Nutrition and 4+ hrs rides

[jcza]

I use Hammer Perpeteum, water and real food on 4 hr rides+

 

Also check out Allen Lim's recipes for race fuel that some PROs often use.

Real lekka stuff.

 

I avoid gels and excessively sweet things to avoid the energy spikes. Might use it for the final hour cos I love jelly babies.

 

You're right to use Hammer Dale but the spikes are a myth

 

The Myth of the “Insulin or Sugar Crash” during exercise…

 

There is an idea out there that people need to consume “slow burning” sugar (or carbohydrate) during exercise or else your body will experience a “sugar crash” and you will die… (ok that last part is not really what people think)…but if nothing else, your race will be sabotaged by “quick burning”, “insulin spiking” types of sugar.

 

I want to tell you all that this IS NOT TRUE and, in fact, THE OPPOSITE IS TRUE about what you should eat during exercise!!!

 

First, I want to define the difference between a “simple” and “fast” vs. “complex” and “slow” sugar. “Simple” and “fast” do not mean the same thing. Simple means that the sugar is a monosaccharide or disaccharide - ok what the hell does that mean? It means that the sugar is made of one or two units of something. For instance, fructose is just one block of fructose and glucose is just one block of glucose. Sucrose is a disaccharide (or made up of 2 units of something). Sucrose is made up of a block of glucose and a block of fructose stuck together. According to the National Institute of health, a “complex” sugar is one that is made up of at least three “blocks” of something. (http://www.nlm.nih.gov/medlineplus/ency/article/002469.htm)

 

Maltodextrin is by definition a “complex” carbohydrate because it is a polymer and made up of many “blocks” of glucose pieces stuck together (In turn, starch is a bunch of maltodextrin pieces stuck together and is also, obviously, complex) Here is why I have to define these terms though - Maltodextrin is a COMPLEX carbohydrate that acts like a “FAST BURNING” sugar…ok that is just crazy but it is true…

 

So I obviously have to prove it. How quickly a sugar “burns” or is digested, absorbed and has an effect on your bloodsugar is described through the glycemic index (the higher the score, the more quickly the sugar is digested, absorbed and affects blood sugar). This index is subject to a lot of influencing factors, including whether or not you are consuming fat, protein and fiber with your carbohydrates- but putting that aside and just looking at the sugars- we get an idea of how quickly these sugars act. Here is a very rough (but hopefully ball park accurate list - it is tough to get this information because the glycemic index is almost always represented in real foods for practical reasons):

 

Glucose 85-111

Maltodextrin 105

Honey 32-87

Sucrose 58-65

Lactose 46

Fructose 12-25

 

So you see now that maltrodextrin is a “complex” sugar that “burns fast” and fructose is a “simple” sugar that burns “slow” (However there are other problems with fructose in the way it is processed in the body that go beyond the scope of this article that don’t really make it glycemic index friendly in large quantities - but this is a separate issue).

 

So getting back to what to consume during exercise.

 

During rest, you can experience a “spike” in blood sugar and a subsequent rise in insulin that causes a “crash” or mild hypoglycemia (low blood sugar) a bit later. This is true, DURING REST.

 

BUT…this is NOT TRUE when you are exercising or racing!!!! This is the myth that a lot of people carry around that is insane in the membrane. We have evolved (if you believe in that type of thing) to fight tigers and ligers and dinosaurs (right?) and that is why we have historically exercised. To do this our body produces an adrenaline response when we exercise, similar to a “fight or flight” response. When we exercise today our body thinks we need to fight something or hunt something so it is smart and increases our heart rate for the battle, shuts down our digestive system and shunts blood to muscles, adjusts our pupils so we can see better – and lots of other stuff too - but it also decreases insulin production out of our pancreases so we have consistently high bloodsugar levels for the battle with the dinosaur. And this is why you will not have an “insulin crash” during exercise!!! (this is also why you need to worry about sparing your glycogen stores during exercise - because that glycogen is getting broken down to keep blood sugar up but that is a separate discussion for another article as well)

 

So why does this matter - it matters because sugars that are higher on the glycemic index typically absorb quicker than those lower on the index. Gastric emptying times (how fast the sugar gets out of your stomach) are shorter. And this matters A LOT during moderate to hard exercise. Remember how I said when you are fighting the dinosaur that your body shunts blood from your digestive system to your muscles for the battle?? That is also what happens when you exercise. So gastric emptying is a BIG DEAL!! It is an even bigger deal if you are racing or exercising hard - I am sure everyone who reads this has experienced that truth in all its vomiting glory at one point in their lives during a hard interval or race. Think of the burger stops at the races and the number of riders you see vomiting after eating a burger.

 

Therefore, high glycemic sugar is where it is at for exercising and immediately after exercising (for quick absorption recovery purposes- beyond the scope of this discussion). Hammer Nutrition is super researchy with their products and they have found that maltodextrin has the fastest gastric emptying time. Hammer gels use maltodextrin almost exclusively (a little fruit juice too) as their carbohydrate source – most nutrition companies do not use maltodextrin at this time because it is a more expensive ingredient to use than alternative sugar sources.

 

Conventional wisdom is currently that one should eat low glycemic index foods during rest and prior to exercise and high glycemic (preferably maltodextrin for during) during and immediately following exercise.

 

Now if someone tells you to eat whole wheat bread or some crazy sh#t like that during exercise to avoid the “sugar crash” you can call BS on them and know exactly why they are whack….

[deonkretch]

Lots of scientists on theHub

 

My 2c - works for me.

 

Longer than 3 hrs - 2 bottles of Cadence Marathon + 1 Bottle of Rehidrat (learnt this on Epic from one of the medics - the most underrated 'juice' to chuck into a bottle - I always keep some Rehidrat with me).

 

I also have difficulty eating on the bike, have tried Powerbars, Enerjellies and find that the baby potatoes from Woolies with Aromat works a treat.

 

However - A friend uses ENSURE - yip the ou-tannie-milkshakes, mixed to a thick milkshake consistency in one of those really small bottles that runners use. Have a big swig of this every 45minutes or so and you're fine to go!

 

But, if you're one of the lucky guys to ride the Cape Pioneer this year you'll get perfectly tender ostrich fillet sosaties at the waterpoints... damn those things beat a GU or gel hands-down!

[Wyatt Earp]

Spikes a myth ?

As this article says it's not, there are many that will say it's fact.

 

In the end of the day, it's all about understanding your own body.

80% or perhaps even more cyclists don't.

 

@Deon, yes the Rehidrate is superb and I agree very underrated.

[davetapson]

Apparently under conditions of exercise they body uses a different biochemical pathway than the typical 'eat carbs, get raised blood glucose, get shot of insulin, get depressed blood glucose' cycle (spikes).

 

It's called something like the Glutame-4 cycle. Google it, and if you find a laymans version, explain it to me.

 

But what it means is:

1. that you don't get spikes,

2. it doesn't matter what type of sugar you use (slow or fast release) as you won't get the spikes from the fast release anyway.

 

A comment passed by one of the sports docs at Potch was 'you may as well use game - at least it's cheap.'

 

Prior to doing LCHF I found granola bars excellent - a quarter of a bar every half hour or so, otherwise bananas which are natures gu and a whole lot more palatable.

 

Post LCHF it seems that you don't need much refueling, and when you do, anything will do. I just take whatever is at the seconding tables.

 

Cadence Marathon / EPIC Pro were my drinks of choice and pretty much could carry me through a 5hr+ day.

Edited October 1, 2013 by davetapson

[KaKa]

Very interesting reading. However how does the ur physical condition influence how ur body reacts. I noticed many say they ride on water, game ect…

Will the effects be the same for someone that is not conditioned? Vs someone who is very fit.

 

does the level of conditioning not play a big part in the choice of nutrition?

[TopFuel]

Pretty much the way I understand it all, but where do you tap from when you go anaerobic ?

My question regarding this, and brining this in to the discussion is because whether we like it or not, that is the ONLY zone the majority of people know.

 

They don't ride sensibly, start of in the anaerobic zone, feel flat, recover a little and go straight back to doing it again.

They ride till they can go no more.

Then one has to hear "I was right up there, but not sure what went wrong" "I must be eating wrong" "maybe I did not carbo load enough" "I just had a bad day" and many more.

 

Thus I said the body needs to be trained, nothing was said about being "fat primed"

I still think that if you have a lower body fat percentage, you might stand a greater risk of running near empty if your on the bike nutrition is not enough.

 

As I said, too much anaerobic riders out there, not feeding the muscle enough oxygen , and I used the term "they are a hunk and chunk of lactic acid"

 

But here is what I would like to know and needs explained to me, when you go anaerobic, and you have depleted the muscles, stripped the body from the necessary oxygen it needs, where does one then try and tap the energy from ?

 

Okay, going anaerobic has nothing to do with the amount of muscle/liver glycogen storage. Aanerobic respiration is related to the exertion that you put your body under. You pretty much have it explained already: don't go out too fast or you'll ruin yourself. Anaerobic respiration is a type of energy creation process (and by energy I mean ATP - the cellular energy source), comparable to aerobic respiration which requires the same substrates (and oxygen), to produce ATP in a much more effective way.

 

Think of it as a car, if you drive sedately, you'll get 6L/100km or whatever. If you put the pedal to the floor, you'll get 22L/100km or whatever. Same energy source, but the conversion process is much more efficient in aerobic (sedately) vs anaerobic (hammer time).

 

I agree with you that people don't know how to train effectively, and believe that hard, all-day-every-day is the way to go. Hell, I did before I started university and was exposed to proper human physiology and the ability to critically read a research article.

 

What needs to be emphasised is that anaerobic respiration is not a process that can continue for extended periods of time. Usain Bolt uses almost 100% anaerboic respiration, for a max of probably 20-30s (I dont think he could go at that speed for much longer than that).

 

What people tend to do is ride above their anaerobic threshold/lactate threshold, which as has been described is an inefficient, non-sustainable process. But it is not the only process occurring. Respiration (at a cellular level) is a balance of aerobic and anaerobic. At exertion levels below the lactate threshold, the dominant force is aerobic respiration (the engine that lets you ride 200km at 60% exertion), as you get further above the lactate threshold to maximum intensity, the balance between aerobic and anaerobic respiration shifts toward anaerobic. In the Usain Bolt example, he is probably going at 5/95% ratio. Most of us, when pushing on a climb/end of a race @80-90% max are at a ratio of 60/40 (thumbsucked values, but the concept is what I'm trying to illustrate). And that 40% is what ends a ride. It uses up way too much fuel, it creates unwanted byproducts. The 60% is still chugging along at its efficient pace.

 

If I'm coming across correctly, that is why if you go too hard in the first 30-60mins of the race, you completely deplete your glycogen stores and "bonk"/"hit the wall" etc... I agree the body needs to be trained, and the fat primed comment was not aimed at you at all. Training increases your body's efficiency (hence a hard day of intervals will raise the lactate threshold and your VO2max), which will shift the relationship toward aerobic metabolism at higher intensities.

 

 

Carbo loading is only useful if your glycogen stores are depleted from exercise.

 

FOR most of us weekend warriors, our glycogen stores aren't depleted before a race because we didn't train the day or 2 before a race AND most people's normal diets contain enough carbs.

 

Nope, carboloading hypersaturates your glycogen stores. Glycogen depletion is what happens when you bonk/hit the wall, and you body cannot adequately mobilise fuel to match your requirements, thus your performance drops substantially.

 

Carboloading for a weekend warrior is effective and has been proven in multiple studies. In trained athletes it is more effective, as their bodies are more efficient at using fuel, but the process of hypersaturating your glycogen stores is just as effective.

[Cyclewizz]

 

does the level of conditioning not play a big part in the choice of nutrition?

 

IMO - yes but I'm no scientist.

[MTBc]

I normally use 1 GU and it's usually about 40min - 1h before the end. Nothing worse than running out of energy 5km from the end. takes a lekker ride and makes it feel KUK. (if spikes are a myth, then I must be a unicorn).

 

Usually eat bananas, little bit of biltong and/or some cashews and a peanut butter sarmie on longer rides and drink water with a 50/50 mix of coke+water for sugar boost if needed.

[TopFuel]

Apparently under conditions of exercise they body uses a different biochemical pathway than the typical 'eat carbs, get raised blood glucose, get shot of insulin, get depressed blood glucose' cycle (spikes).

 

It's called something like the Glutame-4 cycle. Google it, and if you find a laymans version, explain it to me.

 

But what it means is:

1. that you don't get spikes,

2. it doesn't matter what type of sugar you use (slow or fast release) as you won't get the spikes from the fast release anyway.

 

A comment passed by one of the sports docs at Potch was 'you may as well use game - at least it's cheap.'

 

Prior to doing LCHF I found granola bars excellent - a quarter of a bar every half hour or so, otherwise bananas which are natures gu and a whole lot more palatable.

 

Post LCHF it seems that you don't need much refueling, and when you do, anything will do. I just take whatever is at the seconding tables.

 

Cadence Marathon / EPIC Pro were my drinks of choice and pretty much could carry me through a 5hr+ day.

 

That doesn't really make much sense. Here's the cliff notes energy production pathway:

Aerobic:

Glucose (via glycolysis)-> Pyruvate

Pyruvate (in cells) -> Acetyl-CoA and CO2

Acetyl-CoA (via Krebs cycle) -> NADH

NADH (via oxidative phosphorylation) -> 45ATP (with oxygen as final acceptor)

 

Anaerobic:

Glucose (via glycolysis) -> Pyruvate

Pyruvate (via NADH) -> 2ATP + lactate + CO2

 

Summary:

Aerobic: 1 glucose -> 45ATP

Anaerobic: 1 glucose -> 2ATP + CO2 + lactate

 

Secondly, an insulin spike rise during exercise makes even less sense. You need blood sugar levels to be raise for energy requirements, yet insulin is going to drop those levels. Plus, exercise is a pro-sympathetic state, which causes release of adrenaline and noradrenaline, both of which are anti-insulin hormones.

 

Your ultimate conclusion is correct, but the reasons are not. You wont get spikes because insulin is not dumped into your blood stream in response to high blood sugar. Additionally, the pro-sypmathetic state means that glycogen will be mobilised from stores to increase the blood glucose.

[davetapson]

You wont get spikes because insulin is not dumped into your blood stream in response to high blood sugar.

 

I thought this is what I said?

[Leon Besaans]

You're right to use Hammer Dale but the spikes are a myth

 

The Myth of the “Insulin or Sugar Crash” during exercise…

 

 

 

Prof Google can justify anything. That is reality. Also, everyone of us are different, and we will burn fat and/ or carbs differently.

 

When we used to cycle with Cytomax many years ago, OMG, it was so damn good and everyone used it, now the buzz is 32gi. Tim Noakes, Gary Taubes, Peter Attia has turned the world upside down with LCHF stories, but its not for everyone, its clear and they tell you so much.

 

Truth is, you need to find what works for you, and what drives me crazy is all this fancy marketing and hype about this or that product with the shiny label gonna make you see gold medals etc etc. Its just not true. Ultimately a well balanced diet and truthfull fitness levels will determine your outcome.

 

For what its worth, I use UCAN for marathon type rides and mostly nothing for anything less than 2hrs.

 

Good luck in your search.

 

Regards

[jcza]

Prof Google can justify anything. That is reality. Also, everyone of us are different, and we will burn fat and/ or carbs differently.

 

When we used to cycle with Cytomax many years ago, OMG, it was so damn good and everyone used it, now the buzz is 32gi. Tim Noakes, Gary Taubes, Peter Attia has turned the world upside down with LCHF stories, but its not for everyone, its clear and they tell you so much.

 

Truth is, you need to find what works for you, and what drives me crazy is all this fancy marketing and hype about this or that product with the shiny label gonna make you see gold medals etc etc. Its just not true. Ultimately a well balanced diet and truthfull fitness levels will determine your outcome.

 

For what its worth, I use UCAN for marathon type rides and mostly nothing for anything less than 2hrs.

 

Good luck in your search.

 

Regards

 

Got nothing to do with Prof Google (or Prof Noakes). The research from reputable medical insttutions is freely available.

[V12man]

Spikes a myth ?

As this article says it's not, there are many that will say it's fact.

 

 

Glucose level spikes UP during exercise ARE a myth for people with normal metabolism function. - so eating additional glucose during exercise does not result in increased blood glucose levels - that is a fact.

 

BUT

 

What you might be feeling/seeing are down "spikes" (to coin a phrase) when you are running LOW on carbohydrate (either intramuscular or blood glucose), and when you eat highly available carbs (like a gel) you QUICKLY feel improved performance of your improved carbohydrate levels.

 

The trick to avoiding this inverted spike is to eat enough carbohydrate more regularly - so assuming you are not carbo loaded (and in fact even if you are) you should be eating/consuming at least or above the rate you are expending them - in practical terms this equates to about 1 gel (depending on size (of you and the gel/carb drinks)) every 30 - 45 minutes - or possibly more at balls to the wall racing pace. And you must start using them/eating early enough - so within the first 20 min of a race. Also you should bear in mind that the absorption rates of carbohydrate are different depending on what specific carbohydrate it is, and there is clearly a maximum absorption rate (Bosch/Noakes et al) of both fluid and carbohydrate that exists, and it is pointless for intake to exceed this.

 

This is one of those situations where slightly more is better than too little in performance terms - given that high carb loads have a tendency to upset your stomach, so you do want to be close to the number, but not wildly over - and if you are well carbohydrate loaded, then you can reduce the rate of consumption, and trade off stored glycogen for lower intake of carbs.

 

At race pace you WILL run out of stored glycogen somewhere between 2 and 4 hours (hitting the wall) and you need to have pre-planned your carb intake such that this does not happen.

[Wyatt Earp]

Glucose level spikes UP during exercise ARE a myth for people with normal metabolism function. - so eating additional glucose during exercise does not result in increased blood glucose levels - that is a fact.

 

BUT

 

What you might be feeling/seeing are down "spikes" (to coin a phrase) when you are running LOW on carbohydrate (either intramuscular or blood glucose), and when you eat highly available carbs (like a gel) you QUICKLY feel improved performance of your improved carbohydrate levels.

 

The trick to avoiding this inverted spike is to eat enough carbohydrate more regularly - so assuming you are not carbo loaded (and in fact even if you are) you should be eating/consuming at least or above the rate you are expending them - in practical terms this equates to about 1 gel (depending on size (of you and the gel/carb drinks)) every 30 - 45 minutes - or possibly more at balls to the wall racing pace. And you must start using them/eating early enough - so within the first 20 min of a race. Also you should bear in mind that the absorption rates of carbohydrate are different depending on what specific carbohydrate it is, and there is clearly a maximum absorption rate (Bosch/Noakes et al) of both fluid and carbohydrate that exists, and it is pointless for intake to exceed this.

 

This is one of those situations where slightly more is better than too little in performance terms - given that high carb loads have a tendency to upset your stomach, so you do want to be close to the number, but not wildly over - and if you are well carbohydrate loaded, then you can reduce the rate of consumption, and trade off stored glycogen for lower intake of carbs.

 

At race pace you WILL run out of stored glycogen somewhere between 2 and 4 hours (hitting the wall) and you need to have pre-planned your carb intake such that this does not happen.

 

Thank you sir.

So it still a spike and a GU every hour is asking for trouble.

[Leon Besaans]

Thank you sir.

So it still a spike and a GU every hour is asking for trouble.

 

Amen brother amen.

[V12man]

Thank you sir.

So it still a spike and a GU every hour is asking for trouble.

 

More like a low....

 

I personally struggle to eat GU - and the sachet is big, so I never recommend using the whole one at a time - but if you try half a GU every 30 minutes you should have no trouble if you are working hard enough. Each supplier has different sizes, so you have to sit with a calculator a bit to figure out at what rate to eat the stuff.

 

Eating real food does protect the GI a bit - but it is not necessarily as readily available, or as easy to swallow when you are working hard - and yes - I have breathed a bite of banana in before by mistake.... NOT fun... except for my race partner who laughed at the coughing fit... and promptly nearly fell off right in front of me... which did not help me either, because laughing and choking at the same time is something of a Darwinian experience..

 

 

 

Empty packets go back in the pocket...