After someone has reached their fitness goal, how should their workout and nutrition plan be altered if they no longer wish to lose weight or build additional muscles?
please tell me about this .......
The basic rule is if you don't change your lifestyle, you won't change your physique. So if you keep your activity level the same and eat at your TDEE, you'll be in "maintenance mode". You won't gain or lose weight. You may even recomp a little, but for the most part you'll stay the same. If your activity level goes down, you'll eventually lose performance and muscle gains and you'll have to adjust your diet for the lower TDEE.
How you ultimately accomplish this is dependant on lifestyle. You can track every day or learn how to eat intuitively. Your activities become habits which you do regularly.
However, that just becomes really boring over time. I think a more sustainable solution is to pivot to another goal. People do this all the time. People who lose a lot of weight become bodybuilders. Bodybuilders become powerlifters. Runners become climbers. Afterwards your diet and training then adjust to fit the new goals.