So I finally decided to get some advice on this. I've been told several times by different people that you really cannot absorb more than 150 cal. per hour when riding, and I've been following that logic without any issues on rides up to 3.5 hours. However, whenever I get into the 4 to 6 hour territory, where I try to consume around 600-800 cal. through gels and sports drink, at around 5 hours I tend to get a little loopy and finish pretty spent. The question is, should I take in more fuel, or is it pointless and I just need to ride more to get used to the longer distances.
You are eating 150 an hour and can still ride for 5 hours? I am in the 300+ calorie per hour group on my long workouts. A gel about every 30-40 minutes and a sports drink. I would definitely try more fuel.
A good starting point for nutrition and hydration guidance is Hammer's "The Endurance Athlete's Guide to Success" available free as a pdf on their website -- or you can get a free bound copy with your first order, or pay $4.95. It sets out Hammer's "Replacement vs Replenishment" philosophy and provides basic recommendations that can provide you with a good point of departure as you determine your body's needs and tolerations.
Joe is spot on: you probably need more calories early on. But jumping up to 600-800 may be too much. Also, keep in mind that hydration and sodium/electrolyte replenishment are as important as calories.
And it's always good to finish off with a trip to IHOP to get the Nutella Crepe Breakfast.... Mmmmmmm Yummy.
mmmmm.....nutella. Thanks for the replies.
The harder you're working, the fewer calories your body will be able to take in. If you're running the Army 10-miler, you' don't want to take in 4 gels, but if you're biking for five hours, that intake rate may be about right. For long rides, 250-400 calories is a good range, depending on what you're eating/drinking and you're body's ability to multi-task. Hammer's guide is good, but experiment with different products to figure out what combo works best for you.
Honestly, I've never really had stomach issues at a race or in training other than an IM when I started vomiting at mile 26 on the run. It is just that without fail, around 70 to 90 miles into my rides I start feeling pretty bonky, and I'm not sure if it is just a matter of inadequate endurance or lack of nutrition. I don't want to start stuffing my face in training without a good reason to. One gel per hour with some Gu2O after the first 60 minutes of riding has been working well for me for up to 60 miles or so, but beyond that, not so much.
It sounds like you're running your gas tank to empty, and trying to fill it all at once. Next ride, I would suggest taking a gel every 45 min. instead of 60 min., and see how it goes. It shouldn't be that big of an adjustment, but should get you further along. If you're riding 70-90 miles for long training rides, endurance isn't the x-factor. Remember, with shorter rides, you don't need to take in as much because you can burn off energy stores. In long rides, that reserve gets used up.
Bonking on long rides is usually not a matter of endurance if you are experienced at distance.
Recommend seeing a nutritionist, like Rebecca who has helped several triathletes with endurance training needs. http://www.expertnutrition.net/
The Hammer pamphlet is also a good source.
Like Joe and Gary said, you are more on track at the higher calorie count than at 150 - also electrolytes. You may be at 400 calories, which if achieved through Gu's and Gatorade may have 300 mg of sodium, but you may be have an 800 mg/hr sodium sweat rate. Then you may consider supplementing with Endurolytes or similar, which have sodium, plus potassium, calcium, magnesium, and chloride. A nutritionist can help you dial into your needs.
A go-lean on the bike philosophy could be bad unless you are super efficient. The bike is your primary place to ensure nutrition. Remember you are also fueling for the run. Train nutrition not to be making the bike, but to be preparing for the run.
+1 what Simon and Gary said about sodium - 4-5 hrs of cycling means sweating a lot, and it doesn't sound like you're replacing the salt with your current nutrition plan.
I have been using Infinit (www.infinitnutrition.us) for the last couple years. The Ironman formula has about 275 calories and includes electrolytes, sodium, etc. needed to keep you going. You can customize the mix based on your individual needs.
For longer rides or races, I carry a concentrated mix of Infinit and squirt some of the concentrate into my JetStream aero bottle & then add water from the aid staions.