Hondo Gravel

How long can you ride without calorie intake? Only drinking water.

CliffordK

Hard to say. Flat, hilly or steep?

I can probably hit about 50 miles or so without eating anything. Maybe further, but I like to force myself to stop and eat a few calories every 50 miles or so.

Hit 150 to 200 miles or so, and I'm eating everything in sight.

I have noticed that on the more challenging hilly courses, stopping and eating something can truly give one a boost of energy to continue to hit the hills.

gregf83 

100k on the weekend after breakfast. Have gone 160k in the past just to see if I could.

Machka 

Theoretically ... it depends what you've eaten before the ride, but let's say that a person who has been eating normally (not in deficit) had about 2000 calories in storage in liver and muscles, and let's say that the person ate 500 calories before setting off on the ride.

Theoretically, that person should be able to ride about 5 hours.

But reality is sometimes different from theory.

DrIsotope

How far I can go without eating and how far I should go without eating are two very different numbers. It varies widely from day to day. For a typical 30 miler in moderate temperatures, I might not even drink. I've eaten nothing on decently paced 70-80 mile rides. But if I leave the house intending to get to the century mark, I'm generally eating at fixed intervals because I know I'm going to run out of reserves.

canklecat

Differs for most of us, depending on our fitness level, health factors (diabetes, for example), etc. There are fewer differences for elite level athletes, but that ain't most of us.

As I've become fitter and lost a bit of weight, from 175 lbs in 2015 when I resumed cycling to 160 now, I've been able to go longer without eating. I don't often stop at fast food joints for lunch on rides shorter than a metric or full century. I carry a couple of energy bars.

Problem with energy bars can be the ingredients, for some folks. I'm lactose intolerant (except for yogurt, oddly enough). And legume based protein makes me gassy. So I have to avoid certain energy and protein bars during a ride, or I'll be turbo charged and a smog hazard to any cyclist unfortunate enough to be in my wake.

If I eat too much on a long ride I slog home feeling burpy. Did that on my last century. Stopped at the 70 mile mark to join some friends for dinner at a German restaurant. Ate way too much heavy food and three delicious German beers. Then I was a foam machine for the last 30 miles home.

So now on rides up to 40-50 miles I just carry a tube of glucose tabs, the kind sold in pharmacies for diabetics. I've had occasional problems with hypoglycemia since childhood so I know the drill and symptoms. But if I eat properly the night before and about an hour before a ride, I'm good. My usual pre-ride meal, day or night, is a bowl of oatmeal with yogurt and a banana. That's good for a few hours.

Candy would probably do as well. Chocolate is nature's finest energy bar and health food. That's my story and I'm sticking to it. But chocolate makes a huge mess so I quit carrying it on rides. Glucose tabs in those plastic tubes are neat, clean and fit in a jersey pocket or saddlebag.

Saturday I rode a hard 40 miles with hill repeats into the wind and hard sprints with the 15 mph tailwind. It was mostly a conditioning ride, not casual cruising. I felt a bit bonkish after 30 miles so I chewed a couple of glucose tabs. That was good enough to get home. Then I was ravenous and ate everything in the house. Good way to get rid of those leftovers.

Water is critical too, especially for folks prone to blood sugar imbalances, thyroid conditions (which I also have) and anything that can disturb our normal temperature regulation including some prescription meds. Ditto, electrolytes for me, although some folks don't need it.

hubcyclist

I've gone 3.5 hrs (65miles) in recent months without actively eating during a ride. I routinely ride indoors up to 2hrs and never eat and many times I workout with just having had my morning latte (or 2 or 3 lol). Just as an example of workouts I've done recently, Saturday I did 2hrs with 4x20min intervals near FTP and yesterday was 2hrs with 3x30mins at 85% of FTP, each about 1500 calories worth of work. I haven't done a lot over threshold in a while so if I can't speak to how that affects me.

Altimis

Used to ride 3 hours straight without food and water (Yeah, no water!)

Its night time so its chill and silent so I decided . . . . (that's why I can manage to ride without water, its chill out there)

Just some crazy ride, not recommend, obviously nuts.

How I feel? last couple miles I felt a little drag, bit extra craving for sugar (or salt? I am not sure) but nothing special.

Of course, I eat like crazy after that lol (actually I just want to reward myself after crazy ride).

What I eat before ride? just black coffee, wait a bit and then I go.

Seattle Forrest

Rule of thumb is if I'm planning 3 hours or less, I don't need food. Can push that to about 5 hours, but prefer not to.

Peanut M&Ms work really well on the bike, and on skis too.

Drew Eckhardt 

At least 4-5 hours, although on 5 hour rides I like to eat an energy bar after 4 hours because I'm getting hungry and beyond five hours eat a Clif bar every 20-25 miles because back-of-the-envelope calculations suggest running out of glycogen is likely and I don't feel like dealing with that far from home. Around 100-140 miles I'm getting tired of sweet energy bars and want a little real food for variety - a chicken drumstick, sushi roll, 1/4 pound of Chinese food; but not much because two drum sticks gave me a bellyache for hours.

Drew Eckhardt 

It's more complicated than that.

You can't even move muscle glycogen between different fibers in the same muscle.

Conversely, a lot of your energy comes from body fat. As ride duration increases thus decreasing the maximum sustainable pace to your aerobic threshold, your energy substrate utilization shifts to fat. On 5 hour rides you can be at 60-80% fat.

IronM

Personally, when properly fueled beforehand, about 2 hrs of hard riding before starting to feel hungry. I can go longer, but performance begins to drop after that. Even on a 2 hrs ride, I usually carry one bottle of drink mix (Infinit Go Far). I see no advantage in draining the tank to zero.

Hondo Gravel

Wow I didn’t expect the times to be that long. 2 hrs or less I won’t eat but more than 2 hours I will have a cliff bar or some crackers at the 90 minute mark. When I rode Katy Trail last summer I would have some energy drink or food every hour since I was basically touring having an adventure. I didn’t want to get tired, my longest day on the Katy was 96 miles with regular refuels every hour.

CliffordK

The Katy always had somewhat more rolling resistance than bare pavement. 20%?

Anyway, that has to be factored in too.

caloso

I’ve dome 2 hours fasted from the night before.

Machka 

The general recommendation is something like ...

Under 2 hours -- no food needed, but you might want to bring a granola bar just in case.

2-4 hours -- aim for about 100 cal/hour, but it is good to have a little bit extra on board.

4+ hours -- aim for about 200 cal/hour. And if the ride goes over about 8 hours, you might want to have something that resembles a meal somewhere in the middle.

This is not set in stone, of course, and will depend on a number of factors including weather, fitness level, etc. But if you're unsure, this should get you through a long ride.

work4bike

I hiked the Appalachian Trail (AT) in 2006 and my biggest lesson on that hike is that I learned just how efficient the body is, or can be...

On a hike you must ration your food, simply because you can only carry so much and there's not a store at every corner, unlike a bike tour. In the beginning I do remember being grouchy and experiencing times where I felt very weak and light headed, but over time my body changed in incredible ways, it became extremely efficient at burning fat as fuel.

Long story short, I now keep my body as a fat-burning machine, by not eating in the morning and going on a long, hard ride and doing some stuff at the gym.


And then I saw this article and was surprised that it's basically how I train; however, the article probably wouldn't have caught my attention without the experienced I gained on my AT hike, because knowing and experiencing are two very different things.

It's tough in the beginning, you will feel weak, foggy-headed, and grouchy, but once you cross over to the other side it's an incredible feeling.

Excellent article!!

How To Tap Into Fat For Fuel | Triathlete.com

TimothyH

^^ congratulations on the AT hike and thanks for that article. It is very interesting.



-Tim-