Sorry for the wait on your question .... Negatives are assisted .... You will use a weight slightly heavier than you can normally lift. this weight will be assisted quickly to the top of the movement and you will use your strength to slowly allow the bar to go to the relaxed position ... You can use these for biceps in several excercises ... My faves are straight barbell curl and at the end of my bicep program ( when I do these ) preacher curls ( curl bar ) negatives .... Do not do negatives every workout either ... just add them in once and a while... or around half the time ...check em out .... good luck