Need to Supplement Maurten 360 or SiS Beta Fuel with Water?

Any thoughts on whether just drinking Maurten 360 (or the SiS version) would be sufficient on an epic ride, without drinking just water from a separate bottle?

From Nate’s experience at Leadville and from my own experience using Tailwind, it seems that simply drinking Maurten or TW may lead to dehydration, especially on warm days. I remember Coach Chad’s comment on the podcast about how Nate might have had difficulty with the warm Maurten perhaps due to its caloric density toward the end of the LV race.

This makes me think that it may not be good to rely soley on Maurten or TW for both nutrition and hydration and that it may be advisable to have a water bottle to provide some additional hydration.

Any thoughts on this matter?


If it is cold enough I think you “could” get a way with SIS Beta Fuel only but in general I don’t think it is enough fluids.

Note: I know that I am a heavy sweater.

I just did a 70 Mile 5000 Foot Aquabike at the Multi-Sport Worlds with an average temperature of 68 degrees. I completed the bike course in 3:31 and my nutrition plan was:
2 Bottles of Beta Fuel plus 2 Nuun Tabs in my 30oz front water bottle
6 Powerbar Hydro Gels in 500ml water bottle, topped up with water

While on the course I filled up my front bottle twice with no calorie electrolyte drink that they had on the course and I downed half an electrolyte bottle while going through another aid station. If it had been any hotter I would have needed more water/electrolyte but my calorie consumption was just where I needed it.

I would look at your calorie requirements and your hydration requirements as two separate entities. Your calorie requirements are based off of your duration, intensity, and tolerance where as your hydration requirements are based on duration, intensity, salt loss, and temperature.

For a 2 hour ride at 105F I could go through 6-8 electrolyte bottles (i’ve done it) but only need 200-300 calories consumed. Yet for a 2 hour ride at 50F I could go through 1 electrolyte bottle and still need 200-300 calories. Or I could go for a 2 hour ride, need 600 calories and 3 bottles in something like 70F weather if I am going all out.

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This. Think of the SIS beta fuel packet as how much you can consume in 1 hour. You can dissolve this in 1 bottle if that is your hydration need, or you can dissolve it in 2 if you need 2 bottles/hour. Or you can put it in 1 bottle and have 1 bottle of plain water or additional electrolyte if you know your sweat is higher conc

I’m doing some endurance MTB races, and it seems to me that for long hilly races, having nutrition delivered in fluid form exacts a pretty heavy weight penalty. Two Scratch energy bars is far lighter than a 500ml bottle of Maurten 320 mix while providing a very comparable amount of carbs.

I guess the benefit of nutrition in fluid form is the convenience in eating and perhaps quicker digestion and absorption.

Do you not carry water during the races? The way I look at it is powder weighs less/cal and is cheaper than any bars.

I keep my hydration separate from my nutrition. Allows for flexibility to hydrate more/less depending on how im feeling.

I think this is very true for long duration races, where if you get your hydration/nutrition mix a little wrong, it compounds over time.

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This spring I have been experimenting with the SIS Beta Fuel and the following has worked so far for endurance events lasting 3 1/2 to 5 hours:

750 ml bottle w/1 sachet of Beta Fuel every 90 minutes and
1 SIS Isotonic Energy Gel every 60 minutes

I carry two 750 ml bottles and hence can go ~3 hrs before replenishing liquids.

I’ll test this next week in a century with the goal of stopping only once to refill/remix both bottles. My only concern is that the temps are looking like they will be 10-20 degrees higher than what I have been training in all winter/spring, and hence I may find myself drinking more as I sweat more.

Just did a 6-hr mtb race with temps in high 50s…Had to stop drinking Maurten because I was peeing every 50-min lap so my carb intake schedule fell behind . . . ummmm did somebody say to separate nutrition/hydration? :smile:. Started to take more gels and a bit of water from a bottle. I distinctly remember a similar situation in another race - a 50 miler - where the temps were cool and taking 500ml of Tailwind every hour made me pee every hour.

I just realized why I never really had to pee that much during equivalent training rides where I wake up, hop on the bike and then start riding…All of these races, I’m downing a bottle of water or some mix while driving to the race.

Man, writing this out sure has helped things.

Now I got to think about drinking a bottle of water or mix before doing training rides to simulate race conditions and figure out a separate hydration/nutrition plan that won’t make me pee so much!

And it’s worse if it’s the other way around I.e. if it’s hot and you’re thirsty and only have maurten to drink… when all you want is water.