According to the Indonesian Language, Naik is already going up and Turun is already going down. So you don't use "ke atas/ke bawah" because it will be considered an Inefficient Sentence. Since you repeat the same meaning.
Actually, I am a Indonesian... and according to the rules in the language, repetitive words such as "naik ke atas" and "turun ke bawah" is incorrect. Its like a double up as Arkonide stated and is considered ineffective.
Relax guys, you can use "naik atau turun" or "ke atas atau ke bawah" or " naik ke atas atau turun ke bawah". All accepted, nothing wrong, we (Indonesian native speaker) understand all.
No need to worry...