Life Forms from Credo works with Maya and 3D Studio Max, which means that you will need to export from Life Forms into one of those packets (we would recommend 3DS Max), and then use the CAL3D exporter which is available for free at the Worldviz page under downloads:
http://www.worldviz.com/download/index.php?id=9
to export for Vizard.
this is the recommended workflow.
Here the info from the "Life Forms from Credo" homepage:
Life Forms 4.0 software is by far the most powerful character-animation package in it's price-range. Create your own animations based on default models or edit motion capture or keyframed character animations from almost any source. Includes the PowerMoves 2 CD packed with more than 750 ready-to-use motions including over 150 motion capture files.
Life Forms has advanced importing/exporting capabilities and supports the following 3D software and formats: Maya, 3D Studio Max, Lightwave, Poser, Inspire 3D, PowerAnimator, ElectricImage, Cinema 4D, BioVision BVH, Acclaim, and HTR Mocap data.