How do I stay the same body weight size?

How to I stay the same weight size? I''m not talking about In shape. I know how to stay In shape. But I was wondering how do I stay the same weight size without my weight going up and down at times.

Thank you!

Why Losing Weight Fast is Bad!

Recommended Answer:
If you are trying to lose fat then you could do weight training and cardio to gain muscle + lose fat and it should balance out.

*If you want to have the same bodyfat% then go to this site http://caloriecount.about.com/tools/calories-burned
** then eat that many calories in a day and you should be good

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