I Wasn't Under-Eating. I Was Under-Absorbing.
Mile nine of an easy Sunday run, I turned around and walked home. Not because my legs were finished — because my stomach was. Third time that month, and the only run that week I'd actually been looking forward to.
I'd spent six weeks doing everything the internet tells you to do. More protein. Electrolytes in every bottle. Dinner moved earlier so there was a clean four hours before a morning session. The training was going fine on paper and I felt worse every week.
A guy I run with asked, at the trailhead, whether I'd always had "a stomach thing." I said no — it started around the time I went from four days a week to six. He said "so it started when the training did," and kept walking, and I thought about that sentence for the next three miles.
That was the part I'd had backwards. I'd been treating my stomach as a separate problem that happened to show up during a hard block. It wasn't separate. It was the block.
Here's what nobody told me, and it took a sports-medicine friend two goes to make it land. When you train hard, your body shunts blood away from your digestive tract toward the muscles doing the work. That's the correct decision in the moment. But the lining of your gut is a barrier held together by tight junctions, and under sustained load — heat and long efforts especially — that barrier gets measurably leakier.[1]
So the harder the block, the worse your absorption gets, at exactly the point your body needs the most out of what you eat. Everything I'd added was going in. The question I'd never asked was how much of it was getting across.
Why more protein, more electrolytes and an earlier dinner didn't fix it
- More protein — the constraint wasn't how much went in, it was how much crossed the barrier
- Electrolyte drinks — they replace what you sweat out; they do nothing for the barrier itself
- Moving dinner earlier — changes the timing of digestion, not what training does to the gut wall
- Probiotics — they populate the gut; that's a different job from reinforcing the lining
- Just sleeping more — real recovery, but the barrier reopens on the next hard session
Taking It In And Absorbing It Are Two Different Jobs
That one sentence explains every item on the list above. Protein, electrolytes, meal timing and probiotics all target intake. None of them target the barrier — and the barrier is the part heavy training actually stresses.
Which is where colostrum gets interesting. Colostrum is the first milk produced after birth, and its entire biological job is getting a newborn's gut barrier working. It's naturally dense in immunoglobulins (IgG), lactoferrin and growth factors — the specific compounds that job requires.
That's why it's been studied in athletes rather than just in infants. In one controlled crossover trial, gut permeability rose about two and a half times after heavy exercise on placebo; with colostrum, that rise was cut by roughly 80%.[1] A 2023 meta-analysis of ten randomised trials found a similar direction overall — though it also found the trials disagree with each other a great deal, and at least one study found the opposite.[2] Supportive, not settled. Worth knowing honestly before you buy anything.
Introducing: Colostrum Capsules
A daily capsule of bovine colostrum — the same compound family studied in those trials, aimed at the barrier rather than at intake. It isn't a replacement for eating well through a build block. It's aimed at the part of the problem that eating well doesn't reach.
- Naturally rich in immunoglobulins (IgG) and lactoferrin, the compounds studied for supporting gut barrier integrity
- Designed to support normal nutrient absorption through heavy training blocks
- Supports the body's normal immune defenses during periods of high training load
- One capsule serving, third-party tested — no mixing, no taste, nothing to rebuild your routine around
Stop Adding Input To A System That Can't Absorb It
Check Availability →Who This Is For
Your Training Is Working. Your Absorption Might Not Be.
Aimed at the barrier heavy training stresses — not at another thing to swallow and hope lands.
Check Availability →Disclosure. This is an advertisement published by Modern Potion, which sells the product described above. It is not independent editorial or a news report.
These statements have not been evaluated by the Food and Drug Administration. This product is not intended to diagnose, treat, cure, or prevent any disease. Colostrum is dairy-derived — do not take it if you have a milk allergy. Consult your healthcare provider before starting any supplement, particularly if you are pregnant, nursing, or taking medication.
[1] Marchbank et al., American Journal of Physiology — Gastrointestinal and Liver Physiology, 2011. [2] Aslam et al., Digestive Diseases and Sciences, 2023 (meta-analysis of 10 randomised trials; high heterogeneity between studies).
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