kuan

Most recommendations are between 30 and 60 grams of carbohydrate per hour. This doesn't really add up, say for a 6 hour ride that burns 5,000 calories. 720-1440 calories total? Is that the maximum one can replace on a ride this long?

My relevant stats:

52 years old.
3 hours or 40ish miles on just water and I'm done.

Question:

If I eat 600 calories that gives me another hour?

BloomBikeShop

Those are general recommendations based on what your body may be able to absorb within a given timeframe. You won't be able to replace every single calorie burnt during a ride like that (nor would it be practical). You also have to factor in pre- and post-ride meals, burning fat for fuel, etc.

On your long rides, start replenishing calories within the first hour, and see how you feel then (i.e. don't wait until almost three hours and only then begin consuming calories.) That's a good first step and the results can inform future decisions on in-ride fueling. It could give you another hour, maybe two more hours. It could also show you the limits of your muscular endurance. There's so much to learn!

Iride01 

Yep, as said, that is what the body might absorb or be able to handle during a ride. Also, too sweet a drink might give you an upset stomach and even though your muscles have the glycogen stores, you won't want to do anything but get off the bike and puke.

I might do one or two hour rides on just straight water. If I know I'm riding longer, then for certain I'll be drinking 100 to 180 calories of carbs per hour of ride from the start of that ride.

Oso Polar

Not necessary. May be. May be not. I've done centuries on just water and it was easy peasy (but not fast), so 3 hour limit may not be necessary only the nutrition issue. I can definitely ride for longer without any food - I don't recommend it though because if you'll try to go too far and too fast you may bonk or simply eat everything within your reach during next couple of days after the ride and gain a few pounds. Again, it depends. If you are accustomed to low carb food you'll fare much better with less food during the ride.

canklecat

Depends on overall fitness, effort/energy expenditure for a particular ride, whether the body is conditioned to burn fat if needed, heat adaptation in summer, maybe a few other factors.

Sunday I rode 51 miles in the afternoon with temperature in the 90s. I kept the effort to what Strava calls "moderate", mostly using heart rate as a guide. Strava claims I burned 4,117 calories, based on probably flawed data from my bike computer. Wahoo claimed 3,180. Dunno, I'm not really concerned about that since I'm not trying to lose weight.

A couple hours before the ride I had my usual morning energy/protein drink -- cold coffee with whey protein powder and whatever other supplements I feel like adding. Leftover Domino's bbq chicken chunks, a banana and Clif bar. Maybe 600 calories, tops.

During the ride I had one gel (100 calories) after the first hour or so, and one Clif bar (250 calories) the next hour or so break. A Monster cold coffee drink each time (220 calories x 2). Several homebrewed and store bought sports drinks, maybe 200 calories total between the lot. So, around 320 calories the first break, 470 calories the second break.

Definitely a calorie deficit, no matter whether Strava or Wahoo are accurate, even if they exaggerate quite a bit. But my main perceived problem was fluid intake. I thought 24 oz per hour would be enough but I should have been drinking closer to 32 oz per hour, maybe more. I didn't feel hungry with the intake I had, but did feel thirsty constantly and even stopping every 1.5 hours to refill at a convenience store I still found myself restricting water on my second bottle to avoid running out before my next pit stop. Rather than push my luck and risk heat exhaustion I eased way back on effort and finished my second bottle as I reached the planned rest breaks. I kept rest breaks to around 10 minutes or less.

Part of my problem Sunday was failing to stick with my plan of riding mostly Zone 2. On a few segments I felt pretty good and expended a lot of energy on 30-second sprints until my heart rate alarm sounded, then backed off. I really need to stop doing that. There's one steepish uphill segment where it's appropriate and sometimes necessary to sprint to merge smoothly with traffic. Otherwise I can afford to do a steady lower effort on most segments.

I'll probably try to eat a bit more next time and definitely drink more. Not sure whether I'll add a third bottle or plan convenience store stops more often.

(FWIW, I'm 62, 5'11", 150 lbs. Fairly healthy, definitely not the fastest old dude in my area, but in the upper third. Very middling on most segments, maybe upper third on some, all ages included.)

adamrice 

Yeah, with all of Canklecat's various provisos in mind, the rule of thumb is that we've got about 2.5 hours worth of readily accessible energy in our body, and after that, we have to rely 100% on burning fat, which is when we bonk. So it's not surprising that at 3 hours, you're done.

I've been pushing up the mileage on my Saturday rides lately (from 30-40 miles to 60-70) and have started using energy gel, although I'm still pretty sparing with it. (Aside: I found a recipe for homemade energy gel, and made a big batch. It's disgusting, but I hate to waste it. Which may explain why I'm sparing with it.) So far I haven't bonked, although that might just be me.

Iride01 

No.

You don't have to consume any Calories. Your body will be using what it had stored. This is a combination of fat and carbs stored in various ways. Fat tends to be used at a steady and slow rate during slow and fast riding. Carbohydrates are able to quickly be converted to energy and are used to a much greater extent when you are making a big fast effort.

However, if you want to be able to do sprints and hard fast climbs up hills to keep up with others, then you'll need to supplement your bodies reserves with carbs as they can be more quickly absorbed in the gut and replete your glycogen stores that fuel your muscles. If you ride hard constantly then it's estimated most only have enough glycogen stored to go two hours. So consuming carbs during the ride will help you maintain glycogen stores longer so you can do an extra sprint or climb before the finish line.

If your riding doesn't include times when you try to out do yourself or show up others, then any talk about using carbs might be moot. As long as you don't out pace your bodies ability to convert fats and other stores to muscle energy.

I've oversimplified some and many could probably nit-pick the simple way I generalized. So if you like to read, this website is very old and was even old when I found it 10 years ago. It gave me a pretty good understanding of things. Some might be a little dated, but it's basics still hold up well I believe. So read some about fats, carbs and proteins and very much read about physiology for nutrition and performance.

NEW CYCLING PERFORMANCE TIPS - Table of Contents

I haven't been to it much lately and it can be hard to navigate and some pages don't let you get back to square one. But there is a lot of info here to glean and the site was built by a doctor that also cycles and was looking to further his understanding of what he encountered while cycling.

He also wrote this book a long time ago and it is a good read. There are again some dated concepts, but it still holds up well.

Carbonfiberboy 

No. 600 calories will probably have you barfing in a ditch rather than riding that extra hour. It's actually a bit complicated. I've done a lot of experimenting on myself over the years. I suppose the first thing to know it that people are differently talented in the number of calories per hour they can move across the stomach and intestinal walls. It is said that RAAM (race across America) is not a bike race, it's an eating contest. It's also well-known that this. like any talent, is also trainable, but it takes a lot of time, riding and eating lots for months. Anyway . . .

Most people can move ~250 calories/hour across the stomach wall. I don't know why people say "stomach wall," leaving out the intestines, but it's a good way to think about it, because it's in the stomach that you'll notice problems. There's a thing called osmolality, which refers to the concentration of the stomach contents. If osmolality gets too high, stuff stops move across the stomach wall and you get "sloshy stomach" when the stomach simply stops functioning and eventually you bonk because you're not getting any nutrition. This is largely because blood flow to the midsection is sharply reduced when exercising, especially climbing. That's usually when I see people on long rides, standing beside the road wondering what happened to them.

That might be more than you want to know, but it's the reason for this: If you want to ride long, start eating small amounts every 15' from the start of the ride and continuing for the entire ride. Shoot for 250 calories/hour, almost all simple carbs. I've used this system on doubles before I found better stuff: Break a Clif Bar into quarters and put them in a jersey pocket. Open the package on a second Clff Bar. Eat 1/4 of the bar every 15'. When you're done, start the second bar. When you've finished those, get 2 more out of your saddle bag. When you can't eat another Clif Bar, stop at a mini-mart and eat something else, anything. By then, outmoded interests like taste and consistency won't matter. I know a rider who toured the California coast eating nothing but Hostess cupcakes because they never upset his stomach. A guy rode RAAM on mostly burritos and pop-tarts. I once ate a muffin, paper and all. Whatever.

The reason that the above works it that your body will fill in the rest of your energy requirements through fat burning. It'll also burn a little glycogen, but if you eat as above, not much. I did a 250 mile ride in 15 hours elapsed and didn't bonk, not even close.

There are a lot of products out there that'll work. My wife eats almost nothing except Ensure on long rides and she's not the only one. An elite of my acquaintance rode a 508 on 19 bottles of Ensure and anything else he could fit in his stomach. Hammer makes a variety of products for the long distance rider, but they're a bit costly if one does a lot of it. Worth a try though, just to see. Some people eat boiled potatoes, some sandwiches, some gels, some dates, any carb thing you can get down that doesn't come back up. That last is the important thing.

It's also important to drink plain water to dilute the food, limiting stomach osmolality. Not drinking enough when you're eating is another show-stopper. "They say" 6 oz./gel, something like that. Gels, especially Hammer Gel in their 6 oz. flasks is another common fuel. It's sometimes called "fueling" rather than eating because that's what you're doing.

kuan

So basically find something that doesn't bother you and eat a bit a time, I also find I can't drink commercially sweet drinks so it's water for me.

I also get that the more aerobic I am the more fat I burn so that saves some glycogen. Gotta get the fitness to a level where I enjoy my ride and also am able to get to place I want to go.

Drew Eckhardt 

You can only digest 60g of sucrose plus 30g of fructose an hour, noting even that's unnecessary with 2/3 to 3/4 of your energy coming from fat.

Also note that you're not going through 5000 calories in 6 hours if you can't average 20 MPH for five hours in flat terrain on a drop bar bike.

Less will probably work. You can figure it out empirically.

Iride01 

You say you can't drink sweet drinks. And that is a problem for me and others too. Don't rule out diluting them. Or trying various mixes. I used to use a 40/60 to 60/40 water and crangrape for my rides. Taste watered down till you get riding. Currently I'm using Hammer's Heed drink mix, and mixing 100 to 150 Calories per 24 oz bottle I take with me. My son thinks it taste too dry for him, but I like it. He likes his GU drink mix and also uses gels and straight water too.

Putting my carbs in my bottles means I don't have to remember when to eat something or carry it. I only miss eating something toward mile 50 or so of a long ride and a box of raisins satisfies that.

But regardless, you still don't have to eat or drink any food. Plain water is all you need to work at a slow pace. Your body has all it needs till you get down well below what your ideal BMI is. Plain water for many bottles in a short time brings up the question of electrolytes though and that's another sticky discussion.

In the end, do what works for you. I don't see where you have disclosed if you are even having an issue or concerns. So much of this discussion may be way off from where you might have wanted to go.

kuan

Haha true. In the beginning I was just wondering how I would ever get to those century rides but reading through the replies and thinking it through in my head it's a matter of going slower and managing my nutrition properly. Also picking up little bits of info here and there helps overall.

Seattle Forrest

For what it's worth, the last ride I did at that distance (51.25 miles) burned 1,686 calories for me. It was hilly, and I'm heavy. Not fat, but built like a football player. The way Strava works, it should at least do a better job than a heart rate monitor unless it's windy or you're drafting, I wonder what's up?

canklecat

Dunno, I don't worry too much about calories since I'm within a couple of pounds of my optimal weight. At 5'11" and 150 lbs, I could gain another 10 lbs and still be okay.

But folks who do rely on calorie estimations are rightfully frustrated. My XOSS G+ bike computer definitely exaggerates calorie burn, a common complaint among customers. App development has stalled due to the pandemic.

I usually back up my bike computer logs with my smartphone, via Wahoo Fitness or Strava, and those are usually more conservative. But I still doubt I actually burn 2,000 calories per typical 20-30 mile bike ride at zone 2 effort.

I think my estimates are skewed by erratic heart rates, a common issue with my auto immune disorder and meds. Some of my meds artificially increase my resting HR. And when I'm riding at a perceived zone 2 (not huffing and puffing for breath, no leg burn), my heart rate often escalates to zone 3-4. So if the app or computer uses HR for calorie and power estimates, it's gonna be way off.

Carbonfiberboy 

For calorie burn on my single bike, I look at kJ. For day-to-day, I look at the scale. Going back to the OP, calorie burn doesn't really matter for riding, only if one is trying to alter one's body weight. The only thing which matters is how much or how little of what one can tolerate on a particular ride, which is going to vary for everyone and every ride. So it's complicated and thus everyone has a different experience, theory, and practice. Just saying "it's complicated" of course isn't at all instructive. However there is this BF thread which revels in complexity, rolls in it, and from a certain perspective, is fun to read. Thus:
https://www.bikeforums.net/road-cycl...-what-eat.html

srode1

25 to 30% of the calories burned on a ride is a fairly standard rule of thumb. My stomach can tolerate (with training) 400 calories an hour but not sure how much of that is absorbed and the only time I would try that is on rides like 10 hours. For a 6 hour endurance ride I target 220 calories an hour. What you can absorb in different scenarios (effort, heat, water consumption rate) depends somewhat on the sugar combination you are taking in. You will know if you overdid it, your stomach starts to feel full and sloshing around.

ZHVelo

I recently bought energy powder (iso active), tastes quite nice and works really well, also contains some electrolytes. So on a long ride I would have two bottles of that and 1 bar for every hour I ride after the first. So that is 120 + 120 + 124 + 80 (I use two different bars, they are more like musli bars, not specific energy bars, those are just overpriced for nothing). So I have about 450 calories for a 3 hour ride.

That is more than enough, I could also easily do it with just 350. And depending how hard I go, I do burn 4-5 times that amount. I have done 2-2.5 hour rides without anything, and it works but towards the end my stomach gets angry.

richardwilson

It is essential to have highly nutritious food especially when you go cycling regularly.

jack pot 

anyone taking HUEL ... i've been on & OFF it some

gios

Cycling fits in with my diet. Have been low carb high fat more than a couple years now. Which has also led me to time-restricted eating (TRE) and intermittent fasting, as well as OMAD (one meal a day). Daily food log. No snacks. At least 7 hours of sleep - up to 9. No vegetable / seed oils. No sugar (as much as this is possible, as FDA food labeling allows zero to be shown if amounts equal < half a gram).

Time-restricted eating

The Fasting Cure Is No Fad 8-1-19