Variation of the exercises may be as important, if not more important, than changes in volume and intensity, and can also result in more complete muscular development.

the variations of various tensors under the Ricci flow: (31)

variation formula for the Ricci tensor (13) where is the trace, and the Lichnerowicz Laplacian (or Hodge-de Rham Laplacian) on symmetric rank (0,2) tensors is defined by the formula (14) and is the usual connection Laplacian.