Question: how many reps and sets for negative?
Answer: Negatives: 1-2 sets x 3 reps (5 seconds lowering phase) That is one way you can use negatives. Another way would be to add a few negative reps at the end of every set. For example, if you are performing bicep curls and the set calls for 12 reps, perform slower negatives for the last 3 reps.