Concentric

The concentric phase of an exercise is when the muscle shortens as it generates force.
The “lifting” portion is what you are doing in most lifts. For instance, in the bicep curl, the lifting is the action. For endurance athletes, performing strength exercise which involves lifting creates power while imposing less damage on the muscles as compared to doing the lowering. The lifting portion of training also toughens joints as well as muscles. It is useful for activities like swimming, running, as well as cycling in which you repeatedly perform the same movements.