You can repeatedly play back one or more clips by setting markers for that frame range, such as for looping the animation of only one clip.
To repeatedly play back the animation in a clip
Right-click a clip and choose Set In/Out Loop. This sets yellow loop markers at either end of the clip.
To play back a group of clips, multi-select them, then right-click one of the clips and choose Set In/Out Loop. This sets loop markers at the beginning of the first clip and the end of the last clip, as shown below:
Click the Play button in the playback controls below the timeline to stop and start the animation.