@inproceedings{goffredo2005evaluation,
  title={Evaluation of Skin and Muscular Deformations in a non-rigid motion analysis},
  author={Goffredo, Michela and Carli, Marco and Conforto, Silvia and Bibbo, Daniele and Neri, Alessandro and D'Alessio, Tommaso},
  booktitle={Medical Imaging},
  pages={535--541},
  year={2005},
  organization={International Society for Optics and Photonics}
}

ABSTRACT
During contraction and stretching, muscles change shape and size, and produce a deformation of skin tissues and a
modification of the body segment shape. In human motion analysis, it is indispensable to take into account this
phenomenon and thus approximating body limbs to rigid structures appears as restrictive. The present work aims at
evaluating skin and muscular deformation, and at modeling body segment elastic behavior by analysing video sequences
that capture a sport gesture. The soft tissue modeling is accomplished by using triangular meshes that automatically
adapt to the body segment during the execution of a static muscle contraction. The adaptive triangular mesh is built on
reference points whose motion is estimated by using the technique based on Gauss Laguerre Expansion. Promising
results have been obtained by applying the proposed method to a video sequence, where an upper arm isometric
contraction was present.

ES UN ANTECEDENTE DEL ANTERIOR (carli2006study) UN POCO PEOR ME PARECE PERO PODRIAN IR CITADOS JUNTOS

The authors of \cite{goffredo2005evaluation} propose a method to analyze video sequences of static arm muscle contractions wich model the soft tissue deformation by using adaptative triangular meshes. The meshes are built over reference points whose motion is estimated. They presente an interesting paramtere to measure the alterations during the contraction called STDP witch is based on the integral area of the surface triangles.