To encourage ketone production, the amount of insulin in your bloodstream must be low. The lower your insulin, the higher your ketone production. And when you have a well-controlled, sufficiently large amount of ketones in your blood, it’s basically proof that your insulin is very low – and therefore, that you’re enjoying the maximum effect of your low-carbohydrate diet. That’s what’s called optimal ketosis.
However, due to the intense exercise, the total calorie consumption is higher. We burn more calories due to the hard muscle work – even AFTER the run. The body needs more energy for recovery, thereby burning even more calories. That’s how you benefit from post-workout fat burning and the afterburn effect (EPOC, excess post-exercise oxygen consumption).
But in today's unenlightened "believe everything you hear" age this most effective and proven approach, for some strange reason, does not seem to attract much interest. This is no more obvious when one witnesses the "technological" revolution that is happening within the fitness industry, where a newer even more ridiculous gadget compared to the one that preceded it promises to build you the body of your dreams, with little effort on your part, "in 30 days or your money back"; where a machine that does most of the work for you is touted as a suitable replacement for actually applying a modicum of effort. https://www.youtube.com/watch?v=mDHGaU_jGrQ