Saturday: Pro Fuel and Hydration app: User inquiries

Very much planned and in development! This is a feature I look forward to, because I often find myself in the same situation.

You’re thinking about all the right things:

  • Timing of pre-workout meal
  • Content of the pre-workout meal
  • Fueling needed immediately pre-race, instead of during, because you’re right, consuming anything during an all-out 5k race is not optimal.

Share the app in some closed social media groups and I’ll put 100% of earnings from new subscribers towards poaching another developer from their day job.

(They’re all athletes, and all have full-time work elsewhere).

Here’s a hack that helps for now: Consume the recommended amounts 10-30 minutes pre-race. Listen to your intuition about gut comfort if you’re going all-in in the race :slight_smile:


Feature Request

It would be fantastic to have the ability to input and customize my FTP within the app. This would allow for a more personalized and accurate carbohydrate intake recommendation, taking into account individual training intensity and energy demands.




What is the objection to always fueling with 90g+ an hour? If your goal is performance and recovery, outside of a recovery ride you’ll always burn more calories than you consume. Unless of course your FTP is exceptionally low.

I used to fluctuate my fueling based on intensity and duration. Then I realized I could just use the same fueling strategy on every ride/workout and maximize performance and recovery, not to mention train the gut. I haven’t found a down side.

For about a year now I’ve used about 100g hour every time I get on the bike. The only exception is my races where I try to push up to 120g per hour (less for very hot/humid conditions). The only factor that changes is how much plain water I bring based on my expected sweat rate.

Smaller people and people who are just getting into the sport are not exceptional cases. Heck I wouldn’t call my own FTP “exceptionally low” – puts me smack in the middle of the bell curve for my age and gender – but 100g of the mix I use would be roughly what I burn during my favorite Z2 session, or this family of Tempo sessions.

Optimal fueling doesn’t mean “fuel until your gut complains”, it means “fuel until there’s no longer a performance or recovery benefit”. If I can get the same benefit out of 60g/hour that I’d get out of 90g+ then I’ll save myself the cash, heh.


And the calories. And the complication. And the potential dental issues.

I’d bet that you train more, harder, or at a higher absolute power than the average person. If those things are true, then you may be right, that there is very little to no downside with always hitting >100g/hr. Many pro athletes fall into this category.

Just be aware of future performance benefits caused by today’s fueling, not as a result of improved recovery. What I mean is: gut adaptation and systemic physiological adaptation in response to higher carbs, allowing better use of higher carbs in the future. It takes sometimes going slightly higher than what is necessary to perfectly optimize performance today, to max out adaptations for tomorrow.

Sugar is an incredibly simple and virtually free (by comparison to a gel) way to add really high-value calories to your fuel mix. Might be the cheapest kcal I consume all day! That said, I prefer less total carbs during shorter and easier rides because I like to eat more of my kcal, so I’ll go much lower than 60g/hr for easy stuff under an hour. I have my app satiety setting set to the bottom option so that it handles that for me.

1 Like

A few weeks ago i did a ten hour ride and plugged the info into the app. It prescribed too much water(over 1L per hour) as i didnt want to make that many stops so didnt follow the plan and i drank maybe 700ml an hout…man struggled super bad 6 hours in and alolmkst quit This week i did an 9 hour ride and followed saturdays instructions to a tee. Over a liter an hour and 1500 of sodium per hour. And i felt amazing. I was amazed i was still holdikg z2 power in z2 hr at hour 8 and feeling great. Just wanted to say thank you


That’s awesome! Really appreciate you popping on here to share your experience. I think Saturday is going to need to strike up a partnership with a hydration pack and bottle company soon. :wink:


Hi @Dr_Alex_Harrison, loving the app and UI experience so far! One question more around execution than the app itself, when you get your recipe, is the idea to dilute the salts/sugars evenly across however many bottles are needed and drink continuously, or is there a benefit to having some salts-only bottles to chase the nectar? I’ve experienced gut distress before and ticked that box in the app, but wanted to make sure especially around longer rides, as I’ve never been brave enough to only drink carb mix for a whole ride! Sorry for the rambly text, and thank you for your input!

Question: Saturday is recommending that I drink 920 ml/hr during my long runs (currently 2.5-3.0 hours). This is about the same fluid intake it recommended for cycling.

I’ve managed to drink about half of that and feel like my stomach is full of liquid sloshing around. Is the app recommending too much liquid by mistake? Or do I just need to keep running and drinking and over time (how much time?) I’ll become able to drink more per hour?

@Dr_Alex_Harrison One thing I haven’t seen discussed in this thread or your others (that I can recall) is post workout. Thoughts on this, whether it should be just a normally planned meal, or a recovery drink of some sort? I imagine if the latter, a mix of protein powder and Gatorade/sugar would suffice.


Correct. But probably not necessary unless between workouts in a 2-a-day scenario.

Yes, in 99% of cases. ^^^ It should include protein and carbs, and whatever else you like, intuitively. (Fat, fiber, fluid, micronutrients, etc, all in alignment with your personal values and your overall nutrition approach). Avoid alcohol if you care about performance.

It’s far more common for folks to overthink and be overly specific with their post-workout concoctions than to overthink their intra-workout/race mixes.

Separating is a matter of preference. And dental health. I prefer all sodium and carbs in one or two bottles so that I can always have a fresh water bottle to chase fuel mix with. Chasing with water probably helps reduce dental risk.

We’ll implement an option that allows lower fluid consumption during running soon. Your gut will adapt, but not a lot. If feeling sloshy, consider notching down the sweat rate slider one or two notches for your runs and see how you handle that.


That’s exactly what I tried yesterday: dragged the sweat slider down to 3. The app had originally said to make 2.67L+240g, and changed to 2.57L+240g. Seems like a small change for a 2.7-hour run, but it was cool and humid so perhaps that mattered. This was for a fasted 18km (and new distance PB, yay).

I made 2.2L+240g of mix (~15% less), drank 0.7L a half-hour before starting and as much as I could (0.9L) during the run, feeling “sloshy” most of the way. Still surprised that I was able to drink less than a liter during the actual 2.7 hours of running… how long does it take to absorb the initial 0.7L???

So, 1.6L total in 2.7 hours = 590ml/hr, 30% below Saturday’s recommendation for sweat rate 3. On the plus side, I got 175g of carbs in me which is an improvement. I felt better than I had expected and was able to maintain my 9:00/km training pace all the way.

Looking ahead to the Staten Island Half in two weeks, I figure the most important thing is to get all my carbs (still missed out on 75g yesterday) while hopefully drinking a little more per hour during the run. If Saturday says 2.92L+283g, I would think 2.0L total (0.7L before, 1.3L during).

Expected race time is 3.1 hours, so this is 79 g/hr of carbs and 645 ml/hr of water. Does that sound reasonable? I remember you saying that insufficient hydration was a large cause of GI distress and performance issues, so I worry… but OTOH I’m planning to drink almost 10% more water per hour than yesterday and I’m not sure that MORE water is realistic.

What do you think?