A structured experiment in metabolic adaptation within disciplined eating windows.
Intermittent fasting often begins as a simple process that unlocks early weight regulation and mental clarity.
But over time, it becomes more complex.
Performance goals evolve.
Training intensity increases.
Fasting windows shift.
For disciplined practitioners of intermittent fasting, beginner gains pass and open up new questions:
The content I share here explores those questions through structured experimentation rather than theory.
And when coupled with a plant-based diet, not all foods work with you ahead of or after, fitness sessions or fasting windows.
Real life, real data.
I began this (ongoing) experiment in advanced intermittent fasting and plant-based performance, on 16th November 2025.
The framework includes:
Extended fasting cycles (including weekly 48-hour protocols)
Fasted strength and endurance training
Structured refeed windows and meal logging
Rather than chasing optimisation trends, the focus is on understanding cause and effect, isolating variables to improve both athletic performance and physical composition.
The goal is not simply fat loss.
It is metabolic clarity, performance resilience, and sustainable muscle definition within a structured plant-based fasting approach.
By profession, I work in UX and Conversion Rate Optimisation (CRO). Disciplines built on testing hypotheses, measuring results, and improving systems through controlled experimentation.
That same thinking is applied here.
Advanced intermittent fasting and food choices are tested alongside physical exercise sessions.
Assumptions challenged. Results tracked.
Repeated testing has revealed what improves performance, and what doesn’t.
Learn about individual challenges and questions I have tested in the blog.
The ideas explored here form the foundation of my upcoming book, Beyond 20:4 - an examination of advanced intermittent fasting, plant-based performance, and structured metabolic progression.
The book expands on the data, frameworks, and lessons emerging from this experiment.
Even experienced fasters can struggle when they begin integrating serious training into their routine. Training introduces new recovery demands such as glycogen depletion, muscle repair and electrolyte loss, which can shift when hunger signals appear.
Read blog
When the body becomes metabolically flexible through structured fasting and training, it can draw more efficiently on stored energy.
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In week 18 of my experiment, despite following the same fasting structure and eating the same types of foods, true hunger started showing up far earlier, both during the day and in the night.
Read blogBeyond 20:4 is a book documenting the discoveries and processes I have established to progress my fitness while fasting on a plant-based diet.
Register interest for updates on the manuscript development and publishing progress.
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