When there is a lot of information to cover, not even a fast-talking lecturer will be effective.
There are two reasons for this:
1. There is only so much information that learners can absorb at one time. Brain studies have found that participants can learn only 2-3 new and entirely unfamiliar items in a training segment. If the learning involves items that are familiar and meaningful to the learners, the number that participants can learn increases to 4-5 in a training segment. (Please bear in mind that a training segment is the amount of time necessary to teach the specific content to the desired level of learning. This period of time may be 5 minutes, 10 minutes, or even an hour or more.)
2. Although there are many models of learning styles, they all indicate that aural learners (those who learn by listening) comprise only a portion of total learners. The remaining learning styles (visual, interactive, print, haptic, and kinesthetic, if we use the Perceptual Learning Styles Model) do not learn in this fashion.
If the intent is merely to share information, then why not save everyone time and energy and simply mail (email or snail mail) them the information to read at their leisure?
If the intent is to ensure real learning, then reduce the amount of information. Focus on the key content and simply reference the additional nice-to-know but not essential information. Then break the lecture every five minutes or so to give the participants an interactive exercise (questionnaire, pop up, case study, discussion, simulation, demonstration, or question and answer) that engages them with the key content.