How Do You Succeed at Kona?

Heat, humidity, wind, pacing—we take a look at some of the factors that affect success at the Ironman World Championship in Kona.

how to succeed at Kona?
Kailua-Kona, Hawaii: Athletes swim in Kailua Bay ahead of the Ironman World Championship.

It’s almost that time again—the most exciting time of the year in the Ironman world: Kona! The Ironman World Championship is due to take place on the Big Island next Thursday, October 6, and Saturday, October 8. For the first time in the event’s history the race will take place over two days, with the women racing on Thursday and the men on Saturday. 

Kona is a notoriously difficult event that involves a 2.4-mile swim, a 112-mile bike, followed by a marathon. It’s the most famous event on the Ironman circuit and has a kudos and prestige unlike any other. And it’s not just the 140.6 miles that athletes cover on race day that makes this race so legendary, there’s plenty more to factor in. Whether it’s the heat haze that drifts over the tarmac as athletes run into the infamous Energy Lab, the unabated winds blowing over the barren lava fields, or the never-ending humidity that makes you feel like you’re stepping into a steam room every time you leave your condo, one thing’s for sure: Kona is a beast of a race. 

With that in mind, we’ve taken a look at some of the factors that can stand between competitors and the finish line at one of the most iconic and challenging events in the endurance sports.

How do you succeed at the Ironman World Championship? 

Over the past 15 years that I’ve been focusing my coaching practice on Ironman athletes, I’ve been fortunate to witness more than 100 age groupers take on the challenge that is the Ironman World Championship. Many mistakes were made and many lessons have been learned along the way. In my experience, the biggest things that stand in the way of success in Kona fall into five key categories:

  1. Heat/humidity
  2. Wind/aerodynamics
  3. Nutrition
  4. Pacing
  5. Mental/emotional energy

1. Heat and humidity

Without question, one of the most common mistakes I see athletes make is not adequately preparing for the heat and humidity of Kona. This manifests in all kinds of ways (cramps, premature depletion, heat stroke) that generally amount to walking a large portion of the marathon. 

The environment of the Big Island is so unique that it is very tough to prepare for, it’s that feeling of a wet blanket that envelopes you as you step off the plane on the Kona tarmac. Nevertheless, in order to race successfully in this environment, every effort must be made to properly acclimate. In my experience, the three most important factors for dealing with the heat and humidity in Kona are:

a) Conducting some heat acclimation in the weeks leading in

b) Having an appropriate heat management strategy on the day

c) Recognizing that even if properly acclimated and with an appropriate heat management strategy, you will still be slower than you would be on a cool course. 

Let’s dive into each a little deeper…

How to succeed at Kona: Heat acclimation

The ability to dissipate heat is an important attribute that must be trained. Studies have shown performance improvements in hot environments in the range of 7-10% following a brief acclimation period (e.g., Tyler et al., 2016). This can amount to an hour or more over the course of an Ironman. Fortunately, heat tolerance is a quality that is quick and easy to train. In fact, sometimes “training it” does not even have to involve training. For example, Scoon et al., (2007) found that just a daily 30-minute sauna post-exercise for 10-14 days resulted in an increase in time to exhaustion in the heat of 32%. These improvements have since been replicated with other passive measures such as taking a hot bath immediately after training. 

Personally, with my athletes, I like to use a mix of exercise heat and passive heat, shooting for 60-90 minutes a day (combined) in the 10-14 days leading in. On the exercise side of things, elevating the core temperature to a desirable level is relatively easy to do simply by adding some periods of “no fan” trainer work. At moderate-high power outputs, it really doesn’t take anything more aggressive than this.  

How to succeed at Kona: Have a heat management strategy

Overheating is quite a binary phenomenon, your body is either able to dissipate the heat you’re creating, or it isn’t! For longer, low-intensity races like Ironman, many athletes never exceed this heat dissipation threshold and are able to keep a high output for the duration of the race with ‘traditional’ strategies. In Kona, this is not the case. 

It’s not so much the heat of Kona that is problematic, although with the unobstructed sun beating down on you on the Queen K, you may disagree. But beyond the heat, the humidity is the biggest factor that sends many athletes’ races astray.

Under normal circumstances, our bodies do a fabulous job of dissipating a substantial portion of the heat that we produce through evaporation of sweat. However, as our soggy shoes can attest, evaporation just does not happen in a humid environment like Hawai’i.

For this reason, other heat management strategies become more important. Obviously, hydration is important to keep up with all the sweat that we are dripping onto the pavement, but beyond this, ice—on as many points of contact as you can manage—is an athlete’s best friend in Kona. Some athletes that I’ve worked with have, very successfully, gone to the extreme of sewing mesh pockets onto the inside of their race kit so that they could have a built-in ice “air conditioner” throughout the run. 

How to succeed at Kona: Recognize you will be slower

This is, without doubt, the most common mistake: an athlete goes 9 hours in a cooler race like Ironman Brazil or Ironman Arizona and expects to pull off a similar time in Kona. Even at similar fitness, you will still be significantly slower on the Big Island—everybody is! If you fight the island on this, you are in for a long day! So how much slower?

In the words of three-time Kona champion Jan Frodeno

“You have to come here at your very best game, prepared as well as you can be, and then pretend to race at altitude. You’ve just got to be willing to give an extra 10-20% to the conditions.”

Jan Frodeno, three-time IRonman World champion

This 10-20% completely gels with what I have seen from athletes who are able to put together a good race in Kona. Several years ago, I took five years of data from my team to look at how their Kona power and pace numbers at race heart rate compared to their “home” numbers and the average drop off of 16% was right in the middle of the ballpark given by Frodeno. This was greater on the run (~20%) and less on the bike (~13%). Of course, this varied depending on how acclimated the athlete was, the size of the athlete, where their “home” was (i.e., the conditions they’re used to training in), but the most crucial point here is that in Kona, everyone is slower.

2. Wind/Aerodynamics

Photo courtesy Kenny Withrow

Another common mistake is not adequately preparing for the windy conditions in Kona. The winds on the Big Island can be brutal, and if you are not used to riding in them, they can be stressful and, frankly, demoralizing. 

There are two trends right now in bike training for triathlon that can be very problematic when the athlete touches down on the Big Island: 

  1. Bike positions are becoming increasingly aggressive, making positions less comfortable and bike handling more of a challenge.
  2. With the advent of Zwift and other virtual training platforms, triathletes are spending a lot more of their cycling time indoors (where there are no 60mph wind gusts to learn to deal with!)

When you throw these two factors into a very crowded bike course with a lot of people of similar ability, it can lead to an incredibly stressful 112 miles. 

The thing about stress is it’s energy sapping, and the Ironman World Championship in Kona is one particular venue where you certainly need all of the energy that you can get. 

It is very common for athletes who are successful in other environments to really struggle when it comes to this particular race. A part of this, as we have mentioned, is the heat, but, in addition to this, there is not likely to be a more exciting and stressful race on the athlete’s calendar. A large part of this stress can be attributed to a competitive, crowded, windy bike. 

So if you want to succeed in Kona, do not spend all of your training time leading into the race on the trainer. You’ve got to get out there and ride outdoors, ideally in some challenging, windy, hot, and potentially rainy conditions. You need to get extremely comfortable riding in the aero position in all conditions. Do not spend all of your time sitting up in training and expect to be cool, calm, and collected in the aero bars as crosswinds try to push you into oncoming traffic come race day. 

The above is not to discount the importance of an aerodynamic position to a fast, efficient bike split. However, at the wind speeds that are typical on the Big Island, the greatest aerodynamic advantage that you can find doesn’t come from having your pads an extra 10mm closer or bringing your front end 5mm lower. No, the biggest advantage, by far, comes from making sure that you are comfortable riding with others in the windiest sections of the race and that you don’t have your nose in the wind, i.e., that you have the company of a legal draft. 

A very typical situation in the race is that it is calm for the first half of the bike and then the winds begin to pick up as the turn is made in Hawi (around the halfway point of the bike course). Coming down off that descent, with the extra little adrenaline that comes from a few unpredictable gusts, can make it seem like a wonderful time to “make your move.” Invariably, the athlete regrets this decision as they get back on the Queen K and they find themselves alone as the wind becomes their new greatest rival. In my experience, the athletes who perform well in Kona are very crafty in ensuring they always have people (legally) around them for the toughest, windiest parts of the bike, even if it means pulling back a little on their desired output on the bike and saving more of it for the run.   

3. Nutrition

how to succeed at kona with nutrition
Photo courtesy Shutterstock

Hot races are simply different when it comes to nutrition. Sticking with nutrition that has worked for an athlete in cooler races is often a mistake in Kona. So, why is it different? What are the key considerations when it comes to your hot race nutrition plan?

First and foremost, let’s return to the impact of stress, both heat stress and race stress. When the system is under stress, less blood is sent to the gut. This is obviously not ideal, as our ability to fuel a superior performance is entirely dependent on our gut working at 100% capacity to absorb essential carbohydrate and fluid. So, challenging as it may be, the first part of a solid nutritional plan, especially in Kona, is to relax and stay as calm as possible. This clearly relates directly to the previous point of taking the time in training to become extremely comfortable on your machine. 

OK, so we have achieved Zen master status, what’s next? The concentration of your sports mix is especially important in a hot race. In normal situations, our body has some fluid in “reserve” that it can use to aid the digestion of our nutrition. In a cooler race, an athlete may be able to get away with a slightly higher sports drink concentration or throwing in a mix of semi-solids/gels. If the concentration is too high when it arrives in the gut to be transported across the gut wall, the body simply pulls some fluid into the mix to assist. However, in a hot Ironman, that precious fluid is in short supply. So, help your gut out! Give it sufficient fluid to keep the overall carb concentration to a low to moderate level. Depending on the mix, 6% is a good solid starting point, providing ~90g of carbs in 2 x 700ml bottles per hour.  

RELATED: Sports Nutrition Pathway

While speaking of body reserves, another reserve that your body keeps “in case of emergencies” is an electrolyte reserve. Under normal circumstances, many athletes find they do not need to take in any electrolyte supplement in addition to what their sports drink provides. This is because, although the electrolyte output in sweat is significantly greater than the electrolyte input in sports drink (lick your arm during the race and compare the taste to a swig of sports drink for evidence), the shortfall can be made up by your body’s sodium, chloride, and potassium reserves. However, these reserves are finite and, as we have established, we’re sweating these out at all kinds of crazy volumes in the Kona conditions. When the stores run dry, it can lead to all kinds of “race mistakes.” These mistakes can vary from persistent muscle cramps through the back half of the run (not pleasant!) all the way up to the life-threatening problem of ‘fluid intoxication’ (hyponatremia). This is why it’s all the more important to have a well-defined electrolyte plan as part of your nutrition plan and to test it well, under high sweat conditions, before the race. On the low end, this may amount to a heat-specific hydration formula that offers 400 mg/hour of sodium. For “salty sweaters” it may amount to additional supplementing to 1000mg/hr or more. Either way, it is an important additional consideration when it comes to your nutrition and hydration plan in a depleting environment such as Kona.

4. Pacing

Without question, more pacing mistakes are made at Kona than any other race on the circuit. There are several reasons for this, but the two biggest ones:

  1. It is likely hotter than all your other races
  2. Everyone around you is faster than other races

I think we have established by now that, due to the heat, Kona will be slower than your other races and that the smart athlete adjusts their pacing plan down 10-20% to account for this, so let’s move onto the second factor—everyone around you is fast!

In analyzing the difference in pacing between those who have a successful race in Kona versus those who do not, the number one part of the course that makes the difference is over-pacing the first five to 30 miles of the bike.  

A few years ago, I compared Frodeno’s pacing strategy versus the typical age grouper’s strategy. Of course, as we’d expect, Frodeno was quicker throughout, but the biggest difference, the place where he really distanced himself from the rest of the field, was in miles 127-136 of the race, i.e., miles 13-22 of the marathon, the Energy Lab, and the return trip along the Queen K. He was going a phenomenal 35% faster than the typical age-grouper in this section, compared to the first 10-30 miles of the bike, in which he was going only 15% faster than the average age-grouper. A significant number of age groupers were actually going faster than Frodeno through these opening miles of the race! (And we can probably guess how their races turned out…)

Needless to say, the vast majority of athletes over-pace the first 30 miles of the bike (through to Waikaloa). I think the primary reason for this, as I alluded above, is that everyone around you is fast, so there is a definite tendency to get dragged along at higher-than-optimal outputs. This is exacerbated by the fact that so many athletes get out of the swim together and the roads are crowded, so there is a real push to hold your position. These mental tendencies to “keep up” early come back to bite the majority of athletes later in the race. If there is ever a race to hold back for the end, it is Kona. The race just gets progressively harder through the entire day and not just in the way that any Ironman gets harder, but the course itself just builds to a leg-crushing, soul-crushing crescendo…

On the bike, the cooler temperatures and the calmer conditions, coupled with the shelter of a larger pack in the first half of the bike, give way to heat, blustering cross/headwinds, and much more solo time with your nose in the wind on the way home. Throw in a few nasty little pitches that are much more gradual on the way out and you have the makings for a long return journey if early pacing errors are made. The run is no better…

The little bit of breeze coming off the water and the fired-up crowds along Ali’i Drive in the early miles are replaced by hills, heat, and a whole lot of demoralizing solo time alone with your own regretful thoughts for those who pace the bike and early run too aggressively. 

5. Mental/Emotional Energy

There is simply no race that compares to Kona when it comes to the pre-race buzz that abounds on every corner of Kona town. This is the biggest race around, attended by the absolute best, most tri-obsessed athletes on the planet and this becomes so readily apparent the minute that you disembark the plane at Kona’s unique open-air airport. The otherwise sleepy town becomes this Mecca for serious triathletes the world over. Every part of the town reminds you of this. Everywhere you look are uber-lean specimens, engaging in nervous training all over the island, seemingly resolved to make you question and doubt your own preparation. Add in the various equipment manufacturers lining Ali’i Drive, making you doubt if you can even keep up if you do not have the latest wetsuit and the latest ride of your favorite sponsored athlete.

Needless to say, there is this perpetual energy and buzz to the island that is both taxing and, at the same time, very hard to ignore. Maybe one of the best aspects of strolling Ali’i Drive in race week, especially for those athletes coming from places around the world where triathlon is a fringe sport, is that feeling of being among “your people.” But, always keep in mind, this time out in the Kona sun among “your people” can also be incredibly taxing. I have known more than one athlete who got lured in by the pre-race excitement to the point that they showed up on race day completely flat. 

RELATED: How to Manage Competition Stress

And to add some further context to this, let’s consider the toll of travel too. Hawai’i is literally in the middle of nowhere, so almost everyone who flies there is coming from a long way away and crossing multiple time zones. This alone is incredibly stressful on the body and, in an ideal world, would be accompanied with a lengthy period of adaptation, but Kona is expensive and many of us have jobs. For most of us, it’s logistically challenging to spend as long as needed in Kona pre-race to be perfectly prepared. When athletes get there, they are immediately confronted with the excitement of everything around them and so, when they should be laying in their air-conditioned condo resting, they’re out and about in the heat soaking it all in. Tired athlete, out and about all day, feeling the pressure to squeeze in the final training often amounts to a tired athlete rocking up to their most important, most challenging race of the year. 

And it is not just the competition that challenges our energy resources, in the words of six-time Kona champion Mark Allen: 

“A key thing was learning how to feel at home on the Big Island of Hawaii. It is a very intense place with a unique and strong energy or power about it that can be very intimidating if you do not just embrace it and work with it.”

MARK Allen, six-time ironman world champion

The race takes place in one of the most challenging, most naturally powerful places on the planet and the environment alone will tax your energy to the limit. It is absolutely crucial to not spend too much of that energy before the cannon fires.


It is not an exaggeration to say that Kona is one of the toughest races in the world to put a good race together. I have known very fit athletes who have spent a decade or more trying to figure out the intricate mysteries of the Big Island, managing to qualify and show up year after year only to be faced with another disappointing race. On the other side of the coin, I have known first-timers who have managed to avoid these mistakes by showing up to the island with a little healthy fear and a respect for the extra challenges that racing in Kona brings. This typically involves some, or all, of the following:

  • An awareness of the energy-sapping hype that race week in Kona town entails
  • A smart pacing plan that acknowledges the building difficulty of the Ironman World Championship course
  • A well-planned, well-tested nutrition, hydration, and electrolyte plan that is appropriate for the extra challenges that the lava fields bring
  • A comfortable, well-practiced (outdoors!), aerodynamic position
  •  A deep respect and humility for the tough, hot, humid, environmental conditions the athlete will face and a willingness to adapt their race plan accordingly  

Making it to Kona for the biggest race in the Ironman world is such a tremendous accomplishment that one should never take for granted. Capping it off with the satisfaction that comes with executing a high-quality race in one of the toughest environments on the planet offers a measure of satisfaction that is exceedingly rare, but certainly not impossible.