Due to a few, narrow studies and a myopic thought process, I have errantly marginalized and ridiculed passive stretching. Like most things, specificity of the application of any force is the key. It turns out that the tendons in the human body have different amounts of elasticity. Some tendons, like the achilles tendon, are more elastic than others. The function that they perform requires it! During portions of the gait cycle, the achilles tendon lengthens while the muscles that pull on it either shorten or maintain their length. Dickinson, et al (How Animals move: an Integrated View, Science 7 2000) define the behavior of the muscles that pull on the achilles as a strut. Furthermore, Kubo et al (Influence of static stretching on viscoelastic properties of human tendon structures in vivo, J of Applied physiology Feb 2001) found no change in maximal voluntary contraction post static stretch, however there was an increase in elasticity. So, like any other force application, we need to be specific about the mechanics and function of the portion of the contractile connective tissue continuum that we are trying to influence. And that's just the tip of this iceberg!