Believe in the Run debunks the keto-before-carb-load trend

The viral advice to go keto for three days before a 2.5-day carb load (loading up on carbohydrate in the days before a race) comes from 1960s research that modern work does not support, according to the Fuel for the Sole podcast from Believe in the Run. The hosts say the old theory behind it, that you deplete glycogen first so the body supercompensates when you refill, is not backed by current research.

They also list what going keto in race week can cost you. Decreased immunity, increased muscle damage, and negative mental effects during an already stressful week.

The second target is an Instagram post telling runners to skip bread during a carb load and eat only potatoes and rice. The hosts say that has no scientific basis and bread is fine.

The Berlin problem is sodium, not carbs

For a listener chasing sub-3 in Berlin, the hosts suggest 60 to 90 grams of carbs an hour, then flag the actual issue. The course has frequent water stops and Maurten drink mix, but no electrolytes. So runners have to bring their own, through salt pills, gels with sodium, or personal bottles.

The sodium options they name are Victus gels at 380 milligrams of sodium and 45 grams of carbs per gel, SiS Beta Fuel at 200mg, Never Second at 200mg, and Huma Plus. Berlin lets athletes place personal bottles at designated aid stations, and the hosts suggest decorating them so they stand out and putting them at three or four different locations.

Going past 90 grams an hour

Separately, one r/AdvancedRunning poster is 2.5 months out from a marathon and wants to move from 90 grams of carbs an hour to 120. His problem is the ratio. Most gels run 2 to 1 or 1 to 0.8 glucose to fructose, which he says pushes glucose past the roughly 60 grams an hour he can absorb, citing Steve Magness. Nobody in the thread's text named a gel that fixes it.

None of this is new science. It is a correction. The depletion phase people still post about is 60-year-old advice, and the thing most likely to wreck a Berlin race day is the sodium you did not carry.