Yesterday I went on my longest trek yet. 130km comprising of 120km of fast road riding and 10km (took 2 hours for this alone) of really steep single track mtb trail. I rode out, hit the track, had lunch, and then rode back. Left home about 5am, got back around lunch time. Plenty of stops along the way to refill my water bottle etc. I rode 30-35km/h on the road and never let me speed drop below 30 unless a hill proved to be too difficult. Even then I never let it drop under 20km/h.

What surprised me was the sheer amount of food and water I went through. I had 4 liters weak Pokari sweat (Japanese electrolite replacement not much energy in it), some fruit, some sandwitches, and some rice crackers. Went through all of that and was still hungry most of the day after that. Is it normal to require so much energy?

For me, a 143 lb masters road racer, typical average power for a long ride is about 550 cal/hr. I can eat about 200-250 cal/hr. At 200 cal/hr a 6 hour ride means a deficit of 1500 calories. Then there's the regular meals I'm missing. I eat breakfast before the start but I'll still miss the mid-morning snack and lunch. That's more calories that need to be made up.

Why would you be surprised? I'd burn between 3500 and 4000 calories on such a ride. That's quite a few sandwiches.

I'm more like 180 pounds with a 30 pound mtb/hybrid. I'll be 39 this year. The fact that I can do it and have energy left for the rest of the day is amazing given that at 230 pounds 5 months ago a miserable 10 mile ride almost killed me. I suspect that being heavier and riding a heavier bike more energy is going to be required to keep it rolling at speed. But, I can't ride a road bike on a mtb trail so its the steed of choice.

That does make sense. If you factor in 2000-3000 calories normal maintance requirementss, then 3000 calories or so for the ride itself that is a lot of food. Still I feel guilty eating so much after working so hard to get rid of the weight in the first place. I quickly found that if I don't eat a small amount every 20 minutes or so then my legs stop working. There is a limit to how much fuel the body can carry at any one time. Iggnore the messages and bad things happen.

Assume burning approx. 500-600 calories per hour ... so on a 6-7 hour ride that would be 3000-4200 calories.

Consume 200-300 calories per hour ... approx half what you burn. If you have been eating normally in the days before the ride, you should have approx. 2000 calories in storage to use. Between a good 500-600 calorie breakfast, your 200-300 calories per hour, and your 2000 calories in storage, you should be able to last 6-7 hours just fine.

When rides start taking longer than that, you may need to stop for larger meals to catch up on your calorie needs a bit. After the first 6-7 hours, I find I need to stop every 5 hours or so to eat a meal.

I weigh 165lbs and on a long ride typically burn around 700 Cals/hr. You should be able to get around 300 Cals/hr from internal fat stores, the rest needs to come from stored glycogen and carbs you consume on the ride. On a long ride you should eat as much as you can handle. Normally 250 Cals/hr is a good guideline but it's possible to process up to 400+ Cals/hr if you use the right ratio of glucose and fructose.

And there I was wondering why my body was demanding so much food. I think that day I probably ended up with a slight deficit despite eating small amounts all day. This week I'll have to increase the amount of food I take with me a little. Time permitting I want it to be a 160km. If I can do 130 including single track in that time then 160km on the road in the same period should be no problem. Finding a nice interesting course to ride with no repeats, that may be more of a challenge.