Edit Modes and Tools : Loop Trim Tool : Trimming Looped Clips
 
Trimming Looped Clips
You can trim looped clips in two ways:
Loop Trim a looped clip to change how long the clip is looped. For example, Loop Trim a looped clip from 2 bars to four bars. With a 1 bar clip, the number of loops changes from 2 to 4. Each loop iteration remains the same length, but the length of the entire looped clip changes.
Trim the source clip (loop iteration) while keeping the overall loop length unchanged. The number of loop iterations within the looped clip changes accordingly. For example, trim a 2 bar loop iteration of a 4 bar looped clip to 1 bar. The 4 bar looped clip remains constant, but the number of loop iterations changes from 2 to 4. Each loop iteration’s length changes, but how long the clip is looped does not.