For runners and cyclists
Train your gut for race day.
An 8-week gut-training program for runners and cyclists. Log each long run in 30 seconds, and Racebelly tells you when your stomach is ready for more fuel.
Two comfortable sessions and you step up 10 g/hr. A rough one, and you hold.
You trained your legs for months. Did you train your stomach?
Most race-day fuelling plans fail in the gut, not the legs. Bloating, cramps and nausea kick in at 30 km, so you stop eating, and then you hit the wall.
Your gut adapts to fuel the same way your muscles adapt to training. Almost nobody trains it on purpose.
How it works
Three steps, every long session.
Get your weekly target
Racebelly picks your long and hard sessions and sets a carbs-per-hour target, translated into what to carry: two gels and a 500 ml drink mix.
Log it in 30 seconds
After your run, tap what you took and rate your gut. Time, distance and heart rate sync from Apple Health.
Level up when you're ready
Two comfortable sessions at a level and you step up. A rough one, and you hold or try a different product.
What you get
Know what your stomach can handle before the start line.
Your gut-tolerance level
Tracked week by week as it climbs toward your race target.
Products that work for you
And the ones to leave at home on race day.
Your sweat rate
In cool, mild and hot conditions, so you know how much to drink.
A race-ready profile
Take it into your race-day fuel plan, or share it with your coach.
Why I'm building this
Built by an athlete, tested on a real build-up.
I'm a runner and cyclist from Cape Town, training toward Two Oceans Ultra (56 km) and a 100 km road race in 2027. I couldn't find a simple tool that trains your gut step by step, so I'm building one and testing it on my own build-up.
The idea comes from sports science. Asker Jeukendrup's review, Training the Gut for Athletes, describes how the gut adapts to regular fuelling in training, improving comfort and carbohydrate absorption.
Questions
Is this medical advice?
No. Racebelly is a training tool based on published sports nutrition guidelines. If you have severe or persistent stomach problems, see a doctor.
Do I need specific products?
No. Use the gels, drinks and chews you already have. Racebelly tracks what works for you.
Which devices?
iPhone first, syncing with Apple Health.
When does it launch?
Waitlist members get first access, plus updates as I build it.
What will it cost?
There will be a free version. Waitlist members get founding-member pricing on the full program.