Hi fellow Pavletes,
during my last long ride (well, 5hrs, long for me) I stepped into what I call the “type 2A trap”. What I mean by that is going too hard in the early part when the legs are still good and using the type 2 muscle fibers too much. Doing so, you use way too much carbs, but still feel great. If your type 2A fibers are reasonably tranined, you can do that for some time and you don’t notice that you are using more carbs than you can take in. This inevtiable leads towards thew dreaded bonk.
Now my question is: Does anybody look at the “used kJ” data field on bike computer, use a fuelling app or even a glucose sensor. I would love to hear your experience.
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Tagging in @Kicikacsa to this as I am sure he was using “used Kj” for a bit 
Looking forward to following this thread!
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Yes i had the Supersapiens GCM for a while, but its so expensive.
Its definitely definitely helped to refine what im getting in my body during rides as you can see the effects - either bonking or spiking. Essentially i used to to make sure i was intaking liquid fuel every 10mins to have a more stable glucose line, avoiding big peaks or drops. Im using Hammer Perpetuem as a liquid fuel now, as it avoids any GI issues with my IBS…again bloody expensive…
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Hi Chris, as Pav notes, I have looked at the energy balance during long rides. Starting with where I am now. I have a fuelling strategy that aims to keep my defecit to less than 300kcal/hour. The longer the ride, the smaller I try to make the defecit. I do not ride against a kj output on my head unit.
The maths says that @200W average I would need to consume 720kcal/hour to be energy neutral. So as a minimum my plan is to consume 420kcal. I know what that translates to in terms of bottles / gels / bars etc. so I eat to a plan.
I developed this strategy whilst building up to my vEverest. Working with the energy drink formula that I posted and the advice of the guy I gave it to, I was able to consume 120g of carbs per hour. From memory this equates to 600kcal. At this level, I was able to ride >6 hours and ultimately 13 hours with a defecit of around 300kcal/hour.
One key thing that I learned along the way is that I don’t have to consume that much, but the smaller than energy defecit, the better I felt after rides and ultimately the more training volume I could accomodate. Basically anything over an hour or anything high intensity I fuel during the ride because it aids my recovery.
The maths for riding at 100w:
100w = 100 joules / second.
3600s / hour
100 x 3600 = 360,000 joules / hour or 360kj
the body is approximately 25% thermally efficient and 1kj is about 25% of 1kcal.
so 360kj of measured output ~ 360kcal of food intake
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So, you just keep it as constant as possible so that the equation works like that.
My random 500W exploits in the last session would most likely upset the balance and I would have to calculate how much off “barely touching the pedals” I would need to compensate. (ignoring additional effects like fat oxidation and non-linear effects like the energy systems of the body switching back and forth with a delay)
I’m still curious and will test one of these apps.
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I am very interested in trying supersapiens. Can never have enough data.
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From my perspective I see two elements here.
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Is how to counter/control and moderate the effort/energy expenditure early on in a ride/run.
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How to properly understand and apply on bike nutrition.
The first is something I have often seen newer riders falling foul. Pushing too big a gear at the start at a power or HR that just isn’t sustainable for the length of ride been embarked on. Pushing hard/racing up a climb to beat your mates you will start eating into your carb stores which is fine as long as you understand this and are refuelling properly on the bike.
So refuelling on the bike. Start straight away it is very hard to stay on top of your energy usage if you let it drop by not eating straight away. If you muscles can store enough glycogen for one hours effort and your doing a 5hr + ride you can’t in my eyes just wait for that cafe stop at 2 hrs before eating anything. You’re now in a negative/a hole and you won’t be able to take on and actually absorb enough to replenish what you’ve used. Equally you also then see the post cafe glucose high. Where a rider is feeling high after getting a hit of quick burn sugar and starts putting in a hard effort from the cafe only to die 30-60mins later.
You will often these days read about needing to train the gut and the 60g of carbs per hour or more. So you need to start eating straight away on a long ride but you don’t want to over fuel depending on your energy output. My thoughts are if you can consume and then burn what your putting in the tank rather than dipping into what is stored in the muscles, then that is the target and I see this is where I see continuous glucose monitors coming into play.
In my testing I know I can ride at a certain pace fasted from dinner the night before and do a 50-60 mile ride 3-4hr ish and only have a black coffee (no sugar) at the cafe stop. However I am ensuring I’m staying well hydrated and replenishing electrolytes. ALSO this is ONLY in testing and not something I would generally do and I might well be more fat adapted than many given I am a regular faster. Likewise I can fast from dinner the night before work all day, get in and go straight out for a 2hr base run before then having dinner. However I also know if I run a little too hard I can be flagging on the last 20-30mins which is usually from ergo/typeA personality kicking in and holding to the higher pace of others in the group rather than following my target pace.
So I tend to eat real food and not too many gels. I am feeling from 30-45mins into the start of my ride and use the little and often approach. I ensure I am carrying roughly what I have estimated from past ride data I need to consume plus some more. I find having a top bar bag is great to have as a snack jar. I have a plastic bag in there with bite sized pieces along with often salted cashews as I find this helps with the flavour fatigue. Then in my pockets I will have more plastic bags to switch out when I finish the one in my bar bar. I will only have one bottle with a carb mix in ( to help on sections where it might be harder to eat food) and the other been electrolyte mix.
I also work to another rule “DON’T DIET ON THE BIKE” “FUEL YOUR RIDES AND TRAINING”
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Some great information here everyone. Please keep us informed of your journey.
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@kevstorr that is far more eloquently said than I managed. I essentially agree with everything you have written.
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Thanks for the share on this. Really valuable info.
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The short spikes etc. should not make much difference as long as you don’t start them in a depleted state. That is why I start topping up from the start of the ride. Even if it is a longer effort at higher power after a long time in the saddle, as long as you are keeping up with your fuel intake you should be ok.
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To be clear, I did not ride without eating. I had 2 950ml bottles with 120g carbs each and drank at least 500ml per and in addition took one bar or gel on top of that per hour (more like per 50min).
My problem is the non-linear nature of carb use once the inefficient Type 2 fibers are recruited and the drop of fat usage once you get above FATmax. If I go at 300W instead of 200W, the carb usage is most likely not 50% more but way above that. I still haven’t found out how to feel when it gets “expensive”.
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I understand what you are looking for Chris. Supersapiens appears to be the answer. Everything else is guesswork. In the absence of that isn’t the answer just consume the maximum calories that your body can consume?
The other assumption you are making is that the issue is a fuelling one. What % of ftp is 300W?
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