there are probably a few answers to this, 1- slow release carbs tend to be large molecules, that means they have a lower osmotic pressure than say smaller molecules like glucose and fructose and that means you tend to have less stomach upset. 2- in most cases people do not drink every 10 minutes and definitely do not replace the carbs that fast so some different carb timing may help over the long haul.

I suspect there is research out there on this that might make it more clear and of course the brain trust of Slowtwitch.

If referring to claims like from UCAN, i would think if you're trying to maximize uptake and can continue to eat/drink the whole time then it will be detrimental as the long change resistant starches will slow gastric emptying. For maltodextrin based products that simply claim complex carbs instead of sugar, those are actually absorbed at a rate similar or higher than glucose so should not be considered slow release

Yea I was referring to UCAN and similar products that use starches. I read that maltodextrin uses the same metabolic processes as glucose and are only limited to 1g/min

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IG - @ryanppax
http://www.geluminati.com
Use code ST5 for $5 off your order

UCAN actually clears the stomach way faster than simple sugar or maltodextrin based sports nutrition due to the low osmolality of SuperStarch. The molecular weight of SuperStarch is approximately 600,000 (simple sugars are 180, maltodextrin is 500) which means that it releases energy at a steady rate as it's broken down, and also that there are fewer molecules in a given volume (lower osmolality) so it exits the stomach quickly and then "seeps" into the system through the intestines. Dr. Krista Austin speaks well to that feature in this podcast on Run To The Top: https://runnersconnect.libsyn.com/...he-ucan-story-part-2

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Matthew J Bach
Director - Triathlon Business
The UCAN Company
matthew.bach@ucanco.com

Once the intestines are saturated then gastric emptying will slow regardless of osmolality if breakdown is slow via feedback loop with CCK, GLP etc. If your goal is to maximize uptake to replenish glycogen maximally this is a bad thing. If you look at their studies, they give a single bolus of 75g of UCAN and measure over ~7 hours the uptake. Whereas we already know we can take up to 90g/hour via glucose/malto and fructose to maximize performance. So if working at super low subthreshold intensities where you don't want to carry anything, UCAN might be useful, otherwise fast absorbing carbs taken regularly is where its at

No science to back it up. I used UCAN 20 minutes before the swim in my last Ironman but used Infinit from there until half way though the run. My thinking was to avoid an insulin spike right before starting but to have some slow release carbs in the system the whole swim. Made sense to me which probably means it's a bad idea.

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_____________________________
David Gramer

I used Ucan for a few seasons racing IM and it is good that you seem to have constant energy where as with faster release carbs you can get the higher and lower energy periods. I stopped using it because it doesn't mix well in your bottles and I found a product I like better that works for me.

I'm also curious how uptake could be affected by Imodium. Ucan or glucose. Anyone know?

I raced with a pre race Immodium yesterday and for the first time I didn't nearly shit myself on the run so I plan to continue to use it. The drug says it slows small intestine movement. What exactly does that mean?

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IG - @ryanppax
http://www.geluminati.com
Use code ST5 for $5 off your order

The science is above my head so I'm relying on professionals to help me out. Dr. Krista Austin, sports nutritionist to the pros (Meb, Tim O'Donnell, Dathan Ritzenhein, Kara Goucher, to name a few) and who has worked with the U.S. Military, has this to say:

Superstarch can be used as a stand alone product or in conjunction with other forms of energy, including high glycemic carbohydrates. At present, the consensus among sport professionals is that carbohydrate use for training purposes can be in the form of low or high glycemic carbohydrates and that multiple forms of transportable carbohydrates should be used when desiring to achieve the maximal amount of carbohydrate for prolonged endurance events; however the satutation point of maximal intake is very individual. The Superstarch assists athletes in achieving their desired carbohydrate intake because the osmolality is so low which allows it to empty from the stomach more rapidly. This can be a limiter for many athletes when using forms of carbohydrate with a higher osmolality. The number of GLUT1 and GLUT5 transporters available do determine transport of carbohydrate across the plasma membrane; however the rate of uptake is dependent upon the rate of glucose or fructose release from the carbohydrate consumed. The benefit of the Superstarch is that is is broken down more slowly. This should help the transporters regulate more easily the transport across the plasma membrane and in turn support the greatest amount of carbohydrate possible when combined with high glycemic carbohydrates without GI distress. Note, it would only be recommended that 30 grams of Superstarch be used per hour. The remaining carbohydrate could come from high glycemic sources.

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Matthew J Bach
Director - Triathlon Business
The UCAN Company
matthew.bach@ucanco.com

You can't fuel during the ironman swim, so before the swim is the only place where I've found it to be useful. After you get out on the bike and run, there's lots of fuels around so you go back to high-frequency schedule.

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Zen and the Art of Triathlon. Strava Workout Log
Interviews with Chris McCormack, Helle Frederikson, Angela Naeth, and many more.
http://www.zentriathlon.com

Do you do a fast carb and slow carb before the swim?

What does your timing look like please?

I had the same experience. I loved the energy and that I never felt "hungry" during long events. But sometimes it would create this weird glob at the bottom of a bottle that no amount of shaking could break up. I'd sit there on the bike seeing 70% of my nutrition clumped at the bottom of the bottle with no ability to break it loose.

eventually the logistics of it pushed me back to First Endurance.

You can buy steel "shaker balls" to put in your bottles and it'll stir up the stuff better. I bought a bunch of them years ago and love them. I just leave them in the bottles forever. Here's some on Amazon.

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Zen and the Art of Triathlon. Strava Workout Log
Interviews with Chris McCormack, Helle Frederikson, Angela Naeth, and many more.
http://www.zentriathlon.com

Definitely try in in your swim workouts first to see how it works for you. But yeah, Drink the ucan with about 30 to 40 minutes before you start. Then sip on a gel mixed into 10 oz of water while you wait, starting at about 20 minutes before go time. Spread it out over 20 minutes so you don't spike yourself. Toss the bottle in a trash bin or hand it off to a friend before you hit the water.

The wire balls work well, but there are other things you can do too, to make sure the UCAN stays mixed...
1.) Do 2/3 water, then UCAN, shake then top off with water and shake again
2.) Mix the night before and stick it in the fridge. Dissolves better
3.) Always water first, then powder (I'm sure you're doing this right, but you'd be amazed how many people I run into that aren't!)

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Matthew J Bach
Director - Triathlon Business
The UCAN Company
matthew.bach@ucanco.com

I eat a bunch of carbs the day before and then wake up at 3am or whenever race day and crack a sugar free Red Bull, take a 5hr energy, and then another dose of caffeine in my preworkout before the swim. Sometimes a Starbucks doubleshot too. I take my preworkout (Nitraflex) 30min before swim start and then sip on Vita Coco Pineapple Coconut water. The Nitraflex helps for me to get real excited about racing but also the massive caffeine load makes my mind do cartwheels with my race plan and checklist.

It’s my routine. Last 70.3 I carb loaded Popeyes on Saturday with a large rice and beans, large dirty rice, large Mac and cheese, large green beans, and large cole slaw. It worked perfectly (4:48 PR). Previously I’ve loaded up Saturday with McDonalds cheeseburgers (x10) and breakfast muffins. I don’t exactly try to over eat or anything I just listen to my body and try not to feel hungry and also let anxiety take control and eat away the nerves race weekend. My bowel movement is precise with the caffeine race morning and feel that I can pull from recent fat stores that I lined up from Saturday. I burn 4000-6000 cal per day in training and about 6000-7000 calories for a 70.3 so it has been enough.

Those are my slow release carbs.... I guess - lol

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https://www.strava.com/...tes/zachary_mckinney

What Pro cyclists eat for breakfast:

https://www.youtube.com/watch?v=38Jt9BL2XAo

This was made at the Giro D'Italia (3 week race) and you'll notice that it's REAL food.

What Pro Cyclists eat for lunch:

https://www.youtube.com/watch?v=0MFm1iSlP8c

Insight with the EF nutritionist:

https://www.youtube.com/watch?v=2iriejQTgF0

I appreciate the irony of your username and loading yourself up race weekend with an abundance of junk food. with your pre-race routine of all that caffeine I'm picturing your smashing metal garbage cans with your head to get yourself psyched up for the race. lol But if it works for you that's great. My system would revolt with that intake.

I can echo this. I used UCAN for 2 seasons of IM racing. I liked it because it wasn't too sweet, gave constant energy, and actually made me feel like I had some "food" in my stomach 7 hours into a race.

However.... the logistics around it were a pain. It would go bad after 4-5 hours so you really couldn't pre-mix things for special needs. Half the time the powder would cake at the bottom of a bottle and it simply wouldn't come loose no matter how much you shook it. I eventually got the same result with another nutrition source and just eating something solid a few hours into the bike.

haha yeah

I don't smash the red bull cans on my head or garbage cans - I'm just silently amped up - I'm an introvert....

I looooooveee caffeine though ----- I have a lot of 100mg expresso shots during the race..... I train with lots of food and caffeine - I burn so many calories that I just need a lot of fuel and 'nitrous'

If its really hot outside though I limit my caffeine if I'm going to sweat a ton and typically don't have any on the run if so, as I don't crave it anymore.

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https://www.strava.com/...tes/zachary_mckinney

i use ucan in concentrated bottles at him and im distances. i use an immersion blender and never have an issue with it mixing. love it! i mix one concentrated bottle per loop.

My issue was that I didn't want nutrition that needed a blender to work.