How do you pronounce 自重? Is it じじゅう or じちょう? In this context, what does it mean?

The entire clause is, その自重を支えるの翼持つ「冒険者」よ

What does this phrase mean approximately?

How do you pronounce 自重? Is it じじゅう or じちょう? In this context, what does it mean?

The entire sentence is,

その自重を支える魂の翼持つ「冒険者」よ、竜と巨人が、魔獣と亜人が住まう、幻想の世界セルデシア。

What does this phrase mean approximately?