6 Signs Your Gut Is Struggling With Your Training Load (<em>#4 Is The One People Miss</em>)
When a training block starts going wrong, almost nobody suspects their digestion. You look at volume, at sleep, at whether you went too hard on Tuesday. The gut is the last thing on the list, because it isn't where you feel the problem — it's where the problem starts.
Here are six signs the limiting factor is digestive rather than programmatic. None of them is a diagnosis, and any of them can have other causes. But if you recognise three or more, the pattern is worth taking seriously.
Jump To A Sign
Food sits heavier during your heaviest weeks
It isn't what you're eating, because you haven't changed what you're eating. The same dinner that was fine in week one feels like it's still there at bedtime in week five. Digestion is competing with recovery for the same limited resources, and in a hard block it loses.
Your stomach only complains on long or hot sessions
Short and easy sessions are fine. Anything over about ninety minutes, or anything in the heat, and it becomes the limiter before your legs do. Blood is diverted away from the digestive tract toward working muscle — the longer and hotter the effort, the more pronounced that gets.
You eat well and recover badly anyway
Your nutrition is genuinely dialled in. Protein hit, carbs timed, hydration handled. And you still arrive at week five flat. What you eat and what actually crosses into circulation are two different numbers, and only one of them is on your spreadsheet.
You get ill three or four days after your biggest session
Not randomly through the winter — reliably, in the same window after peak load. If your training log and your sick days line up when you put them side by side, that isn't bad luck. That's a pattern with a timestamp.
This is the sign with the most evidence behind it. Controlled trials in adults who train have measured both sides of it: bovine colostrum reduced exercise-induced gut permeability by around 80% in one crossover study,[1] and reviews of supplementation report meaningfully fewer days with upper-respiratory symptoms.[3] Small trials, and the reviewers flagged quality limits — but the direction is consistent, and this is the one sign where the research and the pattern line up.
Your appetite vanishes exactly when you need it
The day after the hardest session, when the fuelling matters most, you can't face a proper meal. Appetite suppression after hard efforts is common, and it compounds: under-fuel the recovery day and the next block starts in a hole.
It's the same story every build, every year
The individual weeks look like separate problems. Zoom out to three seasons and it's the same shape each time — strong for a month, then something digestive, then a lost fortnight. Recurring patterns usually have structural causes.
Where Colostrum Fits
Colostrum is the first milk produced after birth, and its biological job is getting a newborn's gut barrier and defences working before it can build its own. It's naturally dense in immunoglobulins, lactoferrin and growth factors — which is why it has been studied at the gut lining rather than as a general immune supplement.
- Naturally rich in immunoglobulins (IgG) and lactoferrin
- Studied specifically in adults in regular training, which is the population these signs describe
- Supports the body's normal immune defenses through periods of heavy load
- Designed for daily use across a block — how it was studied, not as a fix once something has gone wrong
What gets claimed online
- Heals leaky gut
- Clears your skin
- Thickens hair
- Burns fat
- "Rebuilds your immune system"
What the trials actually measured
- A urinary marker of intestinal permeability
- Days with upper-respiratory symptoms
- In adults engaged in regular training
- Across small trials, several with quality limitations
We would rather show you that gap than paper over it. If you want colostrum for your skin, the controlled-trial evidence is not there.
The Pattern Is In Your Training Log
Six signs, one common thread. If yours line up with the fourth one in particular, that is the sign with the most research behind it.
See product details →Disclosure. This is an advertisement published by Modern Potion, which sells the product described above. It is not independent editorial or a news report. Nothing here is a diagnosis, and the signs listed can have many causes.
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, immunocompromised, or taking medication, or if digestive symptoms are persistent or severe.
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