I first started making my own running fuel because I can’t afford to fuel the amount of running I do with the name-brand stuff. With the amount of carbs in a typical gel pack, you need 2-3 an hour. I run an hour 3-5 days a week, and long training runs are from 2.5 to 6 hours depending on whether they’re road or trail. Cheap gels like Gu are $1.60 each with 23 carb grams ($0.07 per carb). Primo brands like Maurten 100 are $4 with 25 carb grams ($0.16 per carb). An affordable option of packaged gel that I use is Carbs Fuel at $2 with 50 carb grams ($0.04 per carb) and I splurge on SiS Go Isotonic at $1.89 with 22 carb grams ($0.09 per carb) for races.

Even if I only use gels on long runs and I use Carbs Fuel at 2 gels per hour, I’m looking at $10-$24 a week just on fueling my long run. $70-$80 a month on gels just for long runs is crazy.

My first foray into making my own fuel involved throwing animal crackers, protein powder, beet powder, and maybe something else into a food processor. It wasn’t pretty, and it didn’t taste wonderful after a couple of hours. It also got hard after a few hours, and the first time I used it in a 100-miler, I couldn’t get it to squeeze out of my reusable baby food containers by mile 80. Lesson learned.

My next iteration involved research on what the body can digest/process during activity. I learned about different sugars and types of carbohydrates (tapioca maltodextrin and cyclic dextrin), along with when and how much protein to include for longer efforts. I learned leucine is a better choice than whey protein, but (for me) that it causes a bathroom stop if used over 2-3 hours.

My current gel recipe is a combination of the above and a recipe from Jim Downing. This recipe gives me no gastric distress and supports higher carb intake, according to latest performance fueling approaches. I used it on my last 24-hour effort in which I covered 108 miles and didn’t need to go #2 for the entire event. Win win.

• 48 grams maltodextrin (I split 50/50 between tapioca maltodextrin and cyclic dextrin)
• 32 grams fructose
• 1.25 grams pectin
• 1 gram sodium alginate
• .5 scoop organic lime powder (for flavor)
• 2 grams citric acid per 100 grams of the above ingredients

Those ingredients provide 74 grams of highly-available carbs. After mixing the dry ingredients, I heat the same weight of water (50/50 ratio) in a saucepan. Jim’s recipe above calls for a 60/40 ratio, but I find that too thick for my liking. Before the water comes to a boil, slowly add the dry ingredients while stirring – preferably with a whisk. After the dry ingredients are fully mixed in, heat for another 1-2 minutes, stirring occasionally to keep from boiling over. Then remove from heat and let cool to, at least, below 140˙F before pouring into a reusable flask.

A batch of this will easily fit into a 150ml Hydrapak soft flask. I prefer the tops without the silicone valve, to keep flow quicker. I haven’t tested how long you can leave it out before going bad, but I had containers of this gel in my bag over that 24-hour event and I didn’t have any issues with it – going bad or causing gut issues. However, I still wouldn’t trust that on a hot day with sun exposure.

My current fueling strategy involves a batch of this per hour, paired with an electrolyte hydration mix to bring me up to 120-140 grams of carbs per hour. I cycle between using Tailwind, Hammer HEED, and Carbs Fuel.