristol. Matt is the author of Triathlon! from Aurum Press and is now the editor of Cycling Plus magazine.