Carbs for zone 1

Is there a sense for how approximately many carbs per hour to ingest in 3-4 hr mid zone 1 rides?

Is the variation of the Fatmax so big that one can’t come up with a general range?

Hello @micomico

Hope you are doing well.

Here is some data from some of the athletes have tested.

Carbs in Grams/Hour at FatMax

From Inscyd Testing

From Aerotune Testing


Thanks, Steve, exactly what I needed to see what the typical ranges are.

@micomico they can vary more than this just so you know but this is a start.

Presumably your absolute power at LT1 will have a big affect on the amounts of carbs used.

It depends what you are after? If you want tp increase your fat combustion then eat low to no carbs heading into the ride as well as for the duration. 3-4 is a long time on the bike. I have athletes spend the first 60-120M without eating, then start eating carbs. Sciene is leaning towards 60-90g and even 100+g/hr so if you are training the gut, I would lean towards 60-90, if you are not close to that now,then start at 40-60g. Per @steveneal some of his test data is within the ranges I mention for fatmax. In the end, it depends what you are after or trying to accomplish. Hope this sheds some more light for you…

Thank you, it does. I remember feeling weaker after 2 hours of high zone 1 endurance riding with no food/carbs, so have been eating since. Steve Neal gave me some good info about that, suggesting up to 90g/hr.

Should I assume, on long endurance rides, that taking in the carbs burned at my FaxMax zone per my INSCYD test each hour is a good guideline, assuming I stay at the zone?

@micomico be careful of too much reading…

If you are riding in Zone 1/2 (depending on your model) around fatmax, and rides are under 90m and honestly in that zone, you can likely just drink water (or water and bcaa)

If the rides are 90m or longer you should take carbs in during the ride.

I don’t have any experience based on @Fpike so can’t comment on NOT eating for the first 90-120m. If the riders I work with are riding longer than 90m, I always suggest starting nutrition from the beginning of the ride.

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Something I need to address as well. I recently had a vasovagal attack that may have been due to dehydration as my blood plasma levels were low, I ended up on an ECG, constant blood pressure monitoring and a drip in A&E for 4 hours.

I have never drunk or eaten on the bike unless a really long mtb ride (think 40-50 miles and 7000-8000 ft climbing). So I guess I am pretty much fat-adapted as much of my riding is below VT1. So my training for this winter is not just the cycling, but to drink 1-1.5 litres during every 1-2hr ride as I am a heavy sweater, and now I need to think about fuelling for longer rides. Int will be interesting to see any positive effects on fatigue, with during and after a ride

@steveneal, agreed on the carbs at 90+M and nothing at 60M or under. I probably was not clear in that if you can idenify true fatmax via testing like INSCYD, then you can train at fat max and raise it like you would FTP, thus I use the first parts of longer rides to do this and force the body to use fat as fuel, then start eating for use of carbs. So i guess it all depends on what you are after truely train fatmax or train the gut or just be sure you are fueled for your ride.

Always appreciate your excellent commentary!!

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Yes I agree on the raise fatmax like FTP (although I don’t agree in FTP as it is screwed up emoji face here)

I was just try to say that I have no experience in limiting carbs early in a ride myself.

However, I would say that looking at not using carbs or starting a ride fasted does not always lead to a person burning, using, utilizing more fat…this I have seen on my metabolic cart.

I also know @micomico pretty well and sometimes training in this zone 1/2 range for certain people at certain times will NOT lead to overall fitness gains. I have seen this in many athletes trying to follow a zone 2/fatmax protocol, or polarization training plan. If there fat max is 100 watts, and they use this alone to ride their endurance with a 250-300 watt maximal aerobic power, they will train too easy during endurance and NOT improve.

On a bit of a rant here, but many cyclists who are trying to improve try to follow an idea that doesn’t make sense for them at that time.

It does matter what you are after. I just find that most recreational athletes trying to improve are focusing on the wrong thing when they begin, which holds them back from improving.