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Game Changer Part 4 Race day nutrition for Maximizing endurance performance.

Recently I did a video, talking about how I have changed my idea of nutrition over the last decade. In this Blog I’m just going to focus on race day nutrition and performance. Most of the research in Australia is about what we can do to put the maximum amount of Carbohydrates in our body. This was me 4 years ago and I truly believed it was the best and only way to race as I thought it was giving me my best results. I never had any of the potential problems that a lot of athletes had, such as GI distress, Vomiting and Diarrhoea, that end so many people's day.

Now lets talk a little bit about the science of nutrition and performance. Everyone has seen the nutrition companies adverts, stating that someone gained anywhere from 5 % up to as high as 18 % improvement from taking their high sugar concentration blend. Most of these tests are done over 20 -60 min intense efforts and based on an improvement of output of speed or power. This sound great, so why wouldn’t everyone want to consume these products.

Lets think about the facts and see if this really makes any sense what so ever. Our body is able to carry Muscle Glycogen (carbohydrate) which depending on our size can store 2000 to 2500 calories. Everyone knows from looking at their Garmin that at intense output our body burns around 1000-1200 calories. So saying that, if our Muscle Glycogen levels are full or even half full we have enough Carbohydrate in our body to sustain this 20min to 60 min max effort. So there really can only be 2 conclusions if the people are really getting these gains, - it’s a sugar high response in the brain like when someone takes a drug. A bit like when a parent says their kids have gone crazy when they have sugar, its not a reaction to the extra carbohydrate in the lollies it’s a sugar high in the brain. Alternately, maybe a refined concentrate form of carbohydrate is easier and faster for the body to absorb. Which could also make sense, as I’m not a scientist.

Back in 2014 at IM cairns what my nutrition looked likee

Conclusion 1 if it is really just the sugar high and not the actual Carbohydrate giving us the improvement in output, how long does the hit last and how much do we need to consume to get the hit. There has been a research document published showing the same improvement from a controlled group of athlete who just swished the high sugar concentration drink and spat it out compared to those that consumed the recommended dose. If this is the case maybe like any other addictive things we consume ie. Alcohol, Caffeine, if we actually consume less the bigger effect it will actually have on us. So maybe we are training our self to be reliant on it to be able to perform rather than get a performance advantage from it.

Conclusion 2 If high sugar concentration formula is easier for the body to absorb, how long is our body going to last on these resources. So the maximum our body can adsorb is around 280-340 calories an hour and we are burning between 1000-1200 depending on our size and that’s if you mix glucose with fructose. Our body is lazy and if you're fuelling your body with the fastest easiest source it can use, then that is what it will use first. So on average, you are going to have a 700 calorie deficit every hour as you can't intake as fast as the body is burning. So basically if we are relying on carbohydrate you do the maths any event over 4 hours we are going to have no muscle glycogen left. So you will totally be relying high sugar concentration formula and if we are not feeling GI stress and can still consume the maximum amount of around 300 calories an hour we are only going to be able to provide the muscles with 30% of their energy needs. Most people feel this at about the 5-10km mark of a 70.3 when their pace instantly slows by about 30 sec a km and their legs feel like led. We call this bonking and when you think about it, it actually makes sense. The problem is, no research for performance is ever done for more than a 2 hour period so they never actually come to this conclusion as their not allowed to put someone on a treadmill for 9 hour, and to be fair who would want to.

Now comes the Light bulb moment, are we doing it all wrong especially for an event that is 4 hours plus in duration. What if we could actually train our body to use its natural physiological system, and burn a combination of all it fuels. That all calories are not the same, there is fat calories and carbohydrate calories. Although we only have around 2400 calories of Muscle Glycogen, even the leanest of athletes has 50,000 calories of fat . If we can train our body to burn some Fat for fuel throughout the race, rather than once its bonked and has gone into survival mode, because there isn't anything else left to burn. Not only that, but if conclusion 1 is correct and it’s the sugar high giving us the extra energy boost, it does seem counter productive that we would be doing that at the start of the race when we are feeling good and potentially the bigger problem for most athletes is actually over pacing rather than at the end when we want to push on. If conclusion 2 is correct, rather than giving it high sugar concentration formula which switches our body instantly to burning pure carbohydrate, which we know, it we can't possibly keep topped up. We use real food that our metabolism needs to digest and work a little harder to turn to fuel maybe we could burn more fat in the process and keep our muscle Glycogen store for longer and potentially never bonk. You might say I can't eat when I'm exercising, but really at the early parts of an 70.3, IM or Ultra event if your heart rate is too high at the start to digest food I would say pacing is your problem.

What my nutrition fueling more looks like these days

For the first 5 years of my athletic journey, I was the maximum carbohydrate intake man and argued black and blue it was the best way. I had good results, and you can do it, but the risk is greater, and for over 50% of the people out there that end up with upset stomach, there is another way, and I would argue you will go faster and your energy levels will be better. Lets just do the same Maths as before, but this time our body is burning 50% fat and 50% carbs which over a long endurance event, if we have trained our body just to use real food should be easily achievable, and up to 80% has been proven in the Faster study recently published. So instead of burning 1000 calories Carbohydrates an hour we only burn 500, then we add around 200 gram with real food, we all of a sudden have enough energy to last hours, plus then add in some gels at specific stages as a pickup, with the sugar high, and you unlock a huge new potential to go for nearly double the time without bonking.

Here is 2 different 70.3 and a IM races I did 12 months apart 1 on the maximum amount I could consume, around 4 gels an hour to using real food and around 1 gel every 2 hours . Cairns IM and 70.3 which I did have good days and took out first place at the IM and 2nd at 70.3. Then Busso IM and Shep challenge which yes you will say is different course but look at the power profile and bike split for each comparison. Then look at the run splits that followed for each and you tell me which is performance enhancing. More importantly than performance enhancing which is a healthier option for longevity in the sport?

First Comparison is Busso IM 2015 to Cairns IM 2014

Busso IM Bike 2015

Busselton IM 2015 (real food)

Bike Avg watts 243 time 4:46:29

Bike Nutrition 4 bars 2 gel

Run 3:04 steady pace ran last 10 km strong

1 bar 2 gels

Busso IM 2015 run

Cairn IM bike 2014

Cairns Im 2014 (Max Liquid nutrition)

Bike Avg watts 247 time 4:48

Bike Nutrition 20 gels

Run 3:15 and go down hill fast from the start legs dead by 15 km

Run Nutrition

10 gels plus Lots of Coke back half

Cairns IM run 2014

2nd Comparison Cairns 70.3 2015 to Challenge Shep 2015

Once again exact same trend Bike Power / Split virtually identical except the race done on real food, the pace doesn't drop off on the run.

Challenge Shep Bike

Challenge Shep

Real Food Race

Negative run split felt amazing

Challenge Shep Run

Cairns 70.3 Bike

Cairn 70.3 2015

Max Liquid Nutrition

Run split went downhill real fast and legs felt terrible

Cairns 70.3 Run


Well what does this all mean ? Well Im not telling everyone to never take on any liquid nutrition. As there is benefits in taking some as in electrolytes. Maybe instead of thinking what is the maximum we can put down our mouths, rather, what is the minimum I need to perform to my full potential. This is no scientific peer reviewed fact but is 2 real world case scenario's where we can conclude using real food was at least as good if not better.

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