I'm trialling doing one day keto (<20g net carbs), one day moderate (~30g) and one day higher carb (50g-60g) as I've found that eating super low carb all the time doesn't fit my body very well. I'm hoping that this will keep me in ketosis most of the time and also allow me to keep my fibre up and eat a slightly wider range of foods

Why have people suddenly started thinking that 50-60g of carbs is "higher" and keto "requires" 20g or less? Seriously, where is this coming from? *boggle*

Technically speaking, the body starts making ketones around the 100g carb intake range, and it scales up as carb intake decreases (until you reach about 2mmol/L concentration of ketones, at which point, the body becomes resistant to higher production due to the acidity of the ketones and the pH of the blood, and you start seeing diminishing returns on ketone levels). The 20g number for standard keto is really only for induction, to drain your glycogen stores quickly and get you burning more ketones sooner. It's not at all necessary to do, even at the beginning, let alone permanently, if the only reason you're doing it is for ketosis.

Also, fiber isn't actually required by the body, and in some cases, is actually counterproductive. I wouldn't sweat trying to get a certain amount of fiber simply because we're told to.

The guy that was pretty integral to increasing the fiber recommendations was Dr. Kellogg, who was the co-creator of Corn Flakes (and brother to the founder of Kellogg's), and was so obsessed with *kitten* and bowel movements that he created the cereal to inflate the amount of fiber people were consuming, so that the "plumbing" stayed insanely "clean" (because he believed the cause of sexual desire and *kitten* was solid fecal matter in the colon).

I kid you not. You can't make this stuff up.

Steady state, medium intensity cardio is counterproductive after about 30 minutes, because the cortisol release outpaces the benefits from the exercise around that length of time. High intensity intervals are better, because they promote other hormonal releases that outpace the cortisol release, and you pretty much can't do them for more than about half an hour. While we can do endurance, we're not particularly built for jogging all day, nonstop. We're built more for walking, sprinting, and lifting, and these things provide the biggest and (especially for the latter two) most efficient benefits to our health. Lifting and sprinting/HIIT spur the release of growth hormone, which helps build muscle and burn fat (while cortisol does the opposite, which is why Olympic level marathon runners very often look emaciated and amateur marathoners often complain of that extra bit of belly fat they can't seem to get rid of), it also helps balance the sex hormones (because they're all steroid hormones, which also get used/released with this kind of training), and helps regulate insulin.

I highly recommend dropping most of your cardio and picking up a barbell. I know, it can be intimidating, but most of the people in the free weight section are friendly and helpful, and/or just trying to get their own workout in. And no, you won't turn into She-Hulk.

For the rest of your cardio, make sure to vary your speed -- walk a little bit, jog a little, do full-out sprints a little. This provides the cardiovascular benefits, without the drawbacks of long-term, steady-state cardio.