Check out this month's blog post from Jenn Schwartz (Director of Injury Prevention & Fitness). Here is a link to the blog post. See below for a excerpt:
What are active stretches?
It is an advanced form of flexibility training. This form is different from static passive and dynamic stretching. Placing an outstretched leg on a chair and using the bodyweight to bring about a stretch is an example of static passive stretching. Active stretches includes a component of active muscle contraction called an isometric. An isometric contraction occurs when tension is created in the muscle group without a change in its length. These active stretches have two parts. The first is an isometric contraction and a subsequent light stretch.