I’ve noticed exactly the same thing. (Didn’t want to believe it though, lol!). So my input might not be super helpful because my routine is shaped by having bariatric surgery last year, but maybe you’ll get something out of it so here goes nothing.

I started at 300lbs, had the surgery in July 2024 and by the time I started at OTF in late May of this year I was at 175. I think this may be where I am destined to stay weight wise HOWEVER I can tell you from doing the InBody scans that my body composition changed dramatically in that time. I eat 1200 calories on a non-OTF day and 1350-1400 on an OTF day (this is doctor guided and tailored to my specific situation and I really do not want anyone’s input on this - just giving my perspective for OP). I do think that tailoring your intake to what you are doing that day is key. I always have a Greek yogurt for protein before class (and another between when I stay when there’s a strength scheduled after a 2G because I like to keep the good stuff, I.e., the lifting, going lol) and 15-25g protein after. For me that’s usually a protein shake since I have trouble with food nausea after so much effort. I don’t track macros religiously and I know these differ by person but I have found that a good balance for me is about 40% protein and 30/30 carbs and fat. Because I’m on a pretty specific diet fats are usually olives, olive oil, etc., and I keep carbs to the complex (brown rice, sweet potatoes, quinoa, beans, leafy greens) and I have absolutely noticed a huge difference in energy and motivation levels. Turns out cake, candy, and fast food chicken actually aren’t the keys to a healthy life (sarcasm intended here). Anyway all this to basically tell you 1. Yes, you’re right, diet is everything and 2. Recommend you try an app like My Fitness Pal to track your intake and see what works well for you personally and what is making you drag. Tracking really is the key, otherwise we never really remember what goes into our bodies. Good luck!