I do fuel, as I said, just not to the same degree I do when I’m racing. I do pretty much what you say, a bottle mix and snack bars, cappucino and something else sweet. As opposed to when I’m racing of up early enough for a bowl of porridge, a bottle an hour, gels at certain points, etc.
HOW VERY DARE YOU!?!?! 
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Good summary. I think the recovery, hunger aspect, brain fog, are just as important for us who have to work too 
but since I have fuelled moderately for these, I am holding just shy of 4W/kg for this range and doing over 20 hours a week. Seems to help me at least. Definitely has taken a long time though of consistent work!
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4wkg at z2?
Who are you, cancellara on epo?
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with a motor too yes plus a toe from WVA
No I am not pushing low Z2 at that - just meant endurance broadly but the upper end. I just noticed that since training harder and fuelling more, workouts are just more effective.
Saying that, in the spirit of this thread: I do not pummel carbs for any endurance work - tbh it just feels to me at least it is not used and sits on my stomach. When I work hard, it evaporates it feels like.
Edit: pummel in my eyes means like 120 or something. I realise I am being SUPER scientific today!
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My upper z2 is ~3.7w/kg (female if relevant), so i wouldn’t think it’s terribly uncommon.
Also FWIW I think there’s a lot of room to move between ‘100g/hr for a 2 hour endurance ride’ and ‘1500 calorie evening meal.’ Might not make for as interesting an argument, but I suspect the majority of people will probably take a more moderate approach to both. I’m certainly not here to crap on what works for people, but I’m not sure if either of those two examples are the most useful/relevant starting points for recommendations or general advice.
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Yeah, as I reiterated above.
All of the things I wrote above can apply to “long Z2 too”.
Note the word in bold.
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Again - even more impressive stuff than the last poster. Much respect. What’s the take on this in your UCI world tour team? How are you looking for the tdf femmes next year?
(ISM z2 of 3.7w would put you at at 5wkg (@75% of FTP), perhaps pushing 5.5-6wkg FTP if your z2 is more like 60-70%, so stronger than AVV).
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Sort of correct. The fuel utilization was quite different, people who ate less carbs burned more fats for the same relative energy expenditure, but none of it helped spare muscle glycogen, which was utilized at the same rate regardless of fueling strategy.
The real point of the episode was that the whole mitochondrial reticulum is the real source of endurance, and that the mechanisms driving muscular fuel choice are decoupled from the adaptive stressors that improve endurance performance. Which is why the conclusion of that episode was: have a snack and go ride your bike.
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Woah there, Nelly 
Wildly off topic here, but I’m just a kid with an ex-competitive sport background, a slight eating disorder, and none of the skills or short power numbers necessary to even consider racing at that level. W/kg is overrated from a performance standpoint, IMHO.
I believe this is the study if anyone wants to have a look. From the abstract:
- Additionally, CHO feeding does not alter subcellular IMTG (intramuscular triglycerides) utilisation, LD (lipid droplet) morphology or muscle glycogen utilisation in type I or IIa/II fibres.
If there is more glucose circulating in your blood than is needed to supply the atp demand from the intensity you are cycling at, will you use that excess preferentially over fat oxidation?
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Sorry if my meaning wasn’t clear in posting that, I was just trying to add the background to Kollie’s post above.
The study was used to show that it doesn’t really matter if you fuel with CHO or not-mitochondria biogenesis is what makes you a better endurance athlete.
I think you could interpret this to support your claim that you don’t need to fuel workouts and it helps with weight loss. Or you could interpret it like I do, that there aren’t any drawbacks to consuming CHO during Z2 rides (and in my case reduces RPE helps make it easier to get all the calories I need for the day).
I think the main takeaway from the paper and the Empirical Cycling Podcast is that carbohydrate consumption doesn’t limit or suppress fat oxidation at those intensity levels.
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The idea posted above that carbs while riding wouldn’t allow you to use your fats for fuel, already sounded very Gary Taubes to me.
I can also imagine things just work differently for a sedentary type II diabetic or for a fit cyclist burning 700+ kCal per hour for multiple hours.
I didn’t get that out of the paper, and here’s what Kollie said above:
And Kollie’s main point of the episode:
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My limited understanding is that it’s very duration dependent. Short rides (at any intensity) will use more CHO than longer rides. As the duration increases, fat becomes a more preferred fuel source (regardless of available CHO?)
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Every single one of these studies contained only male participants, except the first, which had a 12:3 male:female ratio in 55 participants, meaning they had about 4 females in the cohort.
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I just listened to the latest Empirical Cycling Watts doc, too! It was a super deep dive. My main takeaway was that training matters more than energy pathways for performance. Would it matter for weight loss? Maybe - I didn’t get a strong read one way or the other.
So, for your friend, experiment with both extremes. Don’t eat for the first half of a 2-3 hour z2 ride and only eat low carb foods for the rest of the ride one Saturday, then try to overshoot recommended carb targets during a 2-3 hour z2 ride the following Saturday (or any day that has another substantial workout the next day).
For each ride - What felt better? What worked better for your health, training and your life off the bike?
What did your food choices look like after the ride? Were you able to sit down to a healthy normal sized meal after, or were you ravenous and ate more than you would, or more junk than you would normally?
How was your mood after the ride? Were you in a great mood or a sour one? Did you have good times with your loved ones at home or did you snap at them?
How was your energy both during and after the ride? Were you able to jump in to your other tasks for the day, or did you need a long nap and some couch time?
How did your workout feel the following day?
I know the answers to all of those questions for me (everything is a complete disaster with no carbs, lol). But I do believe that someone can have the opposite experience.
My opinion is that amount of knowledge about “substrate utilization”, krebs cycle, pyruvate, mitochondria, etc., or studies done on some demographic of people that you may or may not be a part of, is going to be prescriptive in any one individual case.
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I’m eating about 600-700g of carbs per day, off the bike. Thats roughly about 6g per kg (at 92kg). I can routinely, week after week, ride 8-12 hours with little (40g/hour) or no fueling on all the 2-3 hour workouts on my calendar. HOWEVER I’m timing my carb intake before and after. If I get busy at work and lunch/workout timing gets thrown off, I’ll eat carbs on the bike for those 2-3 hour endurance/HIIT workouts. If not feeling great I will push carbs to 60g/hour on those 2-3 hour rides. I eat to practice eating, because I appear to perform better on 5-12 hour rides when I do 60g liquid carbs plus eating another 30-40g every hour or two.
Yesterday I ate something like 750g of carbs, didn’t fuel the afternoon 2.5 easy endurance ride (because I forgot food), and felt fine last night and this morning. Joked about it in this thread, but it was true I slammed a lot (120-150g?) of carbs 90 minutes before riding, and another 80g immediately after getting off the bike.
It is really interesting to read how horrible some people feel during and after workouts, if they don’t eat carbs during the workout.
That is really rare for me, and the last time it happened was 9 months ago and here are my workout notes: “Woke and felt drained. Maybe part memorial services yesterday (she was only 2 years older than me), and perhaps allergies because my nose has been running like a faucet on rides. Started out and felt better, up until about 2 hour mark. Started the 2nd tempo interval and my legs felt like jello. Fought to salvage that 2nd interval but it is UGLY. Limped home and legs started coming back around the 4 hour mark. Ate a good breakfast and had eaten 120g carbs at the 2 hour mark when the shit hit the fan. Drank 5 bottles of water. It was 60 degrees and not warm.”
In my experience, off-the-bike stress can be a bigger factor than carbs.
Thats why I say “experiment!” and figure out what works for you. Don’t forget to consider outside stress, its a killer in more ways than one.
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