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The myth of cardio

Part 1 of things you should know about your sport but are not told!

Starting off with the big buzz word of this age.., Cardio!

Let's begin our conversation by asking the Cambridge dictionary for clear clarification:

'physical exercise that increases the rate at which your heart rate works'

The internet is swamped with short videos of either a female Paris Hilton or a male bodybuilder with a good tan as the front guys. They espouse the now buzz of cardio; 20 minute cardio, 15 minute cardio, and the daddy of them all 10 minute cardio! Now before all the dyed-in-the-wool triathletes stop reading, take my tip - DON'T! This is for you! Very few triathlon articles concentrate on what is the 'real' basis of our races or distances. Here at we use this description as the bedrock of our training systems.

This note is for triathlons of all distance - sprint, olympic, half and full iron distance, and we will start by using science to explain. In the top level of swimming an 800m race is viewed as a distance event. All research confirms that a race time of between 8 to 9 minutes is made up of

  • 3% to 5% creatine phosphate delivery

  • 10% to 15% anaerobic system

  • 80% aerobic, thus 'cardio'

How does this relate to us, the triathlete? Well, our super sprint race takes 30 minutes. Our sprint race takes 1 hour. Olympic distance takes about 2 hours give or take. My point is that if a 10 minute event is 80% aerobic then what is our shortest race distance, the super sprint that is 3 times this duration? Thus training should be based on the predominant assumption that our races are aerobic. Now, before you say 'we do three different disciplines', I ask you 'how many hearts do you use in the race'? After the initial burst of the first 200m of the swim, the heart must sustain 'the cardio' for at least another 28 minutes at a sustainable rate that can only be described as aerobic. Again before you say 'but at the start of the bike and run it must be anaerobic' - this is not so. The speed of each is controlled by the blood lactate levels. Permit me again to generalise, the zone of the onset of lactate is around 4 millimoles. After a 10 minute swim it will be below this level if you're a very fit well trained athlete. For the skeptics that say 'then how come when I watch a race we see all these exhausted dudes sprinting like maniacs at the end of the race? By your accounts that is not possible!' I will agree, however this final 100m hero is fueled by creatine phosphate that we described earlier in the swim 800m breakdown. Creatine phosphate is produced inside the cell automatically no matter how tired you are aerobically. So let's go back and address the 10 minute cardio. We will again use the documented science that is agreed and not in question. Aerobic function needs to be a minimum of 40 minutes of work. No one of any substance argues with this. I point out a 40 minute interval session is not 40 minutes of work. So if one wants to do an aerobic piece of work in an interval capacity, say 40 seconds on, 20 seconds of rest, then that session requires a minimum 60 minutes to provide positive aerobic stimuli. Thus everybody's head explodes when I blog that 95% of all triathlon participants don't have any aerobic training in swimming at all! So on race day, we are all fired up, feeling fresh as we are used to short simple main sets with lots of fluff -

  • The warm up

  • The kick set

  • The stroke drills

  • The different strokes

all jammed in to a 45 minute to 60 minute training session.

Sorry about telling you the truth! I won't get as many internet hits as the 10 minute cardio gurus, because they are telling you what you want to hear, playing loose with the actual facts of what your body needs. Let me just add this 'Can I break it up into 2 or 3 pieces that add up to the 40 minutes of work, and so I did the work?' The answer is a big NO! Conclusion I want you to understand that most of your triathlon races are over, completely over by 500m into the swim. Yes I know you finish, but the performance level is so under what you could achieve with proper adoption of what 'cardio' really is. Just the way Trisutto coaches see it!

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