Ironman Fueling gone Awry

Ironman Fueling gone Awry

This photo was posted recently on a tri-forum; it depicts a carefully planned eating orgy which makes creative use of a bicycle as the banquet table.

According to the forum thread, the author of said orgy is an IM-bound competitor who has set up her bike for a practice training ride with the calculated fuel requirements for her event – wow!

  • Bike weight 17 pounds
  • Bike + fuel 30 pounds (29.9 pounds if skewers are titanium)


Oh my… Indeed, the multi-sport world’s athletes and plethora of coaches have a habit of working themselves into a state of indigestion when it comes to the subject of fueling and nutrition for endurance events.

Calorie tally:

  • 5.5 water bottles – estimate 300 calories each of some stomach-clogging carbo sports drink: 1650 calories
  • 15 gels – estimate 125 calories each: 1875 calories
  • At least 2 powerbars – 240 calories each: 480 calories

That’s about 4000 calories, just from what we can see. It looks like the bento box is full as well, so our gut-busting tally could easily be more!

…and people wonder why so many IM race reports read of nausea, bloated stomachs, gas, indigestion, vomiting.

M2 Common Sense IM Fueling Observations:

The ideas outlined here are based on twenty years of experience and experimentation beyond the narrow confines of convention.


  • The majority of nutritional meltdowns in triathlon are caused by athletes eating and drinking too much, not too little.
  • Ingesting large and frequent amounts of fuel is unnatural, and all the more when you factor in vigorous exercise in what are often difficult weather conditions.
  • Regurgitated textbook training dogma is rather illogical – train slow because this supposedly teaches your body to burn fat, and all the while ingest large and frequent amounts of carbohydrate, hmm.

It would seem apparent that the above training scenario is more likely to accomplish the following:

  1. Train the athlete to be slow.
  2. Create unnecessary fuel dependency.
  3. Complicate race day where fuel requirements will be even greater.
  • It is not advisable to attempt to replace all the calories you expect to burn, nor should the athlete be fixated on somehow not losing weight in a training/race session by cramming down excessive fuel.
    Read all the race reports that describe “things were going great until I started puking at mile 40 of the bike.”
  • Triathletes further overcomplicate their fueling thesis with exotic drinks and food concoctions and timing of such – and still so many races gone awry because of “nutritional issues.” Fueling does not have to be as complicated as the tri-world is wont to do.
  • Optimal fueling is that amount (not more) which allows you to maintain a steady energy flow, and this most often involves much fewer calories than suggested by boilerplate tri-dogma.
  • Your body can be trained to be more efficient in its use of existing fuel stores by following these very simple steps:
    • Drink only water or fluid replacement drink during the first hour of ride. As you gain experience, you can extend the period of time before you take in gels or bars.
    • Drink fluid replacement drink and eat a gel or piece of bar every 30-45min thereafter.
    • Avoid bonking – increase amount of fueling frequency if bonk symptoms become apparent – very simple.
  • In addition to making you more fuel efficient, optimal fueling will provide you with a much keener sense of how much fuel you really need (or don’t) than by simply cramming down gels/bars/whatever to meet artificial calorie counts.

M2 Personal Fueling Anecdotes / Observations:

  • I have won Ironman races finishing strong on as little fuel as 1.5 bananas and fluid replacement drinks, nutritionally impossible the calorie counters would insist.
  • Although my races were generally 8.5 hours and thus less than most competitors, my intensity factor was much higher than the average competitor, thus suggesting a much higher calorie and carbohydrate burn rate and the need to have fueled more.
  • When fit, steady-state challenging terrain 100mile+ rides can be completed using only a couple of gels, or at times just my fluid replacement drink.
  • I vary how much I eat in training to better understand my needs.
  • Despite the seemingly sparse fueling in these rides, I do not get off the bike famished or particularly hungry.
  • Although I am not a big believer in brick runs after long bikes, on those occasions where I do choose to run, lack of energy due to fueling inadequacy is not an issue.
    When evaluating M2 fueling concepts, consider that I supposedly break every rule when it comes to fueling and its consequences:

    • I favor higher intensity training which supposedly does not teach my body to burn fat, but instead a finite carbohydrate fuel supply and where I should thus bonk – but I don’t.
    • I replace calories sparingly which should further make me bonk – but I don’t.
    • I should get off the bike depleted and famished – this is not the case.
  • By reducing the inherent systemic stress of having to ingest and process large and frequent amounts of fuel, I similarly reduced a major race variable while directing blood and body energy away from the digestive system to the legs and arms and raced much more effectively.
  • My training supplement budget is virtually nil.


The ideas I present certainly run counter to the general tri-culture where too often there can be no excess. However, M2 optimal fueling is supported by Ironman Championship performances and strong performances by athletes of every ability who do not feel that fueling has to become a complicated 4th event.

Clearly, one can teach the body to become more efficient in its use of existing and additive fuel stores, thus relieving in large degree the systemic stress of having to assimilate extraordinary fueling in the midst of an already grueling event.
Optimal Fueling will make you much more aware of your body and its needs, and as such is a powerful knowledge tool that can be applied to your training and racing.

In summary, the athlete that fails to make fueling efficiency a premium consideration in his training, will forever fall short of his endurance potential. Teaching the body to use fuel more efficiently should be something every endurance athlete should practice.

Smart Training by M2

For a related article on fueling, see the article Fueling for Life – amazing even to me!

%d bloggers like this: