I'm focusing on changing my diet this week and am so far successful--low carb, no cheats (well, it's only four days!).
Tuesday I was dead--no energy at all, occasional dizziness Tuesday and Wednesday when I changed position quickly. Those are both fairly typical for me, particularly if I cut carbs after a period of high carbs, and my carbs had indeed been high over the Christmas break! Since Tuesday, my energy has been much better and I expect it will continue. Again, I'm not shooting for ketosis: I'm still eating my lovely little clementine oranges or an apple at each meal, some nuts, green beans, salad, etc. This is more "Primal" than Atkins "Induction," and that's fine with me. I expect I'll experiment with Intermittent Fasting once I've adapted.
Sleep hasn't yet been a focus for me--good sleep some of the time, terrible on Tuesday night (just a few hours) and then last night to bed around 1:30 AM, up for a couple hours early, then back to sleep until 12:30 PM. That won't continue, if only because classes at the university where I teach begin next Tuesday and I have 8 AM classes two days a week and probably a meeting at 8 at least one other day, so it means I have to be up by 6:15 AM or so every morning. That's the time for me to work on a consistent waking time. The challenge will be getting to bed at a reasonable time (and building a night-time routine).
Exercise has also been sporadic, but OK. Walking most mornings, doing my back exercises Monday and Wednesday (I need to do a minimum of three days a week). I need to walk around campus on a regular basis as well during the day once classes start. I'm not sure when yoga will start, but probably after next week, when I've had time to adjust to my teaching schedule. It also gives me time to adapt to low carb, a little lost weight, and get my back in a bit better condition.
So, I'm happy with the way it's going so far. "Low and slow" is not only for cooking grass-fed beef!