Training & Nutrition - Calorie/Fluid/Sodium Absorption Rates for 240 lb Cyclist

Bikeforums.net is a forum about nothing but bikes. Our community can help you find information about hard-to-find and localized information like bicycle tours, specialties like where in your area to have your recumbent bike serviced, or what are the best bicycle tires and seats for the activities you use your bike for.




Tall Cool One
01-18-12, 06:52 AM
I am a 6' 7" 240 lb rider and I have been doing a lot of reading on Hammer Nutrition's website about how much nutrition to take in each hour. I am preparing for Ride Across Indiana (160 miles) in July and want to nail down my nutrition for the event.

I estimate that the ride will take me about 9 hours including rest stop time.

According to Hammer, the following substances have the below absorption rates

Loss vs. Assimilation
What can your body really handle?
SUBSTANCE RATE LOSS/hr______________ASSIMILATION RATE
Fluids (ml) 1000-3000 (30-90 oz)________500-830 (17-28 oz)
Sodium (mg) 2000____________________ 500-700
Calories 700-900 _____________________240-280

Below are the corresponding replenishment values that we have observed for the averagesize endurance athlete (160-165 lbs/72.5-75 kg) who is fit and acclimatized (+/-5%):

SUBSTANCE IDEAL REPLENISHMENT
Fluids 20-33%
Sodium 20-35%
Fuels (Calories) 30-40%

My question is....Does my 240 lb body absorb more fluid/sodium/calories than the "average" 160 lb endurance athlete? I know I burn more calories, go through more fluid, and I assume I go through more sodium than the "average" endurance athlete.


Carbonfiberboy
01-18-12, 10:52 AM
One can't nail this down, since every ride will be a little different, depending on training, recent history, course profile, winds, and temperature. All this stuff affects both loss and assimilation rates. By July, you'll have it figured out as you train. Both loss and assimilation rates are trainable, BTW.

Tall Cool One
01-18-12, 11:41 AM
...Both loss and assimilation rates are trainable, BTW.

How can you train your body to lose less fluid/sodium/ burncalories or train your body to assimilate more fluid/sodium/calories?

I'm curious.


Carbonfiberboy
01-18-12, 12:35 PM
You can get your calorie burn down by training to be more efficient at your chosen speed, mostly by acquiring the flexibility and strength to hold a more aero position.

Hammer has a lot to say about sodium balance that I don't remember, but I think sodium loss is trainable by hot weather training, fluid loss the same.

Assimilation is more straightforward. Basically, you pummel your stomach with as much food and fluid as it can handle. Over time, it responds by becoming able to move more stuff across the stomach wall.

Basically, this is how RAAM and other LD competitors manage what would seem by casual calculation to be impossible feats. More information at http://www.ultracycling.com/

Your body is a chemical machine that responds to training. All of it.

Tall Cool One
01-18-12, 06:15 PM
....Assimilation is more straightforward. Basically, you pummel your stomach with as much food and fluid as it can handle. Over time, it responds by becoming able to move more stuff across the stomach wall...

I love this kind of training. I have been training this way for decades. Trust me, I have moved a lot of nutrients through my stomach wall!!!!!!:lol:

But seriously, thanks for the input. :thumb:(p.s. Please don't take my flip responses as being unappreciative.)