Iteration 1

• Started/Inspired by this Video Stop Wasting $$$ on Fancy Running Gels: Make Your Own at Home!
• Bought:
  • Maltodextrin, 2.5 kg, 13€
  • Fructose: 1kg, 9 €
  • Electrolytes: 200g, 9€
  • Pektin f. Marmelade Konfitüre: 100g 9€
  • Containers: Reusable Shampoo Bottles: 4 pieces, 10€
• Used Recipe (from Video):
  • 200 g Maltodextrin
  • 100 g Fructose
  • 200 ml of boiling water
  • half Tea-spoon of Pektin
  • A bit of Electrolytes (have to calculate how much I need)
  • Lemon acidifier for taste

Observations:

• Yields 3.5 100 ml bottles

Calculations

• Maltrodextrin is 95% carbs

• I assume fructose is 100% carbs

• I assume one teaspoon is 5 grams, so 2.5 grams Pektin was used

• I assume 1 carb has 4 calories

• I define sugar as either Maltodextrin or Fructose

• I assume that 30-60 g of carbs is a good target, 45 g

• 300 g sugar was used

• Resulted in 350 ml of gel

• 86 g of sugar per 100 ml

• 343 ckal per 100 ml

• 500 g input, 350 ml output

• 142 g gel for 100 ml gel

• Gel is 67% carbs (see recipe)

• 142 g/100ml x 4 ckal/carb x 0.67 = 375 ~ 343 ckal/100ml

• I used 300 g sugar for 350 ml. Factor 1.167

• I need 30-60 g of sugar per hour.

• To get 30 g of sugar, I need 30x1.167=35g of gel

• To get 60 g or sugar, I need 60x1.167=70g of gel

• 100 ml gel has 142 g, so factor is 0.7, 1.42 in the other direction

• To get 35 g of gel, I need 35x1.42 = 50 ml, nice!

• To get 70 g of gel, I need 100 ml

• -> I need 50 ml to 100 ml of gel per hour

Cost:

• To get 350 ml of gel, I used 200 g Maltodextrin, 100 g Fructose, 2.5 g Pektin, a bit of Electrolytes and something for taste
• 200 g Maltodextrin is 200 g / 2500 g x 12.50 € ~= 1€
• 100 g Fuctose is 100 g / 1000 g x 10 € ~= 1 €
• Pektin is 2.5 / 100 x 10 ~= 0.25 €
• I assume Electrolytes is ~= 50€
• I assume Taste is ~= 2.5€
• So the total cost for 350 g of gel was 1+1+0.25+0.5+0.25 ~= 3€
• 100 ml has 60 carbs
• 60 carbs of gel costs 3 / 3.5 = 0.86 €
• 30 carbs of gel = 0.43 €
• 45 carbs = 0.65 €
• If I fuel 45 g of carbs per hour and run 4-5 hours:
• 2.6€ -3.25€ per Marathon

Experience:

• TBD

Problems:

• Bubbles

Open Questions:

• Cheaper Pektin
• How much Electrolytes?
• Should I add sodium?
• Optimize amount of Pektin
• Shelf-Life in Fridge?
• Caffein?

Ideas:

• Coke instead of water for Taste

How much Electrolytes?

The Salt Tablets I am using have these ingredients:

Jeff Pellentier:

• 250-350 ckal per hour
• Up to 2 per hour (only if it is hot)

So, 1 per hour in the gel seems fine, if it is hot, I can supplement using tablets.

The powder I bought has these ingredients:

I want:

• 22 mg Calcium = 100 / 6375 x 22 = 0.35 g
• 11 mg Magnesium = 100 / 3125 x 11 = 0.35 g
• 349 mg Cloride = 100 / 6375 x 350 = 5.5 g
• 215 mg Sodium = inf
• 65 mg Potassium (=Kalium) = 100 / 5825 x 63 = 1.1 g

Ok, regarding Calcium and Magnesium, I would want to have 0.35 g of the powder per hour, regarding cloride, I would need 5.5 and Potassium 1.1 g. This is a problem, I need to add manually:

• Cloride: 300 mg
• Sodium: 215 mg
• Potassium: 40 mg

As you see in the table of the salt tablets, you get cloride from sodium cloride and potassium cloride.

As you see in the table of the salt tablets, you get cloride oride from sodium coloride and potassium cloride.

Conclusion: Per 100g of gel, add:

• 0.35 g of electrolyte mix
• 300 mg worth of cloride
• 215 mg worth of sodium
• 40 mg worth of possasium

The recipe above (300g sugar) yielded 350 ml, thus we need to add:

• 1.15 g of electrolyte mix
• 1050 mg worth of cloride
• 725 mg worth of sodium
• 140 mg worth of potassium

This will get kind of hard as a teaspoon has 5 g, so a fifth of a teaspoon of electrolyte mix.

Regarding chloride and potassium: I guess I just throw salt to it for now and add 3 gram of salt so for now

The recipe above (300g sugar) yielded 350 ml, thus we need to add:

• 1.15 g of electrolyte mix
• 3 g of salt, which include potassium

(5-6 grams of salt are recommended per day, so this is not crazy)

Iteration 2

Basically the first iteration, but with Improved Electrolytes

• Used Recipe (from Video):
  • 200 g Maltodextrin
  • 100 g Fructose
  • 200 ml of boiling water or some soda (light?)
  • half Tea-spoon of Pektin
  • 1.15 g of electrolyte mix
  • 3 g of salt
  • Lemon acidifier for taste (or the soda for taste)

This yields 350 ml of Gel, each 100 ml contains 60g of carbs, where I consume 30-60 g of carbs per hour. 100 ml are worth one salt tablet.