There are really two interdependent components of this question: defensible training and defensible records. Great training loses much of its value if its undocumented, and meticulous records of inadequate training will seldom help your case.  For training to be legally defensible, it must be relevant to the learner’s job function or responsibilities, delivered by an instructor qualified or certified to teach that topic, and designed to improve or refresh desirable behaviors.  For records of the training to become legally defensible, they must, at a minimum, be regularly created as part of the training process, quickly entered into your files or systems, and securely maintained to prevent tampering or loss.