Training at a fast rep speed increases the pace at which your muscles can move a given weight. (thescienceofgettingripped.com)
If you don't have time for century sets, you can still fatigue your muscle fibers with a light weight by combining different rep speeds in the same set. (muscleandperformance.com)
When lifting weights, use impeccable exercise form and controlled rep speed, in other words, do your reps without momentum. (lasting-weight-loss.com)