Strength training changes what nutrition has to do. You are eating to recover from hard sets, support muscle repair, refill training fuel, and show up ready for the next session.
Enough energy comes first
A small surplus can support gaining. A deficit can support fat loss but reduces recovery resources. Maintenance can fuel performance without forcing bodyweight up or down.
Protein supports adaptation
Many lifters do well with a consistent protein target spread across meals. Meat, fish, dairy, eggs, soy, legumes, and protein powder can all work.
Carbs support output
Carbs are especially useful for high-volume lifting. If sessions feel flat, try placing carbs before and after hard workouts before blaming the program.
Hydration and sodium matter
If you sweat heavily, train in heat, or eat mostly whole foods with little salt, fluids and sodium can affect how you feel in the gym.