A current trend in computer animation research is the uses of motion capture techniques to generate libraries of basic motions. This paper presents an approach to the storage and reuse of motion capture data that integrates an adaptive filter for noise reduction with a functional representation that is highly efficient. Each motion sequence is represented as a set of non-uniform B-spline curves attached to a hierarchical model. Based on this representation a set of operations is developed that, when applied to these curves, facilitates the reuse and manipulation of pre-recorded motion. These operations include the generation of smooth transitions between motion clips, the addition of exaggerated movements to motion data, motion interpolation and motion warping.