So, could I realistically figure out my point at which fat ox is highest, but just before my body starts to turn to CHO for fuel and spend a lot of time in this “fat burning zone”? (To use a thing I’ve seen on exercise machines at the gym.
Exercise fuel utilization balance between fat and CHO is going to come from an interplay of factors, of which exercise intensity is only one. What you eat, what the ambient temperature and time of day is, stress etc all influence the fuel mix your body uses.
Unless you had OCD and controlled all these conditions down to a T, I don’t think your maximum tat oxidation rate (or what they call “fatmax”) is always going to remain pegged to one point. Its likely its going to shift around day-to-day or even just within a day.
So if you stuck to some arbitrary number and continued training at that point for prolonged duration, you risk missing out chasing your true maximum fat oxidation rate zone.
I think its far better to consult a good exercise test lab to get data/intelligence specific to your body. Ask them to elaborate on the subtle complexities surrounding fat oxidation.