What my training week looks like now that I'm maintaining

I’m not chasing a number anymore, just trying to keep my Tuesday soccer and Saturday long ride feeling normal. The odd part is that my hunger is so quiet on shot days that I used to under-eat before workouts and then wonder why my legs felt like sandbags. Now I keep a banana and a yogurt drink in my gym bag, and I eat something small about an hour before I leave even if I don’t feel like it. That one habit has done more for my energy than any new gadget. I still lift twice a week, mostly because it keeps my back from complaining, and I’ve accepted that my pace on the bike is a little slower than it was a year ago. For those of you who train regularly, how do you tell the difference between normal fatigue and not fueling enough?