With you now, the way you OP reads I seriously thought you'd been doing the same for the past 18 months with no gainsI've made a lot of progress?
I just cant get past the point I am at
.Anyway, for the very basics of diet regarding building on your gains, you want to eat above your maintanence calories each day by around 300-500 calories, at a ratio of about 20% fat, 40% carbs, 40% protein (sometimes more carbs person to person). Also, try to aim for 1.5-2g of protein per lb bodyweight.
Obviously your workout may need switching up at this point as well.
Its not a drug!

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