Hom dumbbell no yog cov khoom siv kev cob qhia lub zog uas feem ntau siv hauv chav ua si, nrog cov kev qhia tshwj xeeb kom tau raws li qhov xav tau ntawm cov neeg sib txawv.Qhov barbell no yog ua los ntawm cov hlau zoo. Nws yog qhov zoo rau kev cob qhia hla, nqa lub zog, nqa qhov hnyav thiab chaw ua si. Tiv thaiv kev siv zog ntau yam tsis muaj kev khoov lossis tawg.