Andrew Creer

Professor of Exercise Science at THE Utah Valley University…Father of @t_creer54

[Stuart Phillips (he/him) @mackinprof]

https://t.co/Ypv7BiW1zG

[Stuart Phillips (he/him) @mackinprof]

https://t.co/ljeraSGVQS

[Stuart Phillips (he/him) @mackinprof]

Tim, with respect, several of these don't hold up. Going through them.

1/ The "no RCT longer than 4 weeks" criterion is convenient but doesn't dissolve the contrary evidence. Burke's Supernova series (J Physiol 2017, J Physiol 2021, MSSE 2021) consistently showed impaired economy and race performance in elite athletes at 3 to 3.5 weeks. Your reply is that longer adaptation would reverse this. That is itself an unproven hypothesis. You are requiring receding goalposts, which is exactly the move you accuse the field of making.

2/ "Only elite athletes" cuts both ways. Your foundational RCTs are in recreational athletes doing capacity tests. The 5 to 7% ATP-yield-per-litre-O2 deficit (Krogh and Lindhard 1920, which you cite) shows up only at intensities that recreational athletes cannot sustain. Dismissing elite data while resting your case on recreational time-to-exhaustion is the double standard, not the rule against it.

3/ The SGP/LGP framing is a useful lens. The 16 lines of evidence include real contributions. They also include retrospective reinterpretations of studies whose original authors drew the opposite conclusion, rat models you criticize when others lean on them, and the "88%" claim that arithmetically gives 84% in your own Table 8 (105/125). I went through the Zenodo file line by line. The pattern is real, the framing is generous.

4/ The "cake problem" is not a strawman. Volek, Noakes and Phinney 2015 (Eur J Sport Sci) argued fat adaptation eliminates CHO dependence. If 10 to 20 g/h carbs during exercise is now required, that founding claim has collapsed. Ketones do not rescue it: Whitfield et al 2021 (MSSE 53:776-784) showed acute ketone ester plus LCHF impaired race walk performance.

5/ The biochemistry. Less ATP per litre O2 from fat is settled. At the oxidative ceiling that determines elite endurance pace, that deficit shows up as lost speed. None of the 16 lines of evidence engage with this directly. They route around it.

6/ On agenda. You were a high-CHO advocate for 35 years before reversing. The same charge of motivated reasoning applies symmetrically. I have no books to sell, no nutrition company shares, and no foundation downstream of the conclusion.

7/ "Bottom line" is a summary, not a fixed verdict. Carbs yield more ATP per litre O2. Fat oxidation tops out around 2 g/min even after weeks of keto adaptation. Elite marathon pace demands more energy per minute than fat can supply. Every elite marathoner, Kipchoge included, ingests 80 to 100+ g/h of carbs during competition. When the evidence changes I will update. Until then, carbs win at the top end. That is a conclusion, not an advertisement.

Mechanistic mechanisms for the glycogen-fatigue link that have nothing to do with rigor are well documented and you know this: SR Ca2+ release (Ørtenblad et al 2011, J Physiol 589:711; Gejl et al 2014, MSSE 46:496), subcellular pool depletion (Jensen et al 2020, J Physiol 598:4271), and downregulated PDH and glycogenolysis after fat adaptation (Stellingwerff et al 2006, AJP-EM 290:E380). The TAT you keep dismantling is not the position the field holds.

Honestly, thanks for your diatribe. But it's just more of the same.

[Louise Burke @LouiseMaryBurke]

These aren’t the highest rates of fat oxidation ever measured in a human - elite racewalkers who adapted to a keto diet for 6 days or 3.5 weeks showed higher rates - some at 2 g/min. But they raced at a slower speed when asked to perform in a real life race. You can’t outrun the stoichiometry of fuel production. Carbs produce more ATP per litre of oxygen than fat.

[Tyler Creer @t_creer54]

Hey friends!

I have just started as a sales rep for Real Salt Lake and the Utah Royals!

If you’re interested in season tickets for 2026 or if you have other questions about either club, hit me up. Let’s talk. I’d love to help you come and watch some exciting soccer next year!

[Andrew Creer @AndrewCreer]

@UVUwvb Take the hammer back!

[Andrew Creer @AndrewCreer]

@t_creer54 @Highland_Ag Truth

[Andrew Creer @AndrewCreer]

@t_creer54 Me too buddy

[Alex Hutchinson @sweatscience]

New calorie data (from double labeled water) on 100-mile mountain ultras:

~15,800 kcal to cover the distance (while consuming roughly half that)

... followed by burning 4,200-4,900 in the 24hrs *after* the race, presumably for repair and replenishment.
https://t.co/PwKDXezRDu

[Andrew Creer @AndrewCreer]

@sweatscience Thanks for the write up, it was a fun study. We are just scratching the surface on understanding wnwegy requirements for ultras…and more data is coming

[Andrew Creer @AndrewCreer]

@t_creer54 True story

[Steve Magness @stevemagness]

The athletes with the most and best functioning mitochondria in the world eat a ton of sugar…

They also train a lot…

The point? Don’t fall for this is good/evil on diet, exercise, and health.

Everything requires context.

Black and white thinking seldom works.

[Andrew Creer @AndrewCreer]

@Jared_Sumsion @BigWestSports Well played Dr. Sumsion

[Andrew Creer @AndrewCreer]

@t_creer54 Not any more…

[Andrew Creer @AndrewCreer]

@LouiseMBurke Great talk, informative AND entertaining!

[Andrew Creer @AndrewCreer]

@Jared_Sumsion @WACsports @UVUtfxc @GoUVU @UVU @uvualumni @TheDenUVU

[Michele Zanini @MicZanini]

Our new durability paper is out in SJMSS!

We tested how endurance performance determinants change after heavy-intensity running (90 and 120 min) in well-trained marathoners.

📌Below details of what we’ve found.

🆓 Open-Access
📄 https://t.co/1xWTmBF2lk

@rich_blagrove

🧵1/14

[Andrew Creer @AndrewCreer]

@UVUtfxc #uvuexercisescience

[Kristen Faulkner @FaulknerKristen]

People often ask me how much I eat when I ride. Every body is different and it depends on your goals, but here is what works for me 👇

Recovery (≤ 2 hrs): 40g/hr
Endurance (3 hrs): 60g/hr
Long Endurance (4–5 hrs): 75g/hr
Intervals: 75–80g/hr
Big days: 80–100g/hr