So about 370 for the oats, 100 for the banana, and the rest is more or less fats. Fats slow down digestion significantly, thats well known, so you may not be getting the benefit of the carbs till way later. Apparently fats them selves can take up to 40 hours to digest (heathline) . but it depends how long the fat chains are and therefore varies.
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Yeah now that you mention it I did get on my bike rather quickly after eating breakfast (maybe 30 min after finishing my bowl). I do long distance triathlons and ride 120-150 K every weekend. So the distance isnât anything my body shouldnât be able to handle. However as I mention above I usually would also have extra carbs in form of malto in my water bottle and havenât had any problems in the past. Maybe I was always in the brink of underfueling without noticing and now that I did take these extra carbs with me I actually felt the symptoms??
In any case I will definitely pack as much as I can carry next weekend and eat breakfast earlier.
As I am informed after about 2 hours of moderat exercise your body starts to utilize fats for fuel as well. Thatâs why I make sure to get in some fats as well. I didnât know digestion takes that longâŚ.on any regular weekday I eat that same breakfast around 7 am and when itâs time to get lunch at work at 11:50 am I am already starving again. So I felt like my body is done digesting the fats from my breakfast rather quickly.
Maybe thatâs more to do with gastric emptying than absorption. Assuming theyâre different processes.
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At 160w and 64kg I think 60g of malto per hour should be enough. I find the easiest thing to do is make one super concentrated (750ml) bottle with most of the fuel I need for the ride. So for 4 hours approximately 200g of malto and one scoop (~25g) of my favourite sport mix for flavour. Then I add salt (depending on weather) and some caffeine as well. It is best to prep this in advance and mix with hot water to get it to mix well enough. Leave it in the fridge overnight and your good to go.
You can dan plan and drink every 20-30 minutes such an amount that it your bottle is empty with maybe 10 minutes left. That is like 80-100ml every 20-30minutes.
Then I have a separate bottle with plain water that I refill if needed, usually easy enough to get water. And maybe have a bar or two to get in some solids (though I prefer to go without or with gels) and for emergencies.
That should get you through 4 hours without carrying lots of food or stopping for cafe breaks. I donât usually like stopping, but if you like that, then adjust accordingly.
Donât fuel with fats before or during a ride. As mentioned here already they just sit in your stomach and cause GI problems, same goes for high-fibre foods or proteins. If you want to limit carbs, you can limit after the recovery period after a ride.
If you want more tips on optimizing your on the bike fueling, the following threads helped me a lot:
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Thank you!!
I heard someone mentioning the same strategy like you did. But how do you make sure that you donât produce a very hypertonic mixture in your gut? Having all of the malto in one bottle is a very very hypertonic drinkâŚ.
It is important to also regularly drink from the other bottle with plain water. That should make the situation in your gut better. Either way youâre going to need fuel. Eating a carrot cake during a stop isnât going to be good for the osmality either.
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So it is more of a âlisten to your body and try how much additional water and solid food you need/can takeâ kind of approach, right ?
It takes some training and experience to figure out what works for you. I never had any problems with this approach.
It gets more complicated if you increase the power though. At 200w youâre going to 90g/hour and that means that besides glucose (malto) you also need to include fructose in your fueling strategy. That is where most issues with GI discomfort start.
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I am still working through all the science, but one thing is clear to me is that these rules are very generalized and numbers like these not tuned to the individual can lead to over eating or possibly under fueling but less likely.
The first thing is moving from fat to sugar as an energy source is not a light switch. one does not switch off as the other switches on! they are not exclusive. The two work in parallel and both vary with exercise intensity levels.
I know base on several years of powermeter data, that my burn is around 6 calories per min , rising to 8 or 10 if i am in âthe alpsâ But add that information to my calorie consumption and it is still a 60% fat burn over the course of a century ride. I will eat tacticaly and pop a gel 5 min before a particularly nasty climb, if i feel the need
At least for me, which is why i say it needs tuning to the individual, that has been my experience. I am not saying the numbers are wrong on average, but asking are they right for you ?
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Obviously they are based on generalized numbers. No one rides around with oxygen mask during their regular rides. In fact most (me included) never have done so anyway to determine their fat versus carbs oxidation ratios. It is also dependent on your efficiency which is dependent on your total training volume I guess.
I do find your 60% fat burn very optimistic though. I believe that 50% over longer endurance rides is more realistic, however I donât have any sources at hand right now.
At 200W thatâs approximately 750cal/hour or 375cal from carbs or 93g of carbs. However, indeed, these are guesstimates.
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If you say ~ 375kcal/h from carbs, where do the other 400 come from ? Is it stored fat or fat from fuel during/ before the ride ?
To be honest, that doesnât really matter either way. No need to ingest fat during rides for fueling. Plenty of fat available to burn, even at low body fat %.
Iâm no expert, but I believe fat metabolism can take a significant amount of time, so consuming fats during exercise in order to fuel that specific ride is not recommended, by the time the fats are available for energy you are probably already done.
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@Derailleur You are right, it does vary depending on terrain, and therefore intensity and yes I had a quick look and PBP which is 1200km and about 10,000m climbing most around 6-8 % grade was around 50%.
Long distance are my game , so i watch this stuff like a hawk
EDIT
I just looked at yesterdayâs training run, 206km on mostly fat. 4220 power meter calories burned , for 500 breakfast and 1300 on route. so that was about 58% body fat. Allowing a 5% error on the powermeter woul give us 55%
J
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Hi @jlnzhrl, another thought, maybe off-topic, but parallel in the quest for enjoying longer rides, is how consistently were you riding in endurance zone on this ride? Would you be willing to share a screenshot of the power profile? Are you consistently 60-70%, or are you averaging 65% but spending chunks of time over threshold (like on climbs) & then freewheeling a lot which then brings the average back down? Itâs amazing how taxing these flourishes become. Too many punches above threshold will eventually knock you out. Theyâll dramatically increase your carbohydrate reliance. And was the ride solo or in a group? If riding solo you can govern your power output a bit, but if youâre chasing someoneâs back wheel youâll be at the mercy of the group. I find I get away with it up to about three hours but after that I start to fall apart because of muscular fatigue & probably fuelling too. On solo rides I aim to spend less than 1% at tempo & above. I have allowed groups to drop me when Iâm over budget.
Hereâs a group ride that wrecked me (to be fair it was after 2 hours of solo endurance with 9% at tempo & above, so really itâs 7h duration)
And hereâs a mostly-solo audax ride that was hard but didnât wreck me (apart from crashing 
)
How do you determine your oxidation rates?
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That math is very flawed: you have lots of glycogen stored in your muscles. Thus, you canât assume that the difference between total energy expenditure and the calorie-from-carb-intake comes from fat. If that were true, people who wanted to lose weight would just need to do long, un- or underfunded endurance rides.
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Also: what about energy from muscle degeneration due to underfueling (or even unfueled)?
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I always try and stay in my designated training zone for a given workout. Yes I did spend 10% in tempo zone but that wasnât a problem in the past during the exact same ride. I donât spend much time above upper zone 2 limit for longer than 30s at a time. Maybe during accelerating after a red light or a short hill I will go over my zone 2 ceiling but not for too long which is why my heart rate hardly exceeded zone 2.
As you can tell from my heart rate dropping at around 4h, thatâs when I gave up my power goal for that ride and still âbarelyâ made it home.
Here is the exact same ride on another day.
Not only did I spend more time above zone 2, I didnât feel totally exhausted afterwards. So I really think this is more of a fueling issue than it is a fatigue problem. But you are right, I could try and minimize the time in zone 3 but from my observation the 10% come from very short timespans accumulating over the +4h ride which I think is normal if you want to accelerate properly (not sprinting but also trying not to keep the cars behind you waiting).
Ps: I almost exclusively train solo for the same reasons you mentioned.
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Looks like ~24% Z3 and Z3+ based on power to me?
That is alot of Z6 and Z7 time wise for a Zone 2 ride IMO (I just checked a few of my 4.5 and 5 hours rides, less than 60 seconds Z5 and above, rolling hilly courses.)
HR zone wonât represent these efforts because of HR lag.
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